title: Effect of 7-day daily replacement of culture medium containing Eurycoma longifolia Jack constituents on the Malaysian Plasmodium falciparum isolates.
abstract: Six Malaysian chloroquine-resistant Plasmodium falciparum isolates were cultured in vitro following the candle-jar method. Antimalarial evaluations of daily replacement of culture medium containing chloroquine and a semi-purified extract of Eurycoma longifolia Jack (containing 13 beta, 18-dihydroeurycomanol (1), eurycomanol-2-O-beta-D-glucopyranoside (2), eurycomanol (3) and eurycomanone (4)) were performed on 6-well plates at 37 degrees C for a week. Presence or absence of the parasites was determined microscopically on thin-film Giemsa-stained preparations. Results showed that the antimalarial activity of Eurycoma longifolia Jack was dose-dependent and reached a maximum of < 50% at 0.07-5.00 micrograms ml-1 after 1 day post-treatment. However, complete inhibitions were observed at 1.25-5.00 micrograms ml-1 extract after 3 days post-treatment and 0.62 and 0.31 micrograms ml-1 after 4 and 6 days post-treatment, respectively. Further results indicated that chloroquine exhibited total inhibition at concentrations > 2.50 and 0.62 micrograms ml-1 after 1 and 2 days post-treatment, respectively and at all concentrations after 3 days post-treatment.
authors.affiliation: School of Pharmaceutical Sciences, University Science Malaysia, Penang.
authors.forename: H H
authors.initials: HH
authors.lastname: Ang
authors.forename: K L
authors.initials: KL
authors.lastname: Chan
authors.forename: J W
authors.initials: JW
authors.lastname: Mak
mesh_terms: D000818:Animals; D000962:Antimalarials / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002738:Chloroquine / Q000494:pharmacology; D003470:Culture Media; D005900:Glaucarubin / Q000031:analogs & derivatives / Q000494:pharmacology; D008296:Malaysia; D010936:Plant Extracts / Q000494:pharmacology; D010946:Plants, Medicinal; D010963:Plasmodium falciparum / Q000187:drug effects*; D036702:Quassins
chemical_list: C093530:13,18-dihydroeurycomanol; D000962:Antimalarials; D003470:Culture Media; D010936:Plant Extracts; D036702:Quassins; C093531:eurycomanol 2-O-glucopyranoside; C093532:eurycomanol; D002738:Chloroquine; D005900:Glaucarubin