Free radicals scavenging and hepatoprotective activities of the rwandese medicinal herb, Crassocephalum vitellinum and composition of the essential oil

The treatment of liver diseases occupies an important place in the Rwandese traditional medicine and several plants or combinations of plants, among which are Crassocephalum vitellinum leaves, are used by the traditional healers. The present work investigates the claimed antihepatotoxic and antioxidant activities of leaves polar extracts, comparing to N-acetyl cysteine (reference antihepatotoxicant) and both quercetin and Trolox (reference antioxidants). In order to evaluate the direct and protective effects of C. vitellinum methanolic extract on liver, rats precision cut liver slices (PCLS) were prepared and incubated in a Williams medium E with 1, 2, 5, 10mg/ml of the extract either alone or in the presence of acetaminophen (hepatotoxicant, 10mM). The measurement of ATP level and CYP2E1 activity were used as endpoints to assess liver toxicity and metabolic activity. Chlorzoxazone was used as a probe to assess CYP2E1 enzymatic activity and the metabolite 6-OH-chlorzoxazone formation was quantified by HPLC [1]. In addition to a significant hepatoprotective activity (1mg/ml), the methanolic extract of C. vitellinum leaves strongly scavenged the stable radical 1, 1-diphenyl-2-picryhydrazyl (DPPH) and reduced the peroxidation of linoleic acid. The essential oil was isolated by hydrodistillation (0,046% v/w yield) and analyzed with GC and GC/MS [2]. Identified predominating constituents that represent 95.8% of the total oil profile are limonene (34.8%), (E)-β-ocimene (21.8%), β-pinene (8.5%), α-pinene (6.6%), myrcene (6.3%), β-phellandrene (5.5%), germacrene-D (4.04%), α-phellandrene (3.6%),terpinolene (1.8%), Sabinene (1.7%), and β-caryophyllene (1.14%).

References: [1] Evdokinova E. et al. (2001) Toxicology in vitro 15: 683–690. [2] Lameck S. et al. (2004) Flavour and Fragrance Journal 20: 316–317