No abstract

The barks of two subspecies of BERSAMA ABYSSINICA, subspecies ABYSSINICA and subspecies PAULLINIOIDES have been shown to contain two bufadienolides: 5beta, 14beta-dihydroxy-3,6-diacetoxy-Delta (6)-bufa-20,22-trienolide ( 1) and 3-acetoxy-14beta-hydroxy-bufa-20,22-dienolide ( 2). Three sterols : beta-sitosterol, Delta (4)-stigmasten-3alpha-ol ( 3) and 4-methyl-Delta (5,23)-stigmast-dien-3beta-ol ( 4) have also been isolated. 3 is a new compound and 3 and 4 are reported for the first time from the Melianthaceae. The presence of the xanthone mangiferin is a possible taxonomic marker for the genus within this family. Differences between the two subspecies were seen on examining the glycoside fractions. The alcoholic extracts did not exhibit any anti-tumour activity in the standard test.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Melting points were determined by means of a Kofler hot plate and are uncorrected. UV spectra were determined in MeOH, IR in KBr discs, 'H-NMR were recorded in CDCI3 on a Brucker 270 MHz, tetramethylsilane was used as internal standard and MS were obtained at 70 eV. All the compounds were identified by spectroscopical properties and, with the exception of byankangelicin, were compared with authentic samples.

S RB cytotoxicity assay was performed for different extracts of Hamelia patens Jacq. family Rubiaceae; crude flowers (CF), crude leaves (CL), chloroform (Chl.L) and methanol (Me.L) fractions from leaves against liver (HepG-2) and breast (MCF-7) human carcinoma cell lines. Results demonstrated potent cytotoxic action against HEPG-2 for CF, Chl.L and Me.L with IC 50 = 47, 30 and 44.4 µg/mL, respectively. On the other hand, CF, CL, Chl.L and Me.L had exerted powerful effect against MCF-7 with IC 50 = 23.8, 25.5, 17.7 and 64 µg/mL, respectively. Chromatographic investigation of Me.L , resulted in the isolation and spectroscopic identification of rutin (1), isoquercetin (2) and soyasaponin Bb (3), which was isolated for the first time from the plant leaves and was identified by UPLC/ITMS/MS analysis. Comparative study for using ordinary method versus green methods of extraction was also inspected.