title: Biflavonoids with cytotoxic and antibacterial activity from Ochna macrocalyx.
abstract: Six biflavonoid and related compounds were isolated from the ethanolic extract of Ochna macrocalyx bark. One is a new compound, the isoflavanone dimer dehydroxyhexaspermone C ( 1). Previously isolated compounds obtained from the bark are biisoflavonoid hexaspermone C ( 2). tetrahydrofuran derivative ochnone ( 3). furobenzopyran derivative cordigol ( 4). and biflavonoids calodenin B ( 5). and dihydrocalodenin B ( 6). Although 3 has already been isolated, its spectral data are presented here for the first time. Isolated compounds were tested for cytotoxic activity on MCF-7 breast cancer cells using the MTT reduction assay method. Compound 5 showed cytotoxic activity (7 +/- 0.5 microM) and 6 showed moderate cytotoxicity (35 +/- 7 microM). In antibacterial assays performed using three strains of multi-drug resistant (mdr) Staphylococcus aureus (RN4220, XU212 and SA-1199-B) compounds 5 and in particular 6 showed strong antibacterial activity (MICs 5 : 64, 8, 16 microg/mL 6 : 8, 8, 8 microg/mL, respectively). The ethanolic extract of the bark also showed NF-kappaB inhibitory activity.
authors.affiliation: Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, London, UK.
authors.forename: Sharon
authors.initials: S
authors.lastname: Tang
authors.forename: Paul
authors.initials: P
authors.lastname: Bremner
authors.forename: Andreas
authors.initials: A
authors.lastname: Kortenkamp
authors.forename: Christina
authors.initials: C
authors.lastname: Schlage
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Gray
authors.forename: Simon
authors.initials: S
authors.lastname: Gibbons
authors.forename: Michael
authors.initials: M
authors.lastname: Heinrich
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology; D018432:Drug Resistance, Multiple; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D029581:Malpighiaceae; D008826:Microbial Sensitivity Tests; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D008517:Phytotherapy; D024301:Plant Bark; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D000972:Antineoplastic Agents, Phytogenic; D005419:Flavonoids; D016328:NF-kappa B; D010936:Plant Extracts