title: Antimycobacterial and antioxidant flavones from Limnophila geoffrayi.
abstract: The chloroform extract of the aerial part of Limnophila geoffrayi showed antimycobacterial and antioxidant activities. Bioassay-guided fractionation has led to the isolation of the flavones nevadensin (5,7-dihydroxy-6,8,4'-trimethoxyflavone, 1) and isothymusin (6,7-dimethoxy-5,8,4'-trihydroxyflavone, 2). Both compounds 1 and 2 exhibited inhibition activity against Mycobacterium tuberculosis, with equal MIC value of 200 microg/mL. Only compound 2 exhibited antioxidant activity against the radical scavenging ability of DPPH, with the IC50 value of 7.7 microg/mL. The crude hexane, chloroform and methanol extracts as well as the pure compounds 1 and 2 did not exhibit mutagenic activity in the Bacillus subtilis recassay.
authors: Department of Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand. apichart@ram1.ru.ac.th
authors: Apichart
authors: A
authors: Suksamrarn
authors: Ponsuda
authors: P
authors: Poomsing
authors: Nuntana
authors: N
authors: Aroonrerk
authors: Tadsanee
authors: T
authors: Punjanon
authors: Sunit
authors: S
authors: Suksamrarn
authors: Somkiat
authors: S
authors: Kongkun
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D002725:Chloroform / Q000737:chemistry; D047309:Flavones; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests / Q000379:methods; D015394:Molecular Structure; D009152:Mutagenicity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D028083:Scrophulariaceae / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D047309:Flavones; D005419:Flavonoids; D010936:Plant Extracts; C023982:nevadensin; D002725:Chloroform; C487424:isothymusin