The aim of this work: a cascade method to isolate triterpene acids, flavonoids, phenylpropanoids, iridoid glycosides, polysaccharides from Plantago lanceolata L. cultivated in Romania, in order to further study their possible antagonistic or synergistic actions concerning antiinflammatory and antimicrobial effects.
The dried powdered vegetable material was succesively extracted with dichloromethane, methanol and water in an ultrasound field. The components were isolated as follows: -triterpene acids: from dichloromethane extract through extraction with acetone, ethanol, discolouration and crystallization; -flavonoids: from methanolic extract through extraction with ethyl acetate and CC on a polymeric phase with methanol/water as eluent; -phenylpropanoids and iridoid glycosides: from methanolic and aqueous extracts through extraction with n-butanol and CC on a polymeric phase with a gradient of methanol/water; -polysaccharides: from aqueous extract through precipitation in ethanol, discolouration and repeated precipitations.
Quantification of constituents was carried out through HPLC and TLC using ursolic and oleanolic acid, apigenin-7-glycoside, luteolin-7-glycoside, acteoside, aucubin and catalpol as reference substances.
HPLC -column type: Eurospher 100–5C18, -mobile phase: -methanol/acetonitril/ortho-phosphoric acid pH 2.5 (40/10/50 v/v/v) (flavonoids); -methanol/ortho-phosphoric acid pH 3 (40/60 v/v) (phenylpropanoids); -acetonitril/methanol/water (3/5/92 v/v/v) (iridoids); TLC -stationary phase: Silica gel 60F-254, -mobile phase: -ethyl acetate/formic acid/water (20/2/3 v/v/v) (flavonoids); -ethyl acetate/methanol/10% acetic acid (75/20/5 v/v/v) (phenylpropanoids); -chloroform/methanol/2N acetic acid (70/30/6 v/v/v) (iridoids); -petroleum ether/benzene/ethyl acetate/ethanol (20/10/7/0.5 v/v/v/v) (triterpene acids).
The obtained products are appropriate to be pharmacologically tested.
