title: Antimalarial activity of biflavonoids from Ochna integerrima.
abstract: During the screening of antimalarial substances, the 80% EtOH extract from the outer bark of Ochna integerrima Merr. (Ochnaceae) was shown to have a good anti-malarial activity (IC50 value: 6.5 microg/mL) whereas extracts from the inner barks of O.integerrima showed no antimalarial activity. Biflavanone (1), which had not been found previously from a natural plant source, was isolated as a potent antimalarial active ingredient (IC50 value: 80 ng/mL) from the extract of the outer barks. The stereoisomer of 1 ( = compound 2) was also isolated from this plant; however, its activity was significantly lower than that of 1.
authors.affiliation: Kitasato Institute for Life Sciences, Kitasato University, Tokyo , Japan.
authors.forename: Chikara
authors.initials: C
authors.lastname: Ichino
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kiyohara
authors.forename: Noppamas
authors.initials: N
authors.lastname: Soonthornchareonnon
authors.forename: Wongsatit
authors.initials: W
authors.lastname: Chuakul
authors.forename: Aki
authors.initials: A
authors.lastname: Ishiyama
authors.forename: Hitomi
authors.initials: H
authors.lastname: Sekiguchi
authors.forename: Miyuki
authors.initials: M
authors.lastname: Namatame
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Otoguro
authors.forename: Satoshi
authors.initials: S
authors.lastname: Omura
authors.forename: Haruki
authors.initials: H
authors.lastname: Yamada
mesh_terms: D000962:Antimalarials / Q000032:analysis*; D005419:Flavonoids / Q000737:chemistry; D043842:Ochnaceae / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry*
chemical_list: D000962:Antimalarials; D005419:Flavonoids