Subscribe to RSS
DOI: 10.1055/s-0030-1250027
Potential of Cameroonian Plants and Derived Products against Microbial Infections: A Review
Dr. Victor Kuete
Department of Biochemistry
University of Dschang
P. O. Box 67
Dschang 237
Cameroon
Phone: + 23 7 77 35 59 27
Fax: + 23 72 22 60 18
Email: kuetevictor@yahoo.fr
Publication History
received February 8, 2010
revised April 29, 2010
accepted May 5, 2010
Publication Date:
08 June 2010 (online)
- Abstract
- Introduction
- Impact of Infectious Disease Worldwide and in Cameroon
- Investigation of Plants and Derived Products as Sources of New Antimicrobial Agents
- Biological Activity Screening of Plant Extracts for Antimicrobial Effects in Cameroon
- Antimicrobial Compounds from Cameroonian Medicinal Plants
- Conclusions
- Acknowledgements
- References
Abstract
In Cameroon, infectious diseases are amongst the most commonly notified diseases and largest cause of mortality. Many plants are used locally in traditional medicine for their treatment. The aim of the present review is to summarize currently available evidence and knowledge concerning Cameroonian plants used to treat bacterial and fungal infections, and the efficacy of plant-derived extracts and compounds. The traditional uses of plants in the treatment of infectious diseases have been collected and tabulated. The antimicrobial activity of the extracts and the chemical constituents of most of these plants are summarized in this report. Plants used traditionally in Cameroonian medicine, with laboratory work on any part or products, have been documented. Numerous extracts and compounds have been tested for antimycobacterial, antibacterial and antifungal efficacy and some of them were significantly active. Most of the bioactive compounds isolated were phenolics and alkaloids. In conclusion, many plant species are used in traditional medicine in Cameroon to treat infectious diseases, and several interesting openings have originated for further inquiry following in vitro antimicrobial activity evaluation. However, much work is still to be done to standardize methods and cut-off points for describing the antimicrobial activity, and on the study of the mechanisms of action.
Key words
infectious diseases - bacteria - fungi - medicinal plants - bioactive compounds - Cameroon
Introduction
The importance of medicinal plants as a source of new antimicrobials is well established today. Approximately 25 % of the active substance prescriptions in the United States come from plant material [1]. It is estimated that as many as 20 000 species from several families are useful for these purposes [2]. In the two last decades, the search for antimicrobial potential of medicinal plants in Cameroon has experienced a tremendous growth. Significant numbers of scientific publications have been produced and many research teams have addressed this area. When searchingfor publications relative to the antimicrobial activity of Cameroonian medicinal plants or compounds from natural sources, it was found that the first works were published in 1988 by Biyiti et al. [3]. Evidence of the efficiency of herbal drugs used in Cameroonian medicine in the treatment of microbial infections is being provided continuously and intensively today [4], [5], [6]. More than a hundred studies were published from 1987 to 2009, according to scientific websites such as Pubmed, Sciencedirect, Scirus and Scopus. This paper summarizes the currently available knowledge on Cameroonian plants used to treat microbial diseases, and the efficacy of plant-derived extracts and compounds. Numerous medicinal plants are commonly used in both urban and rural areas in Cameroon as well as in most African countries, in the treatment of infectious diseases. The WHO [7] estimated that 80 % of the African population is concerned and believes that this practice, if applied appropriately, could significantly contribute to improve public health. In the plant kingdom, medicinal plants from several families are used for therapeutic purposes. This review will be focused on the plant families Moraceae, Irvingiaceae, Melianthaceae, Rutaceae, Guttiferae, Bignogniaceae, Ebenaceae, etc., reported for their antimicrobial activities. Several classes of secondary metabolites have been characterized as the active principles of the plants, including terpenoids, alkaloids and phenolic compounds such as chalcones, flavones, isoflavones, anthraquinones, naphthoquinones, xanthones, and coumarins. Later in this report, we will discuss the use of the studied plants in traditional therapy, the antimicrobial activity of extracts of the plants studied in each family, and finally the plant-derived metabolites characterized to date in Cameroon.
#Impact of Infectious Disease Worldwide and in Cameroon
With the advent of globalization, health threats have become much more serious in an increasingly interconnected world, characterized by higher mobility of people, animals and goods, economic interdependence and electronic connectivity [8]. According to the WHO, at least 39 new pathogens have been identified since 1967, including HIV, Ebola and Marburg hemorrhagic fevers [9]. In addition, “centuries-old threats” like influenza, malaria and tuberculosis continue to thrive due to a combination of biological mutations, rising resistance to antibiotics and weak health systems [9]. In the last five years, the WHO has verified more than 1100 epidemic events worldwide [8]. Infectious diseases cause about 70 % of deaths in children in developing countries and more than a third of those deaths occur in neonates [8]. More than 80 % of tuberculosis cases occur in Asia and Africa [10]. In Cameroon, the major infectious diseases associated with a high degree of risk within the population include food or waterborne diseases (bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever), vector borne diseases (malaria and yellow fever), water contact disease (schistosomiasis), respiratory disease (meningococcal meningitis), and animal contact disease (rabies) [11]. Very often, there is a coexistence of many infectious diseases. Ammah et al. [12] demonstrated that a high proportion of patients (33 %) had malaria coexisting with S. typhimurium, S. paratyphi, and S. typhi infections. In our population, the lifetime risk of developing active tuberculosis once infected, in the absence of HIV infection, is about 10 %, meanwhile this risk increases tenfold in HIV-infected individuals [13]. The unsatisfactory case management of the whole infectious diseases in general, and particularly bacterial and fungal infections throughout the continent, which allows partially treated and relapsed patients to become sequentially resistant, may play a significant role in the development of resistance [14], [15]. Effective treatment of microbial infections is challenging for various reasons including lack of accessibility and elevated expense of drugs and low adherence owing to toxicity of second-line drugs [14], [15]. It is all too likely that the emergence of even more resistant microbial strains will be experienced in the future, exhausting the current arsenal of chemical defenses at our disposal [14]. For this purpose, new antimicrobial agents are urgently needed, and research programs into alternative therapeutics should be encouraged. It has been suggested that the best available in vitro indicator of possible therapeutic activity is the early microbicidal activity of medicinal plants [7], drugs or combinations of drugs [16].
#Investigation of Plants and Derived Products as Sources of New Antimicrobial Agents
Plants produce a great diversity of substances that could be active in many fields of medicine. Natural products from plants are proven templates for new drug development [17], and have shown many interesting biological activities. In a review of medicinal plants as antimicrobial agents [18], it was estimated that at least 12 000 active compounds have been isolated from plants, representing less than 10 % of the total. Several recent reviews have highlighted the underutilized potential of plant species and natural products as sources of antimicrobial drugs [14]. Plant-derived antimicrobial compounds belong to an exceptionally wide diversity of classes, such as alkaloids, terpenoids, peptides and phenolics [18]. Numerous assay systems and organisms have been used to screen plant extracts and constituents of active plants for antimicrobial activity. The microbroth dilution method seems to be more appropriate when investigating the activity of compounds. However, this method has several advantages compared to another method used in the past; the agar diffusion method. The microbroth dilution method is quantitative, allows the use of small quantities of compounds or plant extracts as well as culture media, and is well adapted for drugs intended for systemic use [19]. Colorimetric microbroth techniques using various reagents such as tetrazolium salts [20], [21], or color indicators [22] allow easy MIC detection and increase the credibility of this method. For the antimycobacterial tests of plant-derived substances, a number of bioassay systems has been used including agar diffusion and dilution assays, radiorespirometry (using the BACTEC 460 instrument), and broth macro- and micro-dilution assays to reporter gene assays [14].
#Biological Activity Screening of Plant Extracts for Antimicrobial Effects in Cameroon
Plants extracts are widely used in many parts of Cameroon to treat infectious diseases or related symptoms including abdominal pains, itching, urinary and respiratory ailments, fever and coughing, diarrhea. Adjanohoun et al. [23] provided a useful review of the traditional use of medicinal plants in Cameroon, although much work remains to be done regarding the documentation of existing ethnobotanical knowledge. Cameroon possesses a very rich and diverse flora, with an estimated 8260 species [24]. This paper is the first review on Cameroonian medicinal plants and derived products as a source of antimicrobial agents. It is important to note that a minimal inhibitory concentration (MIC) value of 100 µg/mL was used as a criterion for antimicrobial activity classification in accordance with some authors who consider a MIC value between 100–200 µg/mL as positive for plant extracts [25], [26], [27], [28], [29]. The plants with scientific reports on their activities of any part or derived products against microorganisms ([Table 1]) are summarized in [Table 2]. In this review, the activity of plant extracts or compounds will also be discussed, but not classified if the documented results were based only on the inhibition zone determinations. However, in this paper, the activity of plant extracts will be classified as significant (MIC < 100 µg/mL), moderate (100 < MIC ≤ 625 µg/mL) or weak (MIC > 625 µg/mL).
Microorganisms |
Abbreviation |
Microorganisms |
Abbreviation |
Microorganisms |
Abbreviation |
Aspergillus niger |
A. niger |
Cladosporium sp. |
– |
Salmonella typhi |
S. typhi |
Aspergillus flavus |
A. flavus |
Enterococcus hirae |
E. hirae |
Pseudomonas aeruginosa |
P. aeruginosa |
Alternaria sp. |
– |
Escherichia coli |
E. coli |
Scenedesmus subspicatus |
S. subspicatus |
Bacillus subtilis |
B. subtilis |
Fusarium sp. |
– |
Shigella dysenteriae |
S. dysenteriae |
Bacillus stearothermophilus |
B. stearothermophilus |
Geotrichum candidum |
G. candidum |
Shigella flexneri |
S. flexneri |
Bacillus cereus |
B. cereus |
Klebsiella pneumoniae |
K. pneumoniae |
Staphylococcus aureus |
S. aureus |
Bacillus megaterium |
B. megaterium |
Microsporum audouinii |
M. audouinii |
Staphylococcus saprophyticus |
S. saprophyticus |
Aspergillus ochraceus |
A. ochraceus |
Citrobacter freundii |
C. freundii |
Streptococcus anginosus |
S. anginosus |
Enterobacter cloacae |
E. cloacae |
Cryptococcus neoformans |
C. neoformans |
Streptococcus faecalis |
S. faecalis |
Enterobacter aerogenes |
E. aerogenes |
Morganella morganii |
M. morganii |
Streptococcus mutans |
S. mutans |
Candida glabrata |
C. glabrata |
Mucor miehei |
M. miehei |
Streptococcus oralis |
S. oralis |
Corynebacterium glutamicum |
C. glutamicum |
Mycobacterium smegmatis |
M. smegmatis |
Streptococcus pneumoniae |
S. pneumoniae |
Candida albicans |
C. albicans |
Mycobacterium tuberculosis |
M. tuberculosis |
Streptococcus pneumoniae |
S. pneumoniae |
Haemophilus influenza |
H. influenza |
Neisseria gonorrhoeae |
N. gonorrhoeae |
Streptococcus pyogenes |
S. pyogenes |
Chlorella sorokiniana |
C. sorokiniana |
Penicillium sp. |
– |
Streptomyces viridochromogenes |
S. viridochromogenes |
Candida krusei |
C. krusei |
Penicillium verrucosum |
P. verrucosum |
Trichophyton mentagophytes |
T. mentagophytes |
Candida tropicalis |
C. tropicalis |
Proteus mirabilis |
P. mirabilis |
Trichophyton rubrum |
T. rubrum |
Chlorella vulgaris |
C. vulgaris |
Proteus vulgaris |
P. vulgaris |
Vibrio anguillarium |
V. anguillarium |
(−) Only provided when the species is determined |
Family |
Speciesa |
Traditional treatment |
Plant part used |
Bioactive (or potentially active) compounds |
Screened activityb for crude plant extract |
Annonaceae |
Monodora myristica |
headache, constipation, sores, guinea worm infections [77] |
seeds |
not identified but the active essential oil from fruits contained α-phellandrene; p-cymene; α-pinene; cis-sabinol; limonene [77] |
(fruits essential oils) Q: Af, Bc, Bs,Cgl, Ec, Kp, Sa, Sf [77] |
Xylopia aethiopica |
cough, bronchitis, dysentery, female sterility [77] |
seeds |
not identified but the active essential oil from fruits contained β-pinene; terpinen-4-ol; sabinene; α-phellandrene; α-terpineol; α- and trans-β-ocimene [77] |
(fruits essential oils) S: Af, Bc, Ec, Sa, Sf; Q: Cgl [77] |
|
Apocynaceae |
Tabernaemontana crassa Benth. (43449/HNC) |
gonorrhea fungal infections, ovarian trouble, anthrax, headache, constipation, disinfections, homeostasis [78] |
leaves, stem bark, sap |
dehydrocorydalmine; palmatine; isoursenol; acetate of isoursenol; lupeol [76] |
(bark methanol extract) W: Ca, Ck, Ec, Kp, Ng, Pa, Pv, Sa, Sd, Sf, Sp, St [76] |
Asteraceae |
Emilia coccinea (Sims) G. Don (6297/Leeuwenberg) |
diarrhea, stomachache, bowel, bladder disorders, wounds disinfection [79] |
leaves |
not identified but preliminary phytochemical study of active methanol leaf extract revealed the presence of alkaloids, flavonoids, tannins, saponins and cardiac glycosides [80] |
(leaves methanol extract) W: Ec, Sa, St [80] |
Crepis cameroonica Babc. |
diarrhea, wounds and fungal infections [81] |
not specified |
3β,9β-dihydroxyguaian-4(15),10(14),11(13)-trien-6,12-olide; 8α-hydroxy-4α(13),11β(15)-tetrahydrozaluzanin C; 8-desacylcynaropicrin [81] |
(aerial part methanol extract) Q: Ec, Sa [81] |
|
Bignogniaceae |
Newbouldia laevis Seem. (1754/SRFK) |
diarrhea, dysentery, worms, malaria, sexually transmitted diseases, dental caries [83] |
leaves, stem bark, roots |
newbouldiaquinone A [82]; chrysoeriol; newbouldiaquinone; 2-acetylfuro-1,4-naphthoquinone; 2-hydroxy-3-methoxy-9,10-dioxo-9,10-dihydroanthracene-1-carbaldehyde; lapachol; β-sitosterol-3-O-β-dglucopyranoside; oleanolic acid; canthic acid; newbouldiamide; 2-(4-hydroxyphenyl)-ethyl trioctanoate [48] |
(bark methanol extract) S: Bc, Bm, Bs, Bst; M: Ca, Ck, Cg, Ea, Ec Ecl, Cf, Mm, Kp, Pa, Pm, Pv, Sd, Sfl, Sf, St; W: S a [48] |
Stereospermum zenkeri K. Schum. ex De Wild (1022/SRFK) |
bronchitis, microbial infections [84] |
leaves, stem bark |
zenkequinone A and B, sterequinone-F, p-coumaric acid [84] |
crude extract was not investigated but zenkequinone B presented a MIC value of 9.50 µg/mL on P. aeruginosa [84] |
|
Caesalpiniaceae |
Erythrophleum suaveolens (Guill. & Perr.) Brenan, (2644/SRFK) |
inflammation, analgesic, bacterial and fungal infections, chickenpox, gangrenous sores, cardiovascular diseases [85] |
stem bark |
norcassaïde; norerythrosuaveolide [75] |
crude extract was not investigated but active diterpenoid alkaloids were isolated from the stem bark [75] |
Ebenaceae |
Diospyros crassiflora (4924/SRFK) |
gonorrhea and other bacterial and fungal infections, tuberculosis [49], [86], [87], [88] |
stem bark |
(bark dichloromethane : methanol 1 : 1 extract) W: An, Af, Asp, Ca, Cg, Ck, Ct, Csp, Cn, Fsp, Gc, Psp [88] |
|
(Bark methanol extract) S: Ms, Mtb, Ng [49] |
|||||
Diospyros canaliculata (9653/SRF/cam) |
gonorrhea and other bacterial and fungal infections, tuberculosis [49], [86] |
stem bark |
S: Ms, Mtb, Ng [49] |
||
Euphorbiaceae |
Bridelia grandis Pierre ex Hutch (BWPV01) |
rheumatism, arthritis, abdominal pain, thrush, oral cavity affection [89], [90] |
stem bark, leaves, roots, fruits |
not identified but qualitative phytochemical analyses and colorimetric assays, together with preliminary chromatographic separations of the most active bark extracts, clearly suggested the presence of condensed tannins as main constituents of the phytocomplex responsible for the biological activity [90] |
(bark water extract) M: Sm, San, So, Sp [90] |
Bridelia ferruginea |
dysentery, diabetes, thrush mycotic stomatitis in children, antidote for snakebite, gonorrhea, poisons [91] |
stem bark, leaves, fruits |
not identified but qualitative phytochemical analyses of the plant revealed the presence of triterpenes, steroids, tannins, saponins, flavonoids [92] |
(leave methanol extract) W: Bs, Ec, Sa, Sf [92] |
|
Mallotus oppositifolium |
diarrhea and dysentery [93] |
leaves |
not yet identified |
(leave methanol extract) W: Sd [93] |
|
Fabaceae |
Eriosema glomerata 643/HNC |
infectious diseases [94] |
whole plant |
erioschalcones A, erioschalcones B, quercetin, isoluteolin [94] |
Crude extract was not investigated but active compounds were isolated from CH2Cl2-MeOH extract of the whole plant [94] |
Guttiferae |
Mammea Africana 4221/SRF/CAM |
stomach pains, scabies, skin diseases, rheumatic pain, cough [95] |
stem bark, fruit |
mammea A/AA, mammea C/OB [95] |
crude extract was not tested but active coumarins were isolated from the stem bark [95] |
Allablackia gabonensis (Pellegr.) Bamps (23255/HNC) |
dysenteries, cold, tooth aches [56] |
stem bark |
allanxanthone A; allanxanthone D; 1,3,6,7-tetrahydroxy-2-(3-methylbut-2-enyl)xanthone [56] |
crude extract was not investigated but active xanthones were isolated from the stem bark [56] |
|
Calophyllum inophyllum L. (32189/SRF/Cam) |
cicatrisant,analgesic, wounds and herpes infections [74] |
stem bark, roots, fruits |
caloxanthone A, calophynic acid, brasiliensic acid, inophylloidic acid, calaustralin, calophyllolide, inophyllum C, inophyllum E [96] |
[(root bark and fruits CH2Cl2-MeOH (1 : 1) extract] Q: Sa [96] |
|
Garcinia kola Heckel |
infectious diseases, respiratory tract infections [97] |
fruits |
not yet identified |
(fruits ethanol extract) S: Sa, Sp, Spn, Hi [97] |
|
Garcinia smeathmanii oliver (35 169/HNC) |
bacterial and fungal infections [51] |
stem bark |
cheffouxanthone; 1,5 dihydroxyxanthone; 1,3,5-trihydroxyxanthone; bangangxanthone A; smeathxanthone B; smeathxanthone A; guttiferone I; isoxanthochymol; friedelin; triacontanyl caffeate [51] |
(bark methanol extract) S: Bm, Bs, Ea, Ec, Kp, Mm, Pa, Pv, Sf, St; M: Bc, Bst, Ca, Cg, Ck, Cf, Ecl, Pm, Sd [51] |
|
Garcinia staudtii Engl (167341/HNC) |
bacterial infections, cancer [98] |
stem bark |
staudtiixanthone A; staudtiixanthone B (2); α-mangostin; gartanin; staudtiixanthones C; staudtiixanthones D; demethylcalabaxanthone garcinone B [98] |
crude extract was not investigated but isolated compounds were active on S. aureus [98] |
|
Symphonia globulifera Linn f. (syn. S. gabonensis Pierre) (2235/SRFK) |
laxative for pregnant women, fatigue, bacterial infections [56], [99], [100] |
stem bark, fruits |
globuliferin [100]; globulixanthone C; globulixanthone D; globulixanthone E [56] |
(seeds methanol extract) W: Ec, Sa, Sf, Kp [100] |
|
(roots bark CH2Cl2-MeOH extract) S: Bs, Sa, Va [56] |
|||||
Vismia guineensis (Linn.) Choisy. (75 346/HNC) |
leaves, stem bark, roots |
3-geranyloxy-6-methyl-1,8-dihydroxyanthraquinone; vismiaquinone; vismiaquinone B; betulinic acid (roots) [53]; vismiaquinone; caloxanthone J; O1-demethyl-3′,4′-deoxypsorospermin-3′,4′-diol; 6-deoxyisojacareubin; 1,7-dihydroxyxanthone (barks) [53]; friedelin; 1,8-dihydroxy-6-methoxy-3-methylanthraquinone; kaempferol (leaves) [53] |
(leaves methanol extract) S: Ca, Cf, Ecl, Mm, Sfl, Tm, Tr; M: Bs, Bst, Cg, Ea, Ec, Kp, Ms, Pm, Pv, Sa, Sd, St |
||
(bark methanol extract) S: Ca, Bst, Ecl, Mm, Sfl,Tm, Tr; M: Bs, Ca, Cf, Cg, Ea, Ec, Kp, Ms, Pm, Pv, Sa, Sd, St |
|||||
(roots methanol extract) S: Ca, Bst, Ecl, Mm Ms, Mtb, Sfl, Tm, Tr; M: Bs, Ca, Cf, Cg, Ea, Ec, Kp, Ms, Pm, Pv, Sa, Sd, St [53] |
|||||
Vismia rubescens Oliver 43288/HNC |
skin diseases, diarrhea and venereal diseases [102] |
stem bark, roots |
1,4,8-trihydroxyxanthone; 1,7-dihydroxyxanthone; physcion; friedelin; friedelanol [102] |
(bark methanol extract) M: Sa, St; W: Pa, Ca [102] |
|
Irvingiaceae |
Irvingia gabonensis (Aubry Lecomte ex O'Rorke) Baill. (28054/HNC) |
gonorrhea, gastrointestinal and hepatic disorders, wound infections, diabetes, analgesic [103], [104], [105], [106], [107] |
leaves, stem bark, roots, fruits |
3-friedelanone; betulinic acid; oleanolic acid; 3,3,4-tri-O-methylellagic acid; 3,4-di-O-methylellagic acid; hardwickiic acid [39] |
(bark methanol extract) S: Bst, Ca, Cf, Ea, Ecl, Mm, Ng, Pa, Pm, Pv, Sa, Sd; M: Bc, Bm, Bs, Ck, Ec, Kp, Sfl, St, Sf [39] |
Lamiaceae |
Ocimum gratissimum |
pulmonary antiseptic, antitussive, antispasmodic [108] |
leaves |
not identified but essential oils from fruits contained thymol; γ-terpinene; p-cymene; limonene; α-terpinolene; α-phellandrene; 1,8-cineole; α-terpineol; β-caryophyllene; dehydro-p-cymene; 3,9-epoxy-p-mentha-1,8-diene [108] |
(essential oil) Q: Bc, Bs,Cgl, Ec, Sa, Sf [102] |
Thymus vulagris L. 42851/HNC |
fungal infections [109] |
whole plant |
essential oil, with nonidentified components [109] |
(essential oil) Q: Ao [109] |
|
Lauraceae |
Beilschmiedia anacardioides (Engl. & K. Krause) Robyns & Wilczek |
uterine tumors, Rubella, female genital infections, rheumatism [110] |
stem bark |
beilschmiedic acid A, B and C [110] |
crude extract was not investigated but active endiandric acid derivatives were isolated from the stem bark [110] |
Moraceae |
Dorstenia angusticornis Engl. (28165/SRFCam) |
gastroenteritis, diarrheal infections [42] |
whole plant |
gancaonin Q; stipulin; angusticornin B; bartericin A [42] |
(twigs methanol extract) S: Bc, Bm, Ca, Ck, Ea, Ng, Pm, Pv, Sa, Sd, Sf, Sfl; M: Bs, Bst, Cg, Cf, Ec, Ecl, Ec, Kp, Mm, Pa, St [42] |
Dorstenia barteri Bureau (44016/HNC) |
snakebite, rheumatic, infectious diseases, arthritis [111], [112], [113] |
whole plant |
isobavachalcone; stipulin; 4-hydroxylonchocarpin; kanzonol C; amentoflavone [5] |
(twigs methanol extract) S: Bc, Bm, Bs, Bst, Ca, Cg, Cf, Ck, Ea, Ec, Ecl, Kp, Ma, Mm, Pa, Pm, Pv, Sa, Sd, Sf, Sfl; M: St, Tr [5] |
|
Dorstenia elliptica Bureau (44018/HNC) |
eye infections [114] |
whole plant |
psoralen; O-[3-(2,2-dimethyl-3-oxo-2H-furan-5-yl)butyl]bergaptol or dorstenin; bergapten; O-[3-(2,2-dimethyl-3-oxo-2H-furan-5-yl)-3-hydroxybutyl]bergaptol; 3-(3,3-dimethylallyl)-4,2′,4′-trihydroxychalcone [43] |
(twigs methanol extract) S: Bm, Bst, Ca, Cf, Ea, Ec, Ecl, Pm, Pv, Sf, Sfl; M: Bc, Bs, Cg, Kp, Ma, Pa, Pv, Sa, St, Tr [43] |
|
Dorstenia turbinata Engl. (28158/SRF/Cam) |
gastroenteritis, skin infections, gastroenteritis, skin infections, rheumatism [6] |
whole plant |
5-methoxy-3-[3-(β-glucopyranosyloxy)-2-hydroxy-3-methylbutyl]psoralen; 5-methoxy-3-(3-methyl-2,3-dihydroxybutyl)psoralen; (2′S,3′R)-3′-hydroxymarmesin; 4-hydroxy-3-ethoxybenzaldehyde; 4-methoxyphenol, psoralen; kanzonol C; 4-hydroxylonchocarpin; umbelliferone [6] |
(twigs methanol extract) S: Ca, Cf, Cg, Ec, Kp, Ma, Pa, Sa, Sd, St, Tr [6] |
|
Ficus chamydocarpa Mildbraed & Burret. (35446/HNC) |
filaris, diarrheal infections and tuberculosis [44] |
stem bark |
β-amyrin; alpinumisoflavone; genistein; laburnetin; luteolin [44] |
(bark methanol extract) M: Bc, Bst, Ca, Cg, Ecl, Mm, M, Pm, Sa [44] |
|
Ficus cordata Thunb. 35446/HNC) |
filaris, diarrheal infections and tuberculosis [44] |
stem bark |
β-amyrin; β-sitosterol-3-O-β-d-glucopyranoside; catechin; epiafzelechin [44] |
(bark methanol extract) S: Ca, Cg, Ms, Mtb,Cf, Ec, Ecl, Kp, Mm, Pm, Sd, St; M: Pa [44] |
|
Ficus ovata Vahl., 26996SRF/Cam |
infectious diseases, gastrointestinal infections, diarrhea, anti-poison [109] |
leaves, stem bark |
3-friedelanone; taraxeryl acetate; betulinic acid; oleanoïc acid; 2′-hydroxyisoprunetin; 6,7-(2-isopropenyl furo)-5,2′,4′-trihydroxyisoflavone; Cajanin; protocatechuic acid [115] |
(Bark methanol extract) M: Bc, Ca, Cf, Ec, Kp, Pa, Sa, Sd, St [115] |
|
Morus mesozygia Stapf. (4228/SRFK) |
arthritis, rheumatism, malnutrition, debility; pain-killers, stomach disorders, wound infections, gastroenteritis, peptic ulcer, infectious diseases [78], [116] |
stem bark |
marsformoxide B; moracin Q; moracin T; artocarpesin; cycloartocarpesin; moracin R; moracin S; moracin U; moracin C; moracin M [45] |
(bark methanol extract) S: Bc, Ca, Ec; M: Kp, Pa, Sa, Sd, Sf, St [45] |
|
Treculia acuminata Baillon (2921/SRF/Cam) |
treat skin diseases, dental allergy, amoebic dysentery and AIDS [117], [118] |
leaves, stem bark, roots |
catechin; 6,9-dihydroxymegastigmane-3-one; 2,3-dihydroxypropylhexadecanoate [62] |
(twigs methanol extract) S: Bm, Ea, Ecl, St; M: Ca, Cg, Ck, Ec, Pa, Pm, Pv, Bs [62] |
|
Treculia africana Decaisne (29053/SRF/Cam) |
treat skin diseases, dental allergy, amoebic dysentery and AIDS [117], [118] |
leaves, stem bark, roots |
phyllocoumarin; catechin; 6,9-dihydroxymegastigmane-3-one [62] |
(leaves methanol extract) S: Bs, Ca, Cf, Ck, Ea, Ec, Kp, Mm, Pm, Pv, Sd, Sf; M: Bst, Cg, Ea, Pa, Sa, St [62] |
|
Treculia obovoidea N. E. Brown (44055/HNC) |
treat skin diseases, dental allergy, amoebic dysentery and AIDS [117], [118] |
leaves, stem bark, roots |
psoralen; bergapten; 7-methoxycoumarin; 7-hydroxycoumarin; 4,2′,4′-trihydroxychalcone; 4,2′,4′-trihydroxy-3-prenylchalcone; 3-hydroxy-4-methoxybenzoic acid; O-[3-(2,2-dimethyl-3-oxo-2H-furan-5-yl) butyl]bergaptol [22] |
(twigs methanol extract) S: Bc, Bs, Ca, Cf, Ck, Pv; M: Bm, Bst, Cg, Ec, Ecl, Kp, Pa, Sf, Sa, Sfl, St [22] |
|
Hypericaceae |
Harungana madagascariensisc Lam. ex. Poir (HNC 32358) |
– |
leaves |
harunmadagascarin D, 1,7-dihydroxyxanthone [119] |
crude extract not investigated but harunmadagascarin D isolated from leaves was active on B. cereus [119] |
Meliaceae |
Turreanthus manii (Baill.) (18312/SRF/Cam) |
infectious diseases [120] |
stem bark |
16-acetoxy-12,15-epoxy-15β-hydroxylabda-8(17),13-diene [120] |
(stem bark methanol extract) Q: Bs, Ec, Mmi, Cv, Ss [120] |
Melianthaceae |
Bersama engleriana Gurke (24725/HNC) |
cancer, spasms, infectious diseases, male infertility, diabetes [121] |
leaves, stem bark, roots |
not identified but flavonoids, phenols, triterpenes, saponins and anthraquinones were detected in all parts of the plant [122] |
(leaves methanol extract) S: Bst, Ms, Kp, Mm, Pa, St; M: Bc, Bs, Ca, Cf, Cg, Ec, Ecl, Sd, Sf, Sa, Sfl [122] |
(bark methanol extract) S: Bs, Bst, Ca, Cf, Cg, Ec, Ecl, Kp, Mm, Ms, Mtb, Pa, Sd, Sf, Sa, Sfl, St [122] |
|||||
(roots methanol extract) S: Bs, Bst, Ca, Cf, Cg, Ec, Ecl, Kp, Mm, Ms, Mtb, Pa, Sd, Sf, Sa, Sfl, St [122] |
|||||
Ochnaceae |
Campylospermum glaucumc (Tiegh) Farron (28192/SRF/Cam) |
– |
stem bark |
not identified |
(bark methanol extract) W: Eh, Sa, Ssp [123] |
Ouratea sulcata Van Tiegh (ex Keay) (10133/SRF/Cam) |
upper respiratory tract infections, dysentery, diarrhea, toothache [114] |
leaves |
sulcatone A, 3-hydroxy-2,3-dihydroapigenyl-[I-4′,O,II‐3′]-dihydrokaempferol, amentoflavone [124] |
(leaves methanol extract) W: Bs, Sa, Va [124] |
|
(leaves CH2Cl2-MeOH extract) M: Bs, Sa, Va [124] |
|||||
Ouratea turnarea (Hook) Hutch & Dalzc (10134/SRF/Cam) |
– |
stem bark |
not identified |
(bark methanol extract) W: Eh, Sa, Ssp [123] |
|
Poaceae/Gramineae |
Cymbopogon citratus(DC) Stapf. (18628/SRF/Cam) |
fungal infections [109] |
leaves |
essential oil, with non-identified components [109] |
(essential oil) Q: Ao [109] |
Rhamnaceae |
Maesopsis eminii (Engler) (234/SRF/Cam) |
diuretic, purgative, emetic, and antidiarrhetic, abortifacient [125], [126] |
stem bark |
1α,3 β -dihydroxybauer-7-en-28-oic acid [125] |
crude extract was not investigated; a diterpenoid 1α,3β-dihydroxybauer-7-en-28-oic acid isolated from the stem bark was active on B. cereus [125] |
Rutaceae |
Tecla afzelii Engl. (10674/SRF/Cam) |
wound infections, abdominal pains, cough, fever, asthma [127] |
stem bark |
kokusaginine; maculine; kolbisine; lupeol [41] |
(bark methanol extract) S: Bs, Ca, Cg, Ec, Ma, St; M: Ms [41] |
Oriciopsis glaberrima Engl. (1888/HNC) |
infections, hypotension, mycoses, dermatitis [114] |
Stem bark |
oriciacridone A and B, lichexanthone [128] |
(bark CH2Cl2-MeOH extract) Q: Bs, Ca, Cv, Cs, Mmi, Sa, Ss, Sv [128] |
|
Zanthoxylum leprieurii |
gonorrhea, kidney pain, sterility [77] |
not specified |
Not identified but essential oils from fruits contained trans-α-ocimene; α-terpinolene; 3-δ-carene; limonene; myrcene; α-pinene; p-cymene [77] |
(fruits essential oils) S: Sa [77] |
|
Zanthaxylum xanthoxyloides |
enteritis, dysentery, diarrhea, guinea worm, uretritis and as an anti-odontalgic [77] |
not specified |
not identified but essential oils from fruits contained α-pinene; trans-β-ocimene; citronellol; sabinene; myrcene; limonene; cytronellyl acetate; α-phellandrene [77] |
(fruits essential oils) S: Ec, Bc, Bs, Af, Kp, Sa, Sf [77] |
|
Sapotaceae |
Tridesmostemon omphalocarpoides Engl. (3829/HNC) |
gastroenteritis, skin lesions [129] |
stem bark |
not identified but preliminary phytochemical studies reported the presence of alkaloids, phenols, polyphenols, saponins, tannins, triterpenes, anthraquinones and steroids in bark methanolic extract and their variation in active fractions [129] |
(bark methanol extract) S: Ec; M: Ca, Ck, Sd, Kp, Sa, Sf [129] |
Solanaceae |
Slonanum tovum Sw. (49 427/HNC) |
bacterial and fungal infections, HIV, herpes simplex virus type I and II infections [76], [130], [131], [132] |
leaves, stem bark, fruits |
steroidiques glycosides, chlorogenone, neochlorogenone [131], [132], solasodine, lupeol [76] |
(fruits ethanol 70 % extract) M: Ca, Ck, Ec, Ng, Pa, Pv, Sd, Sfl, Sa, St, Sf [76] |
Zingiberaceae |
Zingiber officinale |
infectious diseases, respiratory tract infections [98] |
roots |
not yet identified |
(roots ethanol extract) S: Sa, Sp, Spn, Hi [98] |
a HNC or SRFK: Cameroon national herbarium code; b Screened activity: significant, S: MIC < 100 µg/mL), moderate (MIC: 100 < MIC ≤ 625 µg/mL), weak (W: MIC > 625 µg/mL), Q: qualitative activity based on inhibition zone determination; An: Aspergillus niger; Af: Aspergillus flavus; Asp: Alternaria sp.; Ao: Aspergillus ochraceus; Bc: Bacillus cereus; Bm : Bacillus megaterium; Bs: Bacillus subtilis; Bst: Bacillus stearothermophilus; Ca: Candida albicans; Cn: Cryptococcus neoformans; Cf: Citrobacter freundii; Cg: Candida glabrata; Cgl: Corynebacterium glutamicum; Ck: Candida krusei; Cs: Chlorella sorokiniana; Csp; Cladosporium sp.; Ct: Candida tropicalis; Cv: Chlorella vulgaris; Ea: Enterobacter aerogenes; Ec: Escherichia coli; ECl: Enterobacter cloacae; Eh: Enterococcus hirae; Fsp: Fusarium sp; Gc: Geotrichum candidum; Hi: Haemophilus influenzae; Kp: Klebsiella pneumoniae; Ma: Microsporum audouinii; Mm: Morganella morganii; Mmi: Mucor miehei; Ms: Mycobacterium smegmatis; Mtb: Mycobacterium tuberculosis; Ng: Neisseria gonorrhoeae; Pa: Pseudomonas aeruginosa; Pm: Proteus mirabilis; Pv: Proteus vulgaris; Psp: Penicillium; Pv: Penicillium verrucosum; Sa: Staphylococcus aureus; Sd: Shigella dysenteriae; Sf: Streptococcus faecalis; Sm: Streptococcus mutans; San: Streptococcus anginosus; So: Streptococcus oralis; Spn: Streptococcus pneumoniae; Sp: Streptococcus pyogenes; Sfl: Shigella flexneri; Sp: Streptococcus pneumoniae; Ss: Scenedesmus subspicatus; St: Salmonella typh; Sv : Streptomyces viridochromogenes; Tm: Trichophyton mentagophytes; Tr: Trichophyton rubrum; Va: Vibrio anguillarium; SSp: Staphylococcus saprophyticus; c Plant with no reference for the use in the treatment of infectious diseases, but that extract or derived product showed antimicrobial activity |
It appears from the results of [Table 2] that a number of crude extracts were significantly active. Some of them include extracts of Bersama engleriana, Dorstenia angusticornis, Dorstenia turbinata, Dorstenia barteri, Newbouldia laevis, Vismia laurentii, Vismia guineensis, etc. Numerous active metabolites were isolated from these plants and include several classes.
#Antimicrobial Compounds from Cameroonian Medicinal Plants
Most of the antimicrobial substances isolated from Cameroonian medicinal plants belong to three main classes of secondary metabolites, i.e., terpenoids, phenolic compounds and alkaloids. The classification criterion is highly stringent, but several authors agree to keep the level of 10 µg/mL or 50 µM as the threshold for acceptable activity [30], [31]. In this study, we will set the value as follows: significant activity (MIC < 10 µg/mL), moderate (10 < MIC ≤ 100 µg/mL), and low or negligible (MIC > 100 µg/mL).
#Terpenoids
Terpenoids are the largest and most widespread class of secondary metabolites, mainly in plants and lower invertebrates. A few of them have been used for therapeutic purposes for centuries; but in recent decades the level of research activity in isolating and studying new terpenoids has shown no sign of abating [32]. Generally, terpenoids have low antimicrobial potentials, compared to phenolic compounds. Several terpenoids have been isolated and tested, but a few of them presented an acceptable activity, both antibacterial and antifungal. Nevertheless, some of the terpenoids such as the triterpenoid betulinic acid has been shown to inhibit HIV [33]. Two terpenoids, cymbopogonol and citral showed antifungal activity against C. albicans [34]. Also the diterpenoid trichorabdal A [35] was found to be active against Helicobacter pylori. Plant oils, which contain terpenoids, have shown increasing promise in vivo, inhibiting multiple species of bacteria. For example, cinnamon oil has shown broad-spectrum activity against Pseudomonas aeruginosa [36]. Also, John et al. [37] found that plant oils from Neolitsea foliosa, which also exhibited some antibacterial properties, included sesquiterpenes such as β-caryophyllene. A terpenoid, 3-oxo-(20S,24S)-epoxydammarane 19,25-diacetate isolated from the barks of Caesalpinia pulcherrina also exhibited significant antibacterial activity and a prominent antifungal activity [38]. The mechanism of action of terpenoids is not fully understood but is speculated to involve membrane disruption by the lipophilic compounds. Among the terpenoids isolated from Cameroonian medicinal plants, both hardwiickic acid (1) and friedelin (2) ([Fig. 1]) exhibited interesting antimicrobial effects on gram-positive bacteria and against the gram-negative bacteria [39], [40]. Compound 1 however, presented moderate activity on many other bacterial species and Candida spp. [39]. Compound 2 also presented a significant antibacterial activity against C. freundii, M. morganii, Shigella spp., Proteus spp., P. aeruginosa, Bacillus spp., S. faecalis and Candida spp. [40]. Lupeol and many others triterpenoids were also isolated from Cameroonian plants and tested on a panel of bacteria and yeasts, but most of them exhibited poor activities [41].
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm01.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 1 Antimicrobial terpenoids (1 and 2), arylbenzofurans (14 – 17) and coumarins (44 – 46).
Phenolic compounds
Flavonoids: Several flavonoids isolated from Cameroonian medicinal plants have been reported for their antimicrobial activities ([Fig. 2]). Such compounds comprise largely chalcones, flavones and isoflavones. Chalcones were isolated primarily from plants of the family Moraceae and the genus Dortenia such as Dorstenia angusticornis [42] , Dorstenia elliptica [43] , Dorstenia turbinata [6], and Dorstenia barteri [5]. Among the chalcones, diprenylated compounds such as angusticornin B (3) and bartericin A (4) were reported to be very active vis-à-vis many gram-positive and gram-negative bacteria as well as yeasts such as C. albicans, C. glabrata and C. krusei [42]. It has been demonstrated that hydroxylation of the prenyl groups of stipulin (5) leads to compounds 3 and 4, inducing a significant increase of the antimicrobial activity [42]. Mbaveng et al. [5] also demonstrated that transposition of prenyl from the 5′- (stipulin) to the 3′-position leads to kanzanol C (6), and induces an increase of antimicrobial activity, with compound 6 exhibiting significant antimicrobial activities against M. morganii and S. flexneri while 5 was not so active. A monoprenylated chalcone, isobavachalcone (7), was more active than most of the diprenylated chalcones tested so far, with significant inhibitory effects observed on several bacteria and fungi [5]. Cyclization of this molecule, leading to 4-hydroxylonchocarpin (8), induced a significant reduction of the activity [5]. Kuete et al. [22] also demonstrated that the shift of the prenyl group from C-3 of compound 7 to position 3′ (4,2′,4′-trihydroxy-3-prenylchacone; 9), reduced the specificity of compound 9 against gram-negative bacteria, while activity remained significant on the gram-positive bacteria and yeasts. Also, the absence of prenyl groups leading to 4,2′,4′-trihydroxychacone (10) further reduced this activity. This allows us to conclude that the prenyl group plays an important role in the activity and selectivity of microorganisms to chalcones. Some flavones such as gancaonin Q (11) and kaempferol (12) were significantly active against E. aerogenes, S. dysenteriae and Bacillus spp. [40], [42]. Several other flavonoids have shown moderate antimicrobial activities. This includes luteolin, catechin, epiafzelcetin, phyllocoumarin, amentoflavone, artocarpesin, and cycloartocarpesin [5], [22], [42], [44], [45]. Many bioactive isoflavonoids were also isolated from Cameroonian medicinal plants. Although isoflavonoids such as laburnetin (13) [44] showed significant activity against M. tuberculosis, activities against gram-positive and gram-negative bacteria and fungi, and those of genistein, alpium isoflavone, 2′-hydroxyisoprunetin, 6,7-(2-isopropenylfuro)-5,2′,4′-trihydroxyisoflavone and cajanin were found to be selective, moderate or negligible [44], [45]. Similarly to chalcones, it has also been demonstrated that the cyclization of flavones (e.g., artocarpesin to cycloartocarpesin) reduced the antimicrobial activity [45].
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm02.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 2 Antimicrobial flavonoids (3 – 13).
Arylbenzofuran: Arylbenzofurans ([Fig. 1]) were isolated from Morus mesozygia, including 2-arylbenzofurans of the moracin series (C, M, Q, R, S, T and U) [45], [46]. Although very few arylbenzofurans have so far been isolated, it has been shown that compounds of the moracin series have moderate activities. Nevertheless, some of them such as moracin T (14) were very active (MIC < 10 µg/mL) on E. coli, S. dysenteriae, P. aeruginosa, K. pneumoniae, S. typhi, B. cereus, S. aureus, S. faecalis, and C. albicans [45]. Significant activities of moracin M (15) against P. aeruginosa, moracin U (16) against E. coli, and B. cereus and moracin C (17) against S. dysenteriae, P. aeruginosa and S. typhi were also reported [45]. The antimicrobial activities of other 2-arylbenzofurans such as 6,6′-dihydroxy-4′-methoxy-2-arylbenzofuran, cicerfuran and benzofuran derivatives [46] have, however, been documented [47]. Kuete et al. [45] demonstrated that the prenylation of arylbenzofuran increases the antimicrobial activity, with monoprenylated compounds being generally more active. Similarly to chalcones and flavones, it was shown that the degree of activity depends on the position of the prenyl group, with compound 14 (with C-4 prenylation) being more active than compound 17 (with C-4′ prenylation) [45]. It was also reported that the cyclization of arylbenzofurans reduces their antimicrobial activities [45].
Quinones: Several naphthoquinones isolated from Cameroonian medicinal plants were reported for their activities against bacteria and fungi ([Fig. 3]). MICs < 10 µg/mL were documented for many of them including lapachol (18), 2-acetylfuro-1,4-naphthoquinone (19), 2-hydroxy-3-methoxy-9,10-dioxo-9,10-dihydroanthracene-1-carbaldehyde (20), newbouldiaquinone (21) [48]. Very interesting activities of plumbagin (22), diospyrone (23) and crassiflorone (24) were reported against M. tuberculosis, M. smegmatis and N. gonorrhoeae [49]. Several other quinones ([Fig. 3]) also demonstrated significant antifungal and antibacterial activities, namely newbouldiaquinone A (25), vismiaquinone C (26), vismiaquinone (27), 3-geranyloxy-6-methyl-1,8-dihydroxyanthraquinone (28), 1,8-dihydroxy-6-methoxy-3-methylanthraquinone (29), and bivismiaquinone (30) [40], [48]. Despite the important structural differences between these quinones, the antibacterial and antifungal activities were found to be significant and close to each other, indicating that the presence of the skeleton of naphthoquinones and anthraquinones is the basis of their antimicrobial activities. It has been demonstrated that quinones complex irreversibly with nucleophilic amino acids of microbial proteins, leading to the loss of function and consequently to the death of the pathogens [50]. The reactivity of cluster-based quinones explains why most of these molecules exert significant antimicrobial activities. However, previous studies [48] also proved that the cyclization and the prenylation of naphthoquinones act on the specificity of the antimicrobial activity.
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm03.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 3 Antimicrobial quinones (18 – 30).
Xanthones: Several xanthones ([Fig. 4]) with good antimicrobial properties have been isolated from various medicinal plants of Cameroon. They have been isolated mostly from plants of the family Guttiferae, including members of the genus Garcinia such as Garcinia smeathmanii [51] and Garcinia polyantha [52], and the genus Vismia such as Vismia laurentii [40], and Vismia guineensis [53]. Many of them, such as cheffouxanthone (31) smeathxanthone B (32) [51], 6-deoxyisojacareubin (33), O 1-demethyl-3′,4′-deoxypsorospermin-3,4′-diol (34), 1,3,7-trihydroxyxanthone (35) [40], laurentixanthone A (36), and laurentixanthone B (37) [54] presented selective and significant activities on several bacteria and yeasts of the genus Candida. Banganxanthone A (38) presented a significant antimycobacterial activity against M. tuberculosis and M. smegmatis [52]. Azebaze et al. [55] reported allaxanthone D (39) as a significantly active antimicrobial xanthone. Other bioactive compounds of this class were also documented. These include 1,3,6,7-tetrahydroxy-2-(3-methylbut-2-enyl)xanthone (40) that was active against E. cloacae, K. pneumoniae, P. aeruginosa, S. faecalis, S. aureus, B. megaterium, B. subtilis and C. glabrata [55]. Compounds such as globulixanthones C (41), D (42) and E (43) also exhibited antimicrobial activities against S. aureus, B. subtilis and Vibrio anguillarium [56].
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm04.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 4 Antimicrobial xanthones (31 – 43).
Coumarins: Several coumarins have antimicrobial properties [57], [58], [59], [60], [61]. They have been found to stimulate macrophages [59], which could have an indirect negative effect on infections. More specifically, coumarin has been used to prevent recurrences of cold sores caused by HSV-1 in humans [57]. Phytoalexins, which are hydroxylated derivatives of coumarins, are produced in carrots in response to fungal infection and can be presumed to have antifungal activity [58]. Osthenol also exhibited good activity against gram-positive bacteria [60]. Most of the coumarins isolated so far from Cameroonian medicinal plants ([Fig. 1]) were found in plants of the genus Treculia (Moraceae), including Treculia africana, Treculia acuminata and Treculia obovoidea [22], [62]. They exhibited moderate antibacterial and antifungal activities [6], [22]. Nevertheless, compounds such as 5-methoxy-3-(3-methyl-2,3-dihydroxybutyl)psoralen (44), 5-methoxy-3-[3-(β-glucopyranosyloxy)-2-hydroxy-3-methylbutyl]psoralen (45) exhibited significant antifungal activities with MIC values comparable to those of nystatin [6]. O-[3-(2,2-Dimethyl-3-oxo-2H-furan-5-yl)butyl]bergaptol (46) also had very good, but selective antimicrobial activities against yeasts of the genus Candida, gram-postive and gram-negative bacteria [22].
Other phenols, benzophenones, ellagic acid derivatives: Several other compounds including simple phenolics, benzophenones, cinnamic and ellagic acid derivatives ([Fig. 5]) were identified as active antimicrobial principles of some Cameroonian medicinal plants. Though simple phenolics such as 4-hydroxy-3-methoxybenzaldehyde, 4-methoxyphenol and 3-hydroxy-4-methoxybenzoic acid had weak inhibitory potentials [22], benzophenones presented better activities [51]. This is the case of guttiferone I (47) with MIC < 10 µg/mL reported on C. freundii, E. cloacae, P. vulgaris, B. megaterium and S. faecalis [51]. Isoxanthochymol (48) also exhibited significant activity against B. cereus and B. stearothermophilus [51]. Ellagic acid (49) and its derivatives 3,4-di-O-methylellagic acid (50) and 3,3′,4′-tri-O-methylellagic acid (51) were significantly active against a wide range of bacteria and yeasts [39].
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm05.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 5 Antimicrobial benzophenones (47, 48), ellagic acid (49) and its derivatives (50, 51), and alkaloids (52 – 58).
Alkaloids
Natural alkaloids are known for their anti-infective activities. A review of anti-HIV compounds of plant origin by Cos et al. [63] summarized published data on several classes of alkaloids including naphthylisoquinoline alkaloid dimers (michellamines A–F [64], [65], nitrogen-containing sugar analogues (castanospermine and 1-deoxynojirimycin) [66], [67], sesquiterpene pyridine alkaloids (triptonines A and B) [68], the β-carboline alkaloid harman [69], and the carbazole alkaloid, siamenol [70]. Diterpene alkaloids, commonly isolated from the plants of the Ranunculaceae, or buttercup [71] family [72], were found to have antimicrobial properties. Berberine, an important representative of the alkaloid group was also found to be active against S. aureus with RNA being suggested as its possible target [73]. Compared with phenolics and terpenoids, very few antimicrobial alkaloids have been isolated so far from Cameroonian medicinal plants. This is due to the fact that few numbers of the plant families contain this class of compounds [74]. Alkaloids from Cameroonian medicinal plants ([Fig. 5]) were mostly isolated in three families including Rutaceae (Tecla afzelii) [34], Caesalpiniaceae (Erythrophleum suaveolens) [75] and Apocynaceae (Tabernaemontana crassa) [76]. The presence of alkaloids in these plant families has also been reported [74]. Amongst the antimicrobial alkaloids ([Fig. 5]) isolated from such plants, norcassaide (52) and norerythrosuaveolide (53) isolated from Erythrophleum suaveolens exerted significant inhibitory (MIC < 10 µg/mL) activities against selected microbial strains like K. pneumoniae, N. gonorrhoeae, C. albicans, and C. krusei [75]. Dehydrocorydalmine (54) and palmatine (55) from Tabernaemontana crassa also presented a good activity on N. gonorrhoeae and C. krusei [76]. Kokusaginine (56), maculine (57) and nkolbisine (58) isolated from the stem bark of Tecla afzelii presented rather low or moderate activities, but MICs below 10 µg/mL were recorded on some bacterial species [41].
#Conclusions
This review, the first of its kind on Cameroonian medicinal plants as potential antimicrobials, is intended to serve as the scientific baseline information for the use of the documented plants, as well as a starting point for future studies, leading to the production of improved plant medicines. The paper also draws attention to some active metabolites, which could probably lead to new antimicrobial drugs. The present review will inevitably show the richness of Cameroon medicinal flora as antimicrobial resources and demonstrates that many of them that are used traditionally are effective. Some of the Cameroonian plant extracts distinguished themselves by their exceptional inhibitory power on both bacteria and fungi. Among these are Bersama engleriana, Dorstenia angusticornis, Dorstenia barteri, Diospyros canaliculata, Diospyros crassiflora, Newbouldia laevis, and Ficus cordata. Some of the isolated compounds were also highly active. This was the case for isobavachalcone, kanzanol C and 4-hydroxylonchocarpin isolated from Dorstenia spp., plumbagin, crassiflorone and diospyrone isolated from Diospyros spp., and also newboudiaquinone, lapachol and newbouldiaquinone isolated from Newbouldia laevis. Some of the bioactive compounds such as diospyrone (23), crassiflorone (24), newboudiaquinone (21), newbouldiaquinone A (25), laurentixanthone A (36), laurentixanthone B (37), norcassaïde (49), norerythrosuaveolide (50) [50], smeathxanthone B (32), cheffouxanthone (31) banganxanthone A (38), moracin T (14), moracin U (16), globulixanthones C (41), D (42) and E (43) and many other compounds were isolated and characterized for the first time in Cameroonian medicinal plants. Presently, there is an urgent necessity for standardizing plant drugs from the investigated plants, as their use is still empirical. There is also an urgent requirement to standardize methods and cut-off points for describing antimicrobial activities, as some authors report activities of extracts at more than 10 mg/mL while others, including ourselves, believe that only MIC values less than 100 µg/mL (for extracts) and 10 µg/mL (for compounds) are worthy of the label active. Other recommendations are to include a parallel screening of mammalian cytotoxicity tests to preclude nonspecific cytotoxicity from being interpreted as antimicrobial efficacy following in vitro screening. This is being done in some studies to provide useful selective data, but few research teams in the country are concerned. The study of the mechanism of action and resistance was initiated in our research team at the University of Dschang on active metabolites or extracts, and we recommend that where antimicrobial testings are going on, this should be a priority.
#Acknowledgements
VK is grateful to Drs. H. M. Poumale Poumale, J. Komguem, R. N. Manfouo, J. Gangoué Pieboji, J. G. Tangmouo, A. T. Mbaveng; (Faculty of Science, University of Yaoundé I) and P. Lunga (University of Dschang) for their support and advice.
#References
- 1 Céspedes C L, Avila G, Martinez A, Serrato B, Calderon-Mugica J C, Salgado-Garciglia R. Antifungal and antibacterial activities of Mexican tarragon (Tagetes lucida). J Agric Food Chem. 2006; 54 3521-3527
- 2 Penso G. Index Plantarum Medicinalium Totius Mundicorunque Synoni Morum. Milano; Organizacione Editoriale Medico Farmaceutica 1982
- 3 Biyiti L, Pesando D, Puiseux-Dao S. Antimicrobial activity of two flavanones isolated from the Cameroonian plant Erythrina sigmoidea. Planta Med. 1988; 54 126-128
- 4 Kuete V, Tangmouo J G, Beng V P, Nguemfo E L, Mofo F, Etoa F X, Lontsi D, Samreen I A. Activités antibactérienne et cytotoxique in vitro de différents extraits des écorces du tronc de Diospyros canaliculata (Ebenaceae). West Afr J Pharmacol Drug Res. 2004; 30 22-25
- 5 Mbaveng A T, Ngameni B, Kuete V, Konga Simo I, Ambassa P, Roy R, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Meyer J J M, Lall N, Beng V P. Antimicrobial activity of the crude extracts and five flavonoids from the twigs of Dorstenia barteri (Moraceae). J Ethnopharmacol. 2008; 116 483-489
- 6 Ngameni B, Kuete V, Konga Simo I, Mbaveng A T, Awoussong P K, Patnam R, Roy R, Ngadjui B T. Antibacterial and antifungal activities of the crude extract and compounds from Dorstenia turbinata (Moraceae). S Afr J Bot. 2009; 75 256-261
- 7 WHO .WHO Guideline for the Assessment of herbal Medicines, WHO expert committee on specification for pharmaceutical preparation. Technical Report series No 863. Geneva; WHO 1996
- 8 GLOBAL: Microbes don't know geography – WHO report. http://www.irinnews.org/Report.aspx?ReportId=73901 Accessed on 2 August 2009
- 9 WHO .International spread of disease threatens public health security: The world health report 2007 focuses on building a safer future. Geneva; 2007 http://www.who.int/mediacentre/news/releases/2007/pr44/en/ Accessed on August 02, 2009
- 10 Zager E M, McNerney R. Multidrug-resistant tuberculosis. BMC Infect Dis. 2008; 8 10
- 11 Cameroon major infectious diseases. http://www.indexmundi.com/cameroon/major_infectious_diseases.html Accessed on August 02, 2009
- 12 Ammah A, Nkuo-Akenji T, Ndip R, Deas J E. An update on concurrent malaria and typhoid fever in Cameroon. Trans R Soc Trop Med Hyg. 1999; 93 127-129
- 13 Noeske J, Kuaban C, Cunin P. Are smear-positive pulmonary tuberculosis patients a 'sentinel' population for the HIV epidemic in Cameroon?. Int J Tuberc Lung Dis. 2004; 8 346-351
- 14 McGaw L J, Lall N, Meyer J J M, Eloff J N. The potential of South African plants against Mycobacterium infections. J Ethnopharmacol. 2008; 119 482-500
- 15 Jones K D J, Hesketh T, Yudkin J. Extensively drug-resistant tuberculosis in sub-Saharan Africa: an emerging public-health concern. Trans R Soc Trop Med Hyg. 2008; 102 219-224
- 16 Donald P R, Sirgel F A, Venter A, Parkin D P, Seifart H I, van deWal B W, Maritz J S, Fourie P B. Early bactericidal activity of antituberculosis agents. Expert Rev Anti Infect Ther. 2003; 1 141-145
- 17 Cragg G M, Newman D J, Snader K M. Natural products in drug discovery and development. J Nat Prod. 1997; 60 52-60
- 18 Cowan M M. Plant products as antimicrobial agents. Clin Microbiol Rev. 1999; 12 564-582
- 19 Chung G A C, Aktar Z, Jackson S, Duncan K. High-throughput screen for detecting antimycobacterial agents. Antimicrob Agents Chemother. 1995; 39 2235-2238
- 20 Eloff J N. A sensitive and quick microplate method to determine the minimal inhibitory concentration of plant extracts for bacteria. Planta Med. 1998; 64 711-713
- 21 Babula P, Adam V, Kizek R, Sladky Z, Havel L. Naphthoquinones as allelochemical triggers of programmed cell death. Environ Exp Bot. 2009; 65 330-337
- 22 Kuete V, Metuno R, Ngameni B, Tsafack A M, Ngandeu F, Fotso G W, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Beng V P. Antimicrobial activity of the methanolic extracts and compounds from Treculia obovoidea (Moraceae). J Ethnopharmacol. 2007; 112 531-536
- 23 Adjanohoun J E, Aboubakar N, Dramane K, Ebot M E, Ekpere J A, Enow-Orock E G, Focho D, Gbile Z E, Kamanyi A, Kamsu Ko J, Keita A, Mbenkum T, Mbi C N, Mbiele A L, Mbome I L, Miburu N K, Nancy W L, Nkongmeneck B, Satabie B, Sofowora A, Tamze V, Wirmum C K. Traditional Medicine and Pharmacopoeia: Contribution to ethnopharmacological and floristic Studies in Cameroon. Lago; OAU/STRC 1996: 299
- 24 Tekeu J C. Rapport sur la Pratique des Etudes d'Impact Environnemental (EIE) au Cameroun. Préparé pour la Commission Economique pour l'Afrique de Nations Unies. 2004 http://www.uneca.org/sdd/documents/ReportEIACameroonFinal.pdf Accessed on August 03, 2008
- 25 Aligiannis N, Kalpotzakis E, Mitaku S, Chinou I B. Composition and antimicrobial activity of the essential oils of two Origanum species. J Agric Food Chem. 2001; 40 4168-4170
- 26 Jimenez-Arellanes A, Meckes M, Ramirez R, Torres J, Luna-Herrera J. Activity against multidrug-resistant Mycobacterium tuberculosis in Mexican plants used to treat respiratory diseases. Phytother Res. 2003; 17 903-908
- 27 Tosun F, Akyüz K C, Sener B, Vural M, Palittapongarnpim P. Antimycobacterial screening of some Turkish plants. J Ethnopharmacol. 2004; 95 273-275
- 28 Molina-Salinas G M, Ramos-Guerra M C, Vargas-Villarreal J, Mata-Cardenas B D, Becerril-Montes P, Said-Fernández S. Bactericidal activity of organic extracts from Flourensia cernua DC against strains of Mycobacterium tuberculosis. Arch Med Res. 2006; 37 45-49
- 29 Borges-Argáez R, Canche-Chay C I, Peña-Rodríguez L M, Salvador Said-Fernández S, Molina-Salinas G M. Antimicrobial activity of Diospyros anisandra. Fitoterapia. 2007; 78 370-372
- 30 Rios J L, Recio M C. Medicinal plants and antimicrobial activity. J Ethnopharmacol. 2005; 100 80-84
- 31 Cos P, Maes L, Sindambiwe J B, Vlietinck A J, Berghe V D. Bioassays for antibacterial and antifungal activities. Biological screening of plant constituents. Training manual. Trieste; UNIDO-ICS (United Nations Industrial Development Organization and the International Centre for Science and High Technology) 2006: 19-28
- 32 De las Heras B, Rodríguez B, Boscá L, Villar A M. Terpenoids: sources, structure elucidation and therapeutic potential in inflammation. Curr Top Med Chem. 2003; 3 171-185
- 33 Fujioka T, Kashiwada Y. Anti-AIDS agents. 11. Betulinic acid and platanic acid as anti-HIV principles from Syzigium claviflorum, and the anti-HIV activity of structurally related triterpenoids. J Nat Prod. 1994; 57 243-247
- 34 Ragasa C Y, Ha H K, Hasika M, Maridable J B, Gaspillo P D, Rideout J A. Antimicrobial and cytotoxic terpenoids from Cymbopogon citratus Stapf. Philipp Sci. 2008; 45 111-122
- 35 Kadota S, Basnet P, Ishii E, Tamura T, Namba T. Antibacterial activity of trichorabdal from Rabdosia trichocarpa against Helicobacter pylori. Zentralbl Bakteriol. 1997; 286 63-67
- 36 Prabuseenivasan S, Jayakumar M, Ignacimuthu S. In vitro antibacterial activity of some plant essential oils. BMC Complement Altern Med. 2006; 6 39
- 37 John A J, Karunakran V P, George V. Chemical composition an antibacterial activity of Neolitsea foliosa (Nees) Gamble var. caesia (Meisner) Gamble. J Essent Oil Res. 2007; 19 498-500
- 38 Nasimul Islam A K M, Abas Ali M, Sayeed A, Syed M, Salam A. An antibacterial terpenoid from Caesalpinia pulcherrina Swartz.: its characterization, antimicrobial and cytotoxic activities. Asian J Plant Sci. 2003; 2 1162-1665
- 39 Kuete V, Wabo G F, Ngameni B, Tsafack A M, Metuno R, Etoa F X, Ngadjui B T, Beng V P. Antimicrobial activity of the methanolic extract and compounds from the stem bark of Irvingia gabonensis (Ixonanthaceae). J Ethnopharmacol. 2007; 114 54-60
- 40 Kuete V, Nguemeving J R, Beng V P, Azebaze A G B, Etoa F X, Meyer M, Bodo B, Nkengfack A E. Antimicrobial activity of the methanolic extracts and compounds from Vismia laurentii De Wild (Guttiferae). J Ethnopharmacol. 2007; 109 372-379
- 41 Kuete V, Wansi J D, Mbaveng A T, Kana Sop M M, Tadjong A T, Beng V P, Etoa F X, Wandji J, Meyer J J M, Lall N. Antimicrobial activity of the methanolic extract and compounds from Teclea afzelii (Rutaceae). S Afr J Bot. 2008; 74 572-576
- 42 Kuete V, Simo I K, Beng V P, Bigoga J D, Kapguep R N, Etoa F X, Ngadjui B T. Antimicrobial activity of the methanolic extract, fractions and four flavonoids from the twigs of Dorstenia angusticornis Engl. (Moraceae). J Ethnopharmacol. 2007; 112 271-277
- 43 Kuete V, Ngameni B, Tsafack A M, Ambassa I K, Simo P, Roy R, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Beng V P. Antimicrobial activity of the extract from the twigs of Dorstenia elliptica (Moraceae). Pharmacologyonline. 2007; 1 573-580
- 44 Kuete V, Ngameni B, Fotso Simo C C, Kengap Tankeu R, Tchaleu Ngadjui B, Meyer J J M, Lall N, Kuiate J R. Antimicrobial activity of the crude extracts and compounds from Ficus chlamydocarpa and Ficus cordata (Moraceae). J Ethnopharmacol. 2008; 120 17-24
- 45 Kuete V, Fozing D C, Kapche W F G D, Mbaveng A T, Kuiate J R, Ngadjui B T, Abegaz B M. Antimicrobial activity of the methanolic extract and compounds from Morus mesozygia stem bark. J Ethnopharmacol. 2009; 124 551-555
- 46 Kapche G D W F, Fozing C D, Donfack J H, Fotso F W, Amadou D, Tchana A N, Bezabih M, Moundipa P F, Ngadjui B T, Abegaz B M. Moracin Q–U, new antioxidant prenylated arylbenzofuran derivatives from Morus mesosygia. Phytochemistry. 2009; 70 216-221
- 47 Aslam S N, Stevenson P C, Kokubun T, Hall D R. Antibacterial and antifungal activity of cicerfuran and related 2-arylbenzofurans and stilbenes. Microbiol Res. 2009; 164 191-195
- 48 Kuete V, Eyong K O, Beng V P, Folefoc G N, Hussain H, Krohn K, Nkengfack A E, Saeftel M, Sarite S R, Hoerauf A. Antimicrobial activity of the methanolic extract and compounds isolated from the stem bark of Newbouldia laevis Seem. (Bignoniaceae). Pharmazie. 2007; 62 552-556
- 49 Kuete V, Tangmouo J G, Marion Meyer J J, Lall N. Diospyrone, crassiflorone, and plumbagin, three antimycobacterial and anti-gonorrheal naphthoquinones from two Diospyros species. Int J Antimicrob Agents. 2009; 34 322-325
- 50 Stern J L, Hagerman A E, Steinberg P D, Mason P K. Phorotannin protein interactions. J Chem Ecol. 1996; 22 1887-1889
- 51 Kuete V, Komguem J, Beng V P, Tangmouo J G, Meli A L, Etoa F X, Lontsi D. Antimicrobial components of the methanolic extract from the stem bark of Garcinia smeathmannii Oliver (Clusiaceae). S Afr J Bot. 2007; 73 347-354
- 52 Kuete V, Meli A L, Komguem J, Louh G N, Tangmouo J G, Lontsi D, Marion Meyer J J, Lall N. Antimycobacterial, antibacterial and antifungal activities of the methanolic extract and compounds from Garcinia polyantha. Pharmacologyonline. 2007; 3 87-95
- 53 Mbaveng A T, Kuete V, Nguemeving J R, Krohn K, Nkengfack A E, Meyer J J M, Lall N. Antimicrobial activity of the extracts and compounds from Vismia guineensis (Guttiferae). AJTM. 2008; 3 211-223
- 54 Nguemeving J R, Azebaze A G B, Kuete V, Carly N N E, Beng V P, Meyer M, Bodo B, Nkengfack A E. Laurentixanthones A and B, antimicrobial xanthones from Vismia laurentii. Phytochemistry. 2006; 67 1341-1346
- 55 Azebaze A G B, Ouahouo B M W, Vardamides J C, Valentin A, Kuete V, Acebey L, Beng V P, Nkengfack A E, Meyer M. Allaxanthones A and B, antimicrobial xanthones from Allablackia gabonensis. Nat Prod Res. 2008; 4 333-341
- 56 Nkengfack A E, Mkounga P, Meyer M, Omum Z T, Bodo B. Globulixanthones C, D and E: three prenylated xanthones with antimicrobial properties from the root bark of Symphonia globulifera. Phytochemistry. 2002; 61 181-187
- 57 Berkada B. Preliminary report on warfarin for the treatment of Herpes simplex. J Ir Coll Physicians Surg. 1978; 22 56
- 58 Hoult J R S, Paya M. Pharmacological and biochemical actions of simple coumarins: natural products with therapeutic potential. Gen Pharmacol. 1996; 27 713-722
-
59 Casley-Smith J R, Casley-Smith J R.
Coumarin in the treatment of lymphoedema and other high-protein oedemas. O'Kennedy R, Thornes RD Coumarins: biology, applications and mode of action. New York; John Wiley and Sons, Inc. 1997: 348 - 60 De Souza S M, Monache F D, Smania Jr A. Antibacterial activity of coumarins. Z Naturforsch C. 2005; 60 693-700
- 61 Razavi S M, Imanzadeh G, Davari M. Coumarins from Zosima absinthifolia seeds, with allelopatic effects. EurAsia J BioSci. 2010; 4 17-22
- 62 Kuete V, Metuno R, Ngameni B, Tsafack A M, Ngandeu F, Fotso G W, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Beng V P. Antimicrobial activity of the methanolic extracts and compounds from Treculia obovoidea (Moraceae). S Afr J Bot. 2008; 74 111-115
- 63 Cos P, Maes L, Vlietinck A, Pieters L. Plant-derived leading compounds for chemotherapy of human immunodefiency virus (HIV) infection – an update (1998–2007). Planta Med. 2008; 74 1323-1337
- 64 Hallock Y F, Manfredi K, Dai J, Cardellina II J H, Gulakowski R J, McMahon J B, Schäffer M, Stahl M, Gulden K P, Bringmann G, François G, Boyd M R. Michellamines D–F, new HIV-inhibitory dimeric naphthylisoquinoline alkaloids, and korupensamine E, a new antimalarial monomer, from Ancistrocladus korupensis. J Nat Prod. 1997; 60 677-683
- 65 White E L, Chao W R, Ross L J, Borhani D W, Hobbs P D, Upender V, Dawson M I. Michellamine alkaloids inhibit protein kinase C. Arch Biochem Biophys. 1999; 365 25-30
- 66 Karpas A, Fleet G W J, Dwek R A, Petursson S, Namgoong S K, Ramsden N G, Jacob G S, Rqdemqcher T W. Aminosugar derivatives as potential anti-human immunodeficiency virus agents. Proc Natl Acad Sci USA. 1988; 85 9229-9233
- 67 Watson A A, Fleet G W J, Asano N, Molyneux R J, Nash R J. Polyhydroxylated alkaloids – natural occurrence and therapeutic applications. Phytochemistry. 2001; 56 265-295
- 68 Duan H, Takaishi Y, Imakura Y, Jia Y, Li D, Cosentino M, Lee K H. Sesquiterpene alkaloids from Tripterygium hypoglaucum and Tripterygium wilfordii: a new class of potent anti-HIV agents. J Nat Prod. 2000; 63 357-361
- 69 Ishida J, Wang H K, Oyama M, Cosentino M L, Hu C Q, Lee K H. Anti-AIDS agents. 46. Anti-HIV activity of harman, an anti-HIV principle from Symplocos setchuensis, and its derivatives. J Nat Prod. 2001; 64 958-960
- 70 Meragelman K M, McKee T C, Boyd M R. Siamenol, a new carbazole alkaloid from Murraya siamensis. J Nat Prod. 2000; 63 427-428
- 71 Jones Jr S B, Luchsinger A E. Plant systematics. New York; McGraw-Hill Book Co. 1986
- 72 Atta-ur-Rahman, Choudhary M I. Diterpenoid and steroidal alkaloids. Nat Prod Rep. 1995; 12 361-379
- 73 Yi Z B, Yu Y, Liang Y Z, Zeng B. Evaluation of the antimicrobial mode of berberine by LC/ESI-MS combined with principal component analysis. J Pharm Biomed Anal. 2007; 44 301-304
- 74 Bruneton J. Pharmacognosie: Phytochimie, Plantes medicinales, 3rd edition. Paris; Tec & Doc 1999: 263-309
- 75 Ngounou F N, Manfouo R N, Tapondjou L A, Lontsi D, Kuete V, Penlap V, Etoa F X, Dubois M A L, Sondengam B L. Antimicrobial diterpenoid alkaloids from Erythrophleum suaveolens (Guill. & Perr.) Brenan. Bull Chem Soc Ethiop. 2005; 19 221-226
- 76 Kuete V. Evaluation des propriétés antimicrobiennes de deux plantes médicinales Camerounaises utilises dans le traitement des maladies infectieuses: Solanum trvum (Solanaceae) et Tabernaemontana crassa (Apocynaceae) [dissertation]. Yaoundé; Université de Yaoundé I 2005
- 77 Tatsadjieu L N, Essia Ngang J J, Ngassoum M B, Etoa F X. Antibacterial and antifungal activity of Xylopia aethiopica, Monodora myristica, Zanthoxylum xanthoxyloïdes and Zanthoxylum leprieurii from Cameroon. Fitoterapia. 2003; 74 469-472
- 78 Burkill H M. The Useful plants of west tropical Africa, Vol. 1. Kew; Royal Botanic Gardens 1985: 186-187
- 79 Wagner W L, Herbst D R, Sohmer S H. Manual of the Flowering Plants of Hawaii: revised ed. Honolulu; University of Hawaii Press 1999: 312
- 80 Ngo Teke G, Kuiate J R, Ngouateu O B, Gatsing D. Antidiarrhoeal and antimicrobial activities of Emilia coccinea (Sims) G. Don extracts. J Ethnopharmacol. 2007; 112 278-283
- 81 Ndom J C, Mbafor J T, Wansi J D, Kamdem A W, Meva'a L M, Vardamides J C, Toukam F, Pegyemb D, Ngando T M, Laatsch H, Fomum Z T. Sesquiterpene lactones from Crepis cameroonica (Asteraceae). Nat Prod Res. 2006; 20 435-442
- 82 Eyong K O, Folefoc G N, Kuete V, Beng V P, Krohn K, Hussain H, Nkengfack A E, Saeftel M, Sarite S R, Hoerauf A. Newbouldiaquinone A: a naphthoquinone-anthraquinone ether coupled pigment, as a potential antimicrobial and antimalarial agent from Newbouldia laevis. Phytochemistry. 2006; 67 605-609
- 83 Eyong O K, Krohn K, Hussain H, Folefoc N G, Nkengfack A E, Schulz B, Hu Q. Newboudiaquinone and newboudiamide: A naphthoquinone-anthraquinone couple pigment and a new ceramide from Newboudia laevis. Chem Pharm Bull. 2005; 53 616-619
- 84 Lenta B N, Weniger B, Antheaume C, Noungoue D T, Ngouela S, Assob J C N, Vonthron-Sénécheau C, Fokou P A, Devkota K P, Tsamo E, Sewald N. Anthraquinones from the stem bark of Stereospermum zenkeri with antimicrobial activity. Phytochemistry. 2007; 68 1595-1599
- 85 Hutchinson J, Dalziel J M. Flora of West Tropical Africa, 2nd edition. London; Crown Agents 1958
- 86 Tangmouo J G, Lontsi D, Ngounou F N, Kuete V, Meli A L, Manfouo R N, Kamdem H W, Tane P, Beng V P, Sondengam B L, Connolly J D. Diospyrone, a new coumarinylbinaphthoquinone from Diospyros canaliculata (Ebenaceae): structure and antimicrobial activity. Bull Chem Soc Ethiop. 2005; 19 81-88
- 87 Tangmouo J G, Meli A L, Komguem J, Kuete V, Ngounou F N, Lontsi D, Beng V P, Choudhary M I, Sondengam B L. Crassiflorone, a new naphthoquinone from Diospyros crassiflora (Hien). Tetraedron Lett. 2006; 47 3067-3070
- 88 Dzoyem J P, Tangmouo J G, Lontsi D, Etoa F X, Lohoue P J. In vitro antifungal activity of extract and plumbagin from the stem bark of Diospyros crassiflora Hiern (Ebenaceae). Phytother Res. 2007; 21 671-674
- 89 Dimo T, Laure N E, Benoit N T, Anatole A G B, Paul A A, Emmanuel T V, Pierre K. Antinociceptive and anti-inflammatory effects of the ethyl acetate stem bark extract of Bridelia scleroneura (Euphorbiaceae). Inflammopharmacology. 2006; 14 42-47
- 90 Ngueyem T A, Brusotti G, Marrubini G, Grisoli P, Dacarro C, Vidari G, Finzi P V, Caccialanza G. Validation of use of a traditional remedy from Bridelia grandis (Pierre ex Hutch) stem bark against oral Streptococci. J Ethnopharmacol. 2008; 120 13-16
- 91 Dalziel J M. The useful plants of west tropical Africa. London; The Crown Agents for the Colonies 1937: 140-141
- 92 Talla E, Djamen D, Djouldé D R, Tatsadjeu L, Tantoh D, Mbafor J T, Fomum Z T. Antimicrobial activity of Bridelia ferruginea leaves extracts. Fitoterapia. 2002; 73 343-345
- 93 Kamgang R, Pouokam Kamgne E V, Fonkoua M C, Beng V P, Biwolé S M. Activities of aqueous extracts of Mallotus oppositifolium on Shigella dysenteriae A1-induced diarrhoea in rats. Clin Exp Pharm Physiol. 2006; 33 89-94
- 94 Awouafack M D, Kouam F S, Hussain H, Ngamga D, Tane P, Schulz B, Green I R, Krohn K. Antimicrobial prenylated dihydrochalcones from Eriosema glomerata. Planta Med. 2008; 74 50-54
- 95 Ouahouo B M W, Azebaze A G B, Meyer M, Bodo B, Fomum Z T, Nkengfack A E. Cytotoxic and antimicrobial coumarins from Mammea africana. Ann Trop Med Parasitol. 2004; 98 733-739
- 96 Yimdjo M C, Azebaze A G B, Nkengfack A E, Meyer A M, Bodo B, Fomum Z T. Antimicrobial and cytotoxic agents from Calophyllum inophyllum. Phytochemistry. 2004; 65 2789-2795
- 97 Akoachere J F, Ndip R N, Chenwi E B, Ndip L M, Njock T E, Anong D N. Antibacterial effect of Zingiber officinale and Garcinia kola on respiratory tract pathogens. East Afr Med J. 2002; 79 588-592
- 98 Ngoupayo J, Tabopda T K, Shaiq Ali M. Antimicrobial and immunomodulatory properties of prenylated xanthones from twigs of Garcinia staudtii. Bioorg Med Chem. 2009; 17 5688-5695
- 99 Aubreville A. Flore forestière soudano-guinéenne A.O.F. Cameroun-A.E.F. Paris; Société d'Edition Géographique Maritime et Coloniales 1950: 148-150
- 100 Ngouela S, Ndjakou B L, Tchamo D N, Zelefack F, Tsamo E, Connolly J D. A prenylated xanthone with antimicrobial activity from the seeds of Symphonia globulifera. Nat Prod Res. 2002; 19 23-27
- 101 Menan H, Banzouzi J T, Hocquette A, Pelissier Y, Blache Y, Kone M, Mallie M, Ake Assi L, Valentin A. Antiplasmodial activity and cytotoxicity of plants used in West African traditional medicine for the treatment of malaria. J Ethnopharmacol. 2006; 105 131-136
- 102 Tamokou J D D, Tala M F, Wabo H K, Kuiate J R, Tane P. Antimicrobial activities of methanol extract and compounds from stem bark of Vismia rubescens. J Ethnopharmacol. 2009; 124 571-575
- 103 Berhaut J. Flore illustrée du Sénégal, Dicotylédones, Linacées à Nymphéacées, Tome VI. Dakar; Gouvernement du Sénégal, Ministère du Développement Rural et de l'Hydraulique, Direction des eaux et Forêts 1979: 466-481
- 104 Adamson I, Okafor C, Abu-Bakare A. A supplement of Dikanut (Irvingia gabonensis) improves treatment of type II diabetics. West Afr J Med. 1990; 9 108-115
- 105 Okolo C, Johnson P, Abdulrahman F, Abdu-Aguye I, Hussaini I. Analgesic effect of Irvingia gabonensis stem bark extract. J Ethnopharmacol. 1995; 45 125-129
- 106 Adamson I, Okafor C, Abu-Bakare A. Erythrocyte membrane ATPases in diabetes: effect of Dikanut (Irvingia gabonensis). Enzyme. 1986; 36 212-215
- 107 Ngondi J, Oben J, Minka S. The effect of Irvingia gabonensis seeds on body weight and blood lipids of obese subject in Cameroon. Lipids Health Dis. 2005; 4 12
- 108 Ngassoum M B, Essia-Ngang J J, Tatsadjieu L N, Jirovetz L, Buchbauer G, Adjoudjia O. Antimicrobial study of essential oils of Ocimum gratissimum leaves and Zanthoxylum xanthoxyloides fruits from Cameroon. Fitoterapia. 2003; 74 284-287
- 109 Nguefack J, Lekagne Dongmo J B, Dakole C D, Leth V, Vismer H F, Torp J, Guemdjom E F N, Mbeffo M, Tamgue O, Fotio D, Amvam Zollo P H, Nkengfack A E. Food preservative potential of essential oils and fractions from Cymbopogon citratus, Ocimum gratissimum and Thymus vulgaris against mycotoxigenic fungi. Int J Food Microbiol. 2009; 131 151-156
- 110 Chouna J R, Nkeng-Efouet P A, Lenta B N, Devkota P K, Neumann B, Stammler H G, Kimbu S F, Sewald N. Antibacterial endiandric acid derivatives from Beilschmiedia anacardioides. Phytochemistry. 2009; 70 684-688
- 111 Thomas D W, Thomas J M, Bromely W A, Mbenkum F T. Korup ethnobotany survey: WWF Survey. 1989: A31
- 112 Abegaz B M, Ngadjui T B, Dongo E, Tamboue H. Prenylated chalcones and flavones from the leaves of Dorstenia kameruniana. Phytochemistry. 1998; 49 1147-1150
- 113 Tsopmo A, Tene M, Kamnaing P, Ayafor J F, Sterner A. A new Diels-Alder type adduct flavonoids from D. barteri. J Nat Prod. 1999; 62 1432-1434
- 114 Bouquet A. Féticheurs et médecines traditionnelles du Congo Brazzaville. Paris; Orstom 1969: 178-202
- 115 Kuete V, Nana F, Ngameni B, Mbaveng A T, Keumedjio F, Ngadjui B T. Antimicrobial activity of the crude extract, fractions and compounds from stem bark of Ficus ovata (Moraceae). J Ethnopharmacol. 2009; 124 556-561
- 116 Noumi E, Dibakto T W. Medicinal plants used for peptic ulcer in the Bangangté region, western Cameroon. Fitoterapia. 2002; 71 406-512
- 117 Bokesch H R, Charan R D, Merangelman K M, Beutler J A, Gardella R, O'keefe B R, Mekee T C, Memahon J B. Isolation and characterization of anti-HIV peptides from Dorstenia contrajerva and Treculia obovoidea. FEBS Lett. 2004; 567 287-290
- 118 Kouam S F, Yapna D B, Krohn K, Ngadjui B T, Ngoupayo J, Choudhary M I, Schultz B. Antimicrobial prenylated anthracene derivatives from the leaves of Harungana madagascariensis. J Nat Prod. 2007; 70 600-603
- 119 Vardamides J C, Sielenou V T, Ndemangou B, Nkengfack A E, Fomum Z T, Poumale H M P, Laatsch H. Diterpenoids from Turraeanthus mannii. Planta Med. 2007; 5 491-495
- 120 Njike N E, Watch P, Nguelefack T, Kamanyi A. Hypoglycaemic activity of the leaves extracts of Bersama engleriana in rats. Afr J Trad CAM. 2005; 2 215-221
- 121 Watcho P, Makemdjio A, Nguelefack B T, Kamanyi A. Sexual stimulation effects of the aqueous and methanolic extracts from the leaves of Bersama engleriana in adult male rats. Pharmacologyonline. 2007; 1 464-476
- 122 Kuete V, Tsafack A M, Tsafack M, Beng V P, Etoa F X, Nkengfack A E, Meyer J J M, Lall N. Antitumor, antioxidant and antimicrobial activities of Bersama engleriana (Melianthaceae). J Ethnopharmacol. 2008; 115 494-501
- 123 Zintchem A A, Ngono Bikobo D, Théodore Atchadé A T, Ngo Mbing J, Gangoue-Pieboji J, Ghogomu Tih R, Blond A, Pegnyemb D E, Bodo B. Nitrile glucosides and serotobenine from Campylospermum glaucum and Ouratea turnarea. Phytochemistry. 2008; 69 2209-2213
- 124 Pegnyemb D E, Ngo Mbing J, Atchade A T, Ghogomu Tih R, Sondengam B L, Blond A, Bodo B. Antimicrobial biflavonoids from the aerial parts of Ouratea sulcata. Phytochemistry. 2005; 66 1922-1926
- 125 Irvine R F. Woody plant of Ghana. London; Oxford University Press 1961 223-226 480-481
- 126 Fokou P A, Stammler H G, Neumann B, Huber T, Lontsi D, Kemami Wangun H V, Sewald N. Triterpenes from Maesopsis eminii. J Nat Prod. 2004; 67 2124-2126
- 127 Adnan J A, Mohammad S A, Ilias M, Assad A A, Herman P P. Furoquinoline alkaloids from Teclea nobilis. Phytochemistry. 2003; 66 1405-1411
- 128 Wansi J D, Wandji J, Waffo A F, Ngeufa H E, Ndom J C, Fotso S, Maskey R P, Njamen D, Fomum T Z, Laatsch H. Alkaloids from Oriciopsis glaberrima Engl. (Rutaceae). Phytochemistry. 2006; 67 475-480
- 129 Kuete V, Tangmouo J G, Beng V P, Ngounou M F, Lontsi D. Antimicrobial activity of Tridesmostemon omphalocarpoides Engl. Sapotaceae. J Ethnopharmacol. 2006; 104 5-11
- 130 Megne B C. Contribution à l'étude des plantes médicinales du Camerounieuses: Inventaire de quelques plantes utilisées dans le traitement des MST dans la région de Dschang (Ouest-Cameroun) [Mémoire de Maîtrise]. Dschang; Université de Dschang 1998
- 131 Arthan D, Svasti J, Kittakoop P, Pittayakhachonwut D, Tanticharoen M, Thebtaranonth Y. Antiviral isoflavonoidsulphate and steroidal glycosides from the fruits of Solanum torvum. Phytochemistry. 2002; 59 459-464
- 132 Chah K F, Muko K N, Oboegbulem S I. Antimicrobial activity of methanolic extract of Solanum torvum fruit. Fitoterapia. 2000; 71 187-189
Dr. Victor Kuete
Department of Biochemistry
University of Dschang
P. O. Box 67
Dschang 237
Cameroon
Phone: + 23 7 77 35 59 27
Fax: + 23 72 22 60 18
Email: kuetevictor@yahoo.fr
References
- 1 Céspedes C L, Avila G, Martinez A, Serrato B, Calderon-Mugica J C, Salgado-Garciglia R. Antifungal and antibacterial activities of Mexican tarragon (Tagetes lucida). J Agric Food Chem. 2006; 54 3521-3527
- 2 Penso G. Index Plantarum Medicinalium Totius Mundicorunque Synoni Morum. Milano; Organizacione Editoriale Medico Farmaceutica 1982
- 3 Biyiti L, Pesando D, Puiseux-Dao S. Antimicrobial activity of two flavanones isolated from the Cameroonian plant Erythrina sigmoidea. Planta Med. 1988; 54 126-128
- 4 Kuete V, Tangmouo J G, Beng V P, Nguemfo E L, Mofo F, Etoa F X, Lontsi D, Samreen I A. Activités antibactérienne et cytotoxique in vitro de différents extraits des écorces du tronc de Diospyros canaliculata (Ebenaceae). West Afr J Pharmacol Drug Res. 2004; 30 22-25
- 5 Mbaveng A T, Ngameni B, Kuete V, Konga Simo I, Ambassa P, Roy R, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Meyer J J M, Lall N, Beng V P. Antimicrobial activity of the crude extracts and five flavonoids from the twigs of Dorstenia barteri (Moraceae). J Ethnopharmacol. 2008; 116 483-489
- 6 Ngameni B, Kuete V, Konga Simo I, Mbaveng A T, Awoussong P K, Patnam R, Roy R, Ngadjui B T. Antibacterial and antifungal activities of the crude extract and compounds from Dorstenia turbinata (Moraceae). S Afr J Bot. 2009; 75 256-261
- 7 WHO .WHO Guideline for the Assessment of herbal Medicines, WHO expert committee on specification for pharmaceutical preparation. Technical Report series No 863. Geneva; WHO 1996
- 8 GLOBAL: Microbes don't know geography – WHO report. http://www.irinnews.org/Report.aspx?ReportId=73901 Accessed on 2 August 2009
- 9 WHO .International spread of disease threatens public health security: The world health report 2007 focuses on building a safer future. Geneva; 2007 http://www.who.int/mediacentre/news/releases/2007/pr44/en/ Accessed on August 02, 2009
- 10 Zager E M, McNerney R. Multidrug-resistant tuberculosis. BMC Infect Dis. 2008; 8 10
- 11 Cameroon major infectious diseases. http://www.indexmundi.com/cameroon/major_infectious_diseases.html Accessed on August 02, 2009
- 12 Ammah A, Nkuo-Akenji T, Ndip R, Deas J E. An update on concurrent malaria and typhoid fever in Cameroon. Trans R Soc Trop Med Hyg. 1999; 93 127-129
- 13 Noeske J, Kuaban C, Cunin P. Are smear-positive pulmonary tuberculosis patients a 'sentinel' population for the HIV epidemic in Cameroon?. Int J Tuberc Lung Dis. 2004; 8 346-351
- 14 McGaw L J, Lall N, Meyer J J M, Eloff J N. The potential of South African plants against Mycobacterium infections. J Ethnopharmacol. 2008; 119 482-500
- 15 Jones K D J, Hesketh T, Yudkin J. Extensively drug-resistant tuberculosis in sub-Saharan Africa: an emerging public-health concern. Trans R Soc Trop Med Hyg. 2008; 102 219-224
- 16 Donald P R, Sirgel F A, Venter A, Parkin D P, Seifart H I, van deWal B W, Maritz J S, Fourie P B. Early bactericidal activity of antituberculosis agents. Expert Rev Anti Infect Ther. 2003; 1 141-145
- 17 Cragg G M, Newman D J, Snader K M. Natural products in drug discovery and development. J Nat Prod. 1997; 60 52-60
- 18 Cowan M M. Plant products as antimicrobial agents. Clin Microbiol Rev. 1999; 12 564-582
- 19 Chung G A C, Aktar Z, Jackson S, Duncan K. High-throughput screen for detecting antimycobacterial agents. Antimicrob Agents Chemother. 1995; 39 2235-2238
- 20 Eloff J N. A sensitive and quick microplate method to determine the minimal inhibitory concentration of plant extracts for bacteria. Planta Med. 1998; 64 711-713
- 21 Babula P, Adam V, Kizek R, Sladky Z, Havel L. Naphthoquinones as allelochemical triggers of programmed cell death. Environ Exp Bot. 2009; 65 330-337
- 22 Kuete V, Metuno R, Ngameni B, Tsafack A M, Ngandeu F, Fotso G W, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Beng V P. Antimicrobial activity of the methanolic extracts and compounds from Treculia obovoidea (Moraceae). J Ethnopharmacol. 2007; 112 531-536
- 23 Adjanohoun J E, Aboubakar N, Dramane K, Ebot M E, Ekpere J A, Enow-Orock E G, Focho D, Gbile Z E, Kamanyi A, Kamsu Ko J, Keita A, Mbenkum T, Mbi C N, Mbiele A L, Mbome I L, Miburu N K, Nancy W L, Nkongmeneck B, Satabie B, Sofowora A, Tamze V, Wirmum C K. Traditional Medicine and Pharmacopoeia: Contribution to ethnopharmacological and floristic Studies in Cameroon. Lago; OAU/STRC 1996: 299
- 24 Tekeu J C. Rapport sur la Pratique des Etudes d'Impact Environnemental (EIE) au Cameroun. Préparé pour la Commission Economique pour l'Afrique de Nations Unies. 2004 http://www.uneca.org/sdd/documents/ReportEIACameroonFinal.pdf Accessed on August 03, 2008
- 25 Aligiannis N, Kalpotzakis E, Mitaku S, Chinou I B. Composition and antimicrobial activity of the essential oils of two Origanum species. J Agric Food Chem. 2001; 40 4168-4170
- 26 Jimenez-Arellanes A, Meckes M, Ramirez R, Torres J, Luna-Herrera J. Activity against multidrug-resistant Mycobacterium tuberculosis in Mexican plants used to treat respiratory diseases. Phytother Res. 2003; 17 903-908
- 27 Tosun F, Akyüz K C, Sener B, Vural M, Palittapongarnpim P. Antimycobacterial screening of some Turkish plants. J Ethnopharmacol. 2004; 95 273-275
- 28 Molina-Salinas G M, Ramos-Guerra M C, Vargas-Villarreal J, Mata-Cardenas B D, Becerril-Montes P, Said-Fernández S. Bactericidal activity of organic extracts from Flourensia cernua DC against strains of Mycobacterium tuberculosis. Arch Med Res. 2006; 37 45-49
- 29 Borges-Argáez R, Canche-Chay C I, Peña-Rodríguez L M, Salvador Said-Fernández S, Molina-Salinas G M. Antimicrobial activity of Diospyros anisandra. Fitoterapia. 2007; 78 370-372
- 30 Rios J L, Recio M C. Medicinal plants and antimicrobial activity. J Ethnopharmacol. 2005; 100 80-84
- 31 Cos P, Maes L, Sindambiwe J B, Vlietinck A J, Berghe V D. Bioassays for antibacterial and antifungal activities. Biological screening of plant constituents. Training manual. Trieste; UNIDO-ICS (United Nations Industrial Development Organization and the International Centre for Science and High Technology) 2006: 19-28
- 32 De las Heras B, Rodríguez B, Boscá L, Villar A M. Terpenoids: sources, structure elucidation and therapeutic potential in inflammation. Curr Top Med Chem. 2003; 3 171-185
- 33 Fujioka T, Kashiwada Y. Anti-AIDS agents. 11. Betulinic acid and platanic acid as anti-HIV principles from Syzigium claviflorum, and the anti-HIV activity of structurally related triterpenoids. J Nat Prod. 1994; 57 243-247
- 34 Ragasa C Y, Ha H K, Hasika M, Maridable J B, Gaspillo P D, Rideout J A. Antimicrobial and cytotoxic terpenoids from Cymbopogon citratus Stapf. Philipp Sci. 2008; 45 111-122
- 35 Kadota S, Basnet P, Ishii E, Tamura T, Namba T. Antibacterial activity of trichorabdal from Rabdosia trichocarpa against Helicobacter pylori. Zentralbl Bakteriol. 1997; 286 63-67
- 36 Prabuseenivasan S, Jayakumar M, Ignacimuthu S. In vitro antibacterial activity of some plant essential oils. BMC Complement Altern Med. 2006; 6 39
- 37 John A J, Karunakran V P, George V. Chemical composition an antibacterial activity of Neolitsea foliosa (Nees) Gamble var. caesia (Meisner) Gamble. J Essent Oil Res. 2007; 19 498-500
- 38 Nasimul Islam A K M, Abas Ali M, Sayeed A, Syed M, Salam A. An antibacterial terpenoid from Caesalpinia pulcherrina Swartz.: its characterization, antimicrobial and cytotoxic activities. Asian J Plant Sci. 2003; 2 1162-1665
- 39 Kuete V, Wabo G F, Ngameni B, Tsafack A M, Metuno R, Etoa F X, Ngadjui B T, Beng V P. Antimicrobial activity of the methanolic extract and compounds from the stem bark of Irvingia gabonensis (Ixonanthaceae). J Ethnopharmacol. 2007; 114 54-60
- 40 Kuete V, Nguemeving J R, Beng V P, Azebaze A G B, Etoa F X, Meyer M, Bodo B, Nkengfack A E. Antimicrobial activity of the methanolic extracts and compounds from Vismia laurentii De Wild (Guttiferae). J Ethnopharmacol. 2007; 109 372-379
- 41 Kuete V, Wansi J D, Mbaveng A T, Kana Sop M M, Tadjong A T, Beng V P, Etoa F X, Wandji J, Meyer J J M, Lall N. Antimicrobial activity of the methanolic extract and compounds from Teclea afzelii (Rutaceae). S Afr J Bot. 2008; 74 572-576
- 42 Kuete V, Simo I K, Beng V P, Bigoga J D, Kapguep R N, Etoa F X, Ngadjui B T. Antimicrobial activity of the methanolic extract, fractions and four flavonoids from the twigs of Dorstenia angusticornis Engl. (Moraceae). J Ethnopharmacol. 2007; 112 271-277
- 43 Kuete V, Ngameni B, Tsafack A M, Ambassa I K, Simo P, Roy R, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Beng V P. Antimicrobial activity of the extract from the twigs of Dorstenia elliptica (Moraceae). Pharmacologyonline. 2007; 1 573-580
- 44 Kuete V, Ngameni B, Fotso Simo C C, Kengap Tankeu R, Tchaleu Ngadjui B, Meyer J J M, Lall N, Kuiate J R. Antimicrobial activity of the crude extracts and compounds from Ficus chlamydocarpa and Ficus cordata (Moraceae). J Ethnopharmacol. 2008; 120 17-24
- 45 Kuete V, Fozing D C, Kapche W F G D, Mbaveng A T, Kuiate J R, Ngadjui B T, Abegaz B M. Antimicrobial activity of the methanolic extract and compounds from Morus mesozygia stem bark. J Ethnopharmacol. 2009; 124 551-555
- 46 Kapche G D W F, Fozing C D, Donfack J H, Fotso F W, Amadou D, Tchana A N, Bezabih M, Moundipa P F, Ngadjui B T, Abegaz B M. Moracin Q–U, new antioxidant prenylated arylbenzofuran derivatives from Morus mesosygia. Phytochemistry. 2009; 70 216-221
- 47 Aslam S N, Stevenson P C, Kokubun T, Hall D R. Antibacterial and antifungal activity of cicerfuran and related 2-arylbenzofurans and stilbenes. Microbiol Res. 2009; 164 191-195
- 48 Kuete V, Eyong K O, Beng V P, Folefoc G N, Hussain H, Krohn K, Nkengfack A E, Saeftel M, Sarite S R, Hoerauf A. Antimicrobial activity of the methanolic extract and compounds isolated from the stem bark of Newbouldia laevis Seem. (Bignoniaceae). Pharmazie. 2007; 62 552-556
- 49 Kuete V, Tangmouo J G, Marion Meyer J J, Lall N. Diospyrone, crassiflorone, and plumbagin, three antimycobacterial and anti-gonorrheal naphthoquinones from two Diospyros species. Int J Antimicrob Agents. 2009; 34 322-325
- 50 Stern J L, Hagerman A E, Steinberg P D, Mason P K. Phorotannin protein interactions. J Chem Ecol. 1996; 22 1887-1889
- 51 Kuete V, Komguem J, Beng V P, Tangmouo J G, Meli A L, Etoa F X, Lontsi D. Antimicrobial components of the methanolic extract from the stem bark of Garcinia smeathmannii Oliver (Clusiaceae). S Afr J Bot. 2007; 73 347-354
- 52 Kuete V, Meli A L, Komguem J, Louh G N, Tangmouo J G, Lontsi D, Marion Meyer J J, Lall N. Antimycobacterial, antibacterial and antifungal activities of the methanolic extract and compounds from Garcinia polyantha. Pharmacologyonline. 2007; 3 87-95
- 53 Mbaveng A T, Kuete V, Nguemeving J R, Krohn K, Nkengfack A E, Meyer J J M, Lall N. Antimicrobial activity of the extracts and compounds from Vismia guineensis (Guttiferae). AJTM. 2008; 3 211-223
- 54 Nguemeving J R, Azebaze A G B, Kuete V, Carly N N E, Beng V P, Meyer M, Bodo B, Nkengfack A E. Laurentixanthones A and B, antimicrobial xanthones from Vismia laurentii. Phytochemistry. 2006; 67 1341-1346
- 55 Azebaze A G B, Ouahouo B M W, Vardamides J C, Valentin A, Kuete V, Acebey L, Beng V P, Nkengfack A E, Meyer M. Allaxanthones A and B, antimicrobial xanthones from Allablackia gabonensis. Nat Prod Res. 2008; 4 333-341
- 56 Nkengfack A E, Mkounga P, Meyer M, Omum Z T, Bodo B. Globulixanthones C, D and E: three prenylated xanthones with antimicrobial properties from the root bark of Symphonia globulifera. Phytochemistry. 2002; 61 181-187
- 57 Berkada B. Preliminary report on warfarin for the treatment of Herpes simplex. J Ir Coll Physicians Surg. 1978; 22 56
- 58 Hoult J R S, Paya M. Pharmacological and biochemical actions of simple coumarins: natural products with therapeutic potential. Gen Pharmacol. 1996; 27 713-722
-
59 Casley-Smith J R, Casley-Smith J R.
Coumarin in the treatment of lymphoedema and other high-protein oedemas. O'Kennedy R, Thornes RD Coumarins: biology, applications and mode of action. New York; John Wiley and Sons, Inc. 1997: 348 - 60 De Souza S M, Monache F D, Smania Jr A. Antibacterial activity of coumarins. Z Naturforsch C. 2005; 60 693-700
- 61 Razavi S M, Imanzadeh G, Davari M. Coumarins from Zosima absinthifolia seeds, with allelopatic effects. EurAsia J BioSci. 2010; 4 17-22
- 62 Kuete V, Metuno R, Ngameni B, Tsafack A M, Ngandeu F, Fotso G W, Bezabih M, Etoa F X, Ngadjui B T, Abegaz B M, Beng V P. Antimicrobial activity of the methanolic extracts and compounds from Treculia obovoidea (Moraceae). S Afr J Bot. 2008; 74 111-115
- 63 Cos P, Maes L, Vlietinck A, Pieters L. Plant-derived leading compounds for chemotherapy of human immunodefiency virus (HIV) infection – an update (1998–2007). Planta Med. 2008; 74 1323-1337
- 64 Hallock Y F, Manfredi K, Dai J, Cardellina II J H, Gulakowski R J, McMahon J B, Schäffer M, Stahl M, Gulden K P, Bringmann G, François G, Boyd M R. Michellamines D–F, new HIV-inhibitory dimeric naphthylisoquinoline alkaloids, and korupensamine E, a new antimalarial monomer, from Ancistrocladus korupensis. J Nat Prod. 1997; 60 677-683
- 65 White E L, Chao W R, Ross L J, Borhani D W, Hobbs P D, Upender V, Dawson M I. Michellamine alkaloids inhibit protein kinase C. Arch Biochem Biophys. 1999; 365 25-30
- 66 Karpas A, Fleet G W J, Dwek R A, Petursson S, Namgoong S K, Ramsden N G, Jacob G S, Rqdemqcher T W. Aminosugar derivatives as potential anti-human immunodeficiency virus agents. Proc Natl Acad Sci USA. 1988; 85 9229-9233
- 67 Watson A A, Fleet G W J, Asano N, Molyneux R J, Nash R J. Polyhydroxylated alkaloids – natural occurrence and therapeutic applications. Phytochemistry. 2001; 56 265-295
- 68 Duan H, Takaishi Y, Imakura Y, Jia Y, Li D, Cosentino M, Lee K H. Sesquiterpene alkaloids from Tripterygium hypoglaucum and Tripterygium wilfordii: a new class of potent anti-HIV agents. J Nat Prod. 2000; 63 357-361
- 69 Ishida J, Wang H K, Oyama M, Cosentino M L, Hu C Q, Lee K H. Anti-AIDS agents. 46. Anti-HIV activity of harman, an anti-HIV principle from Symplocos setchuensis, and its derivatives. J Nat Prod. 2001; 64 958-960
- 70 Meragelman K M, McKee T C, Boyd M R. Siamenol, a new carbazole alkaloid from Murraya siamensis. J Nat Prod. 2000; 63 427-428
- 71 Jones Jr S B, Luchsinger A E. Plant systematics. New York; McGraw-Hill Book Co. 1986
- 72 Atta-ur-Rahman, Choudhary M I. Diterpenoid and steroidal alkaloids. Nat Prod Rep. 1995; 12 361-379
- 73 Yi Z B, Yu Y, Liang Y Z, Zeng B. Evaluation of the antimicrobial mode of berberine by LC/ESI-MS combined with principal component analysis. J Pharm Biomed Anal. 2007; 44 301-304
- 74 Bruneton J. Pharmacognosie: Phytochimie, Plantes medicinales, 3rd edition. Paris; Tec & Doc 1999: 263-309
- 75 Ngounou F N, Manfouo R N, Tapondjou L A, Lontsi D, Kuete V, Penlap V, Etoa F X, Dubois M A L, Sondengam B L. Antimicrobial diterpenoid alkaloids from Erythrophleum suaveolens (Guill. & Perr.) Brenan. Bull Chem Soc Ethiop. 2005; 19 221-226
- 76 Kuete V. Evaluation des propriétés antimicrobiennes de deux plantes médicinales Camerounaises utilises dans le traitement des maladies infectieuses: Solanum trvum (Solanaceae) et Tabernaemontana crassa (Apocynaceae) [dissertation]. Yaoundé; Université de Yaoundé I 2005
- 77 Tatsadjieu L N, Essia Ngang J J, Ngassoum M B, Etoa F X. Antibacterial and antifungal activity of Xylopia aethiopica, Monodora myristica, Zanthoxylum xanthoxyloïdes and Zanthoxylum leprieurii from Cameroon. Fitoterapia. 2003; 74 469-472
- 78 Burkill H M. The Useful plants of west tropical Africa, Vol. 1. Kew; Royal Botanic Gardens 1985: 186-187
- 79 Wagner W L, Herbst D R, Sohmer S H. Manual of the Flowering Plants of Hawaii: revised ed. Honolulu; University of Hawaii Press 1999: 312
- 80 Ngo Teke G, Kuiate J R, Ngouateu O B, Gatsing D. Antidiarrhoeal and antimicrobial activities of Emilia coccinea (Sims) G. Don extracts. J Ethnopharmacol. 2007; 112 278-283
- 81 Ndom J C, Mbafor J T, Wansi J D, Kamdem A W, Meva'a L M, Vardamides J C, Toukam F, Pegyemb D, Ngando T M, Laatsch H, Fomum Z T. Sesquiterpene lactones from Crepis cameroonica (Asteraceae). Nat Prod Res. 2006; 20 435-442
- 82 Eyong K O, Folefoc G N, Kuete V, Beng V P, Krohn K, Hussain H, Nkengfack A E, Saeftel M, Sarite S R, Hoerauf A. Newbouldiaquinone A: a naphthoquinone-anthraquinone ether coupled pigment, as a potential antimicrobial and antimalarial agent from Newbouldia laevis. Phytochemistry. 2006; 67 605-609
- 83 Eyong O K, Krohn K, Hussain H, Folefoc N G, Nkengfack A E, Schulz B, Hu Q. Newboudiaquinone and newboudiamide: A naphthoquinone-anthraquinone couple pigment and a new ceramide from Newboudia laevis. Chem Pharm Bull. 2005; 53 616-619
- 84 Lenta B N, Weniger B, Antheaume C, Noungoue D T, Ngouela S, Assob J C N, Vonthron-Sénécheau C, Fokou P A, Devkota K P, Tsamo E, Sewald N. Anthraquinones from the stem bark of Stereospermum zenkeri with antimicrobial activity. Phytochemistry. 2007; 68 1595-1599
- 85 Hutchinson J, Dalziel J M. Flora of West Tropical Africa, 2nd edition. London; Crown Agents 1958
- 86 Tangmouo J G, Lontsi D, Ngounou F N, Kuete V, Meli A L, Manfouo R N, Kamdem H W, Tane P, Beng V P, Sondengam B L, Connolly J D. Diospyrone, a new coumarinylbinaphthoquinone from Diospyros canaliculata (Ebenaceae): structure and antimicrobial activity. Bull Chem Soc Ethiop. 2005; 19 81-88
- 87 Tangmouo J G, Meli A L, Komguem J, Kuete V, Ngounou F N, Lontsi D, Beng V P, Choudhary M I, Sondengam B L. Crassiflorone, a new naphthoquinone from Diospyros crassiflora (Hien). Tetraedron Lett. 2006; 47 3067-3070
- 88 Dzoyem J P, Tangmouo J G, Lontsi D, Etoa F X, Lohoue P J. In vitro antifungal activity of extract and plumbagin from the stem bark of Diospyros crassiflora Hiern (Ebenaceae). Phytother Res. 2007; 21 671-674
- 89 Dimo T, Laure N E, Benoit N T, Anatole A G B, Paul A A, Emmanuel T V, Pierre K. Antinociceptive and anti-inflammatory effects of the ethyl acetate stem bark extract of Bridelia scleroneura (Euphorbiaceae). Inflammopharmacology. 2006; 14 42-47
- 90 Ngueyem T A, Brusotti G, Marrubini G, Grisoli P, Dacarro C, Vidari G, Finzi P V, Caccialanza G. Validation of use of a traditional remedy from Bridelia grandis (Pierre ex Hutch) stem bark against oral Streptococci. J Ethnopharmacol. 2008; 120 13-16
- 91 Dalziel J M. The useful plants of west tropical Africa. London; The Crown Agents for the Colonies 1937: 140-141
- 92 Talla E, Djamen D, Djouldé D R, Tatsadjeu L, Tantoh D, Mbafor J T, Fomum Z T. Antimicrobial activity of Bridelia ferruginea leaves extracts. Fitoterapia. 2002; 73 343-345
- 93 Kamgang R, Pouokam Kamgne E V, Fonkoua M C, Beng V P, Biwolé S M. Activities of aqueous extracts of Mallotus oppositifolium on Shigella dysenteriae A1-induced diarrhoea in rats. Clin Exp Pharm Physiol. 2006; 33 89-94
- 94 Awouafack M D, Kouam F S, Hussain H, Ngamga D, Tane P, Schulz B, Green I R, Krohn K. Antimicrobial prenylated dihydrochalcones from Eriosema glomerata. Planta Med. 2008; 74 50-54
- 95 Ouahouo B M W, Azebaze A G B, Meyer M, Bodo B, Fomum Z T, Nkengfack A E. Cytotoxic and antimicrobial coumarins from Mammea africana. Ann Trop Med Parasitol. 2004; 98 733-739
- 96 Yimdjo M C, Azebaze A G B, Nkengfack A E, Meyer A M, Bodo B, Fomum Z T. Antimicrobial and cytotoxic agents from Calophyllum inophyllum. Phytochemistry. 2004; 65 2789-2795
- 97 Akoachere J F, Ndip R N, Chenwi E B, Ndip L M, Njock T E, Anong D N. Antibacterial effect of Zingiber officinale and Garcinia kola on respiratory tract pathogens. East Afr Med J. 2002; 79 588-592
- 98 Ngoupayo J, Tabopda T K, Shaiq Ali M. Antimicrobial and immunomodulatory properties of prenylated xanthones from twigs of Garcinia staudtii. Bioorg Med Chem. 2009; 17 5688-5695
- 99 Aubreville A. Flore forestière soudano-guinéenne A.O.F. Cameroun-A.E.F. Paris; Société d'Edition Géographique Maritime et Coloniales 1950: 148-150
- 100 Ngouela S, Ndjakou B L, Tchamo D N, Zelefack F, Tsamo E, Connolly J D. A prenylated xanthone with antimicrobial activity from the seeds of Symphonia globulifera. Nat Prod Res. 2002; 19 23-27
- 101 Menan H, Banzouzi J T, Hocquette A, Pelissier Y, Blache Y, Kone M, Mallie M, Ake Assi L, Valentin A. Antiplasmodial activity and cytotoxicity of plants used in West African traditional medicine for the treatment of malaria. J Ethnopharmacol. 2006; 105 131-136
- 102 Tamokou J D D, Tala M F, Wabo H K, Kuiate J R, Tane P. Antimicrobial activities of methanol extract and compounds from stem bark of Vismia rubescens. J Ethnopharmacol. 2009; 124 571-575
- 103 Berhaut J. Flore illustrée du Sénégal, Dicotylédones, Linacées à Nymphéacées, Tome VI. Dakar; Gouvernement du Sénégal, Ministère du Développement Rural et de l'Hydraulique, Direction des eaux et Forêts 1979: 466-481
- 104 Adamson I, Okafor C, Abu-Bakare A. A supplement of Dikanut (Irvingia gabonensis) improves treatment of type II diabetics. West Afr J Med. 1990; 9 108-115
- 105 Okolo C, Johnson P, Abdulrahman F, Abdu-Aguye I, Hussaini I. Analgesic effect of Irvingia gabonensis stem bark extract. J Ethnopharmacol. 1995; 45 125-129
- 106 Adamson I, Okafor C, Abu-Bakare A. Erythrocyte membrane ATPases in diabetes: effect of Dikanut (Irvingia gabonensis). Enzyme. 1986; 36 212-215
- 107 Ngondi J, Oben J, Minka S. The effect of Irvingia gabonensis seeds on body weight and blood lipids of obese subject in Cameroon. Lipids Health Dis. 2005; 4 12
- 108 Ngassoum M B, Essia-Ngang J J, Tatsadjieu L N, Jirovetz L, Buchbauer G, Adjoudjia O. Antimicrobial study of essential oils of Ocimum gratissimum leaves and Zanthoxylum xanthoxyloides fruits from Cameroon. Fitoterapia. 2003; 74 284-287
- 109 Nguefack J, Lekagne Dongmo J B, Dakole C D, Leth V, Vismer H F, Torp J, Guemdjom E F N, Mbeffo M, Tamgue O, Fotio D, Amvam Zollo P H, Nkengfack A E. Food preservative potential of essential oils and fractions from Cymbopogon citratus, Ocimum gratissimum and Thymus vulgaris against mycotoxigenic fungi. Int J Food Microbiol. 2009; 131 151-156
- 110 Chouna J R, Nkeng-Efouet P A, Lenta B N, Devkota P K, Neumann B, Stammler H G, Kimbu S F, Sewald N. Antibacterial endiandric acid derivatives from Beilschmiedia anacardioides. Phytochemistry. 2009; 70 684-688
- 111 Thomas D W, Thomas J M, Bromely W A, Mbenkum F T. Korup ethnobotany survey: WWF Survey. 1989: A31
- 112 Abegaz B M, Ngadjui T B, Dongo E, Tamboue H. Prenylated chalcones and flavones from the leaves of Dorstenia kameruniana. Phytochemistry. 1998; 49 1147-1150
- 113 Tsopmo A, Tene M, Kamnaing P, Ayafor J F, Sterner A. A new Diels-Alder type adduct flavonoids from D. barteri. J Nat Prod. 1999; 62 1432-1434
- 114 Bouquet A. Féticheurs et médecines traditionnelles du Congo Brazzaville. Paris; Orstom 1969: 178-202
- 115 Kuete V, Nana F, Ngameni B, Mbaveng A T, Keumedjio F, Ngadjui B T. Antimicrobial activity of the crude extract, fractions and compounds from stem bark of Ficus ovata (Moraceae). J Ethnopharmacol. 2009; 124 556-561
- 116 Noumi E, Dibakto T W. Medicinal plants used for peptic ulcer in the Bangangté region, western Cameroon. Fitoterapia. 2002; 71 406-512
- 117 Bokesch H R, Charan R D, Merangelman K M, Beutler J A, Gardella R, O'keefe B R, Mekee T C, Memahon J B. Isolation and characterization of anti-HIV peptides from Dorstenia contrajerva and Treculia obovoidea. FEBS Lett. 2004; 567 287-290
- 118 Kouam S F, Yapna D B, Krohn K, Ngadjui B T, Ngoupayo J, Choudhary M I, Schultz B. Antimicrobial prenylated anthracene derivatives from the leaves of Harungana madagascariensis. J Nat Prod. 2007; 70 600-603
- 119 Vardamides J C, Sielenou V T, Ndemangou B, Nkengfack A E, Fomum Z T, Poumale H M P, Laatsch H. Diterpenoids from Turraeanthus mannii. Planta Med. 2007; 5 491-495
- 120 Njike N E, Watch P, Nguelefack T, Kamanyi A. Hypoglycaemic activity of the leaves extracts of Bersama engleriana in rats. Afr J Trad CAM. 2005; 2 215-221
- 121 Watcho P, Makemdjio A, Nguelefack B T, Kamanyi A. Sexual stimulation effects of the aqueous and methanolic extracts from the leaves of Bersama engleriana in adult male rats. Pharmacologyonline. 2007; 1 464-476
- 122 Kuete V, Tsafack A M, Tsafack M, Beng V P, Etoa F X, Nkengfack A E, Meyer J J M, Lall N. Antitumor, antioxidant and antimicrobial activities of Bersama engleriana (Melianthaceae). J Ethnopharmacol. 2008; 115 494-501
- 123 Zintchem A A, Ngono Bikobo D, Théodore Atchadé A T, Ngo Mbing J, Gangoue-Pieboji J, Ghogomu Tih R, Blond A, Pegnyemb D E, Bodo B. Nitrile glucosides and serotobenine from Campylospermum glaucum and Ouratea turnarea. Phytochemistry. 2008; 69 2209-2213
- 124 Pegnyemb D E, Ngo Mbing J, Atchade A T, Ghogomu Tih R, Sondengam B L, Blond A, Bodo B. Antimicrobial biflavonoids from the aerial parts of Ouratea sulcata. Phytochemistry. 2005; 66 1922-1926
- 125 Irvine R F. Woody plant of Ghana. London; Oxford University Press 1961 223-226 480-481
- 126 Fokou P A, Stammler H G, Neumann B, Huber T, Lontsi D, Kemami Wangun H V, Sewald N. Triterpenes from Maesopsis eminii. J Nat Prod. 2004; 67 2124-2126
- 127 Adnan J A, Mohammad S A, Ilias M, Assad A A, Herman P P. Furoquinoline alkaloids from Teclea nobilis. Phytochemistry. 2003; 66 1405-1411
- 128 Wansi J D, Wandji J, Waffo A F, Ngeufa H E, Ndom J C, Fotso S, Maskey R P, Njamen D, Fomum T Z, Laatsch H. Alkaloids from Oriciopsis glaberrima Engl. (Rutaceae). Phytochemistry. 2006; 67 475-480
- 129 Kuete V, Tangmouo J G, Beng V P, Ngounou M F, Lontsi D. Antimicrobial activity of Tridesmostemon omphalocarpoides Engl. Sapotaceae. J Ethnopharmacol. 2006; 104 5-11
- 130 Megne B C. Contribution à l'étude des plantes médicinales du Camerounieuses: Inventaire de quelques plantes utilisées dans le traitement des MST dans la région de Dschang (Ouest-Cameroun) [Mémoire de Maîtrise]. Dschang; Université de Dschang 1998
- 131 Arthan D, Svasti J, Kittakoop P, Pittayakhachonwut D, Tanticharoen M, Thebtaranonth Y. Antiviral isoflavonoidsulphate and steroidal glycosides from the fruits of Solanum torvum. Phytochemistry. 2002; 59 459-464
- 132 Chah K F, Muko K N, Oboegbulem S I. Antimicrobial activity of methanolic extract of Solanum torvum fruit. Fitoterapia. 2000; 71 187-189
Dr. Victor Kuete
Department of Biochemistry
University of Dschang
P. O. Box 67
Dschang 237
Cameroon
Phone: + 23 7 77 35 59 27
Fax: + 23 72 22 60 18
Email: kuetevictor@yahoo.fr
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm01.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 1 Antimicrobial terpenoids (1 and 2), arylbenzofurans (14 – 17) and coumarins (44 – 46).
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm02.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 2 Antimicrobial flavonoids (3 – 13).
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm03.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 3 Antimicrobial quinones (18 – 30).
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm04.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 4 Antimicrobial xanthones (31 – 43).
![](https://www.thieme-connect.de/media/plantamedica/201014/thumbnails/u0130pm05.jpg)
![Zoom Image](/products/assets/desktop/css/img/icon-figure-zoom.png)
Fig. 5 Antimicrobial benzophenones (47, 48), ellagic acid (49) and its derivatives (50, 51), and alkaloids (52 – 58).