Antibacterial and cytotoxic activities of undescribed cassiaric acid and other constituents from Cassia arereh stem barks.

A new lupane-type triterpene, 2α,3ß-dihydroxylupan-29-oic acid (1), and one new ceramide derivative: (2S*,2'R*,3S*,4R*,5R*,7'E,11E,12'E,20E)-N-[2'-hydroxyoctadeca-6,11-dienoyl]-2-aminohexacosa-11,20-diene-1,3,4,5-tetrol (2) were isolated from the ethyl acetate fraction obtained from the methanol extract of the stem barks of Cassia arereh together with seven known compounds. Their structures were characterized using two-dimensional NMR, mass spectrometry, and compared with reported data. To date, this is the first report of the isolation of a multiple double bonds sphingolipid type (2) from this genus. The ethyl acetate extract and selected isolates were examined for antimicrobial and cytotoxic activities in vitro. Betulinaldehyde (5) has shown to be active against all bacterial strains whereas, cassiaric acid (1) and betulinic acid (6) have demonstrated to be moderately active. In addition, cassiaric acid (1) showed the best cytotoxic result against HeLa and MCF-7 cell lines tested with IC50 75.00 µM, while lupeol (3) and betulinic acid (6) displayed weak cytotoxicity at 100.00 µM.

In vitro antitubercular activity of extract and constituents from the stem bark of Disthemonanthus benthamianus

ABSTRACT A new C-glycosylflavone, apigenin 7-methyl ether 6-C-[β-xylopyranosyl-(1→3)-β-glucopyranoside] named distemonanthoside was isolated from the stem bark of Distemonanthus benthamianus Baill., Fabaceae, along with six known compounds, sitosterol 3-O-β-D-glucopyranoside, 4-methoxygallic acid, syringic acid, quercetin, 6"-O-acetylvitexin, quercetin 3-O-β-D-glucopyranoside. The structures of those compounds and others were determined through spectral analyses. Compounds distemonanthoside, sitosterol 3-O-β-D-glucopyranoside, 4-methoxygallic acid and quercetin were tested against a clinical isolate strain of Mycobacterium tuberculosis AC 45; they exhibited good to moderate antitubercular activities with MIC values ranged from 31.25 to 125 µg/ml.