title: Bioactive saponins from Astragalus suberi L. growing in Yemen.
abstract: From the aerial parts of Astragalus suberi L., Fabaceae, seven saponins were isolated. Based on spectral data (IR, 1H and 13C NMR and HR-FABMS), the structures were established as 3-O-(beta-D-glucopyranosyl)-soyasapogenol B (1); 3-O-(beta-D-glucuronopyranosyl)-soyasapogenol B (2); 3-O-[beta-D-galactopyranosyl (1-->2)-beta-D-glucopyranosyl]-soyasapogenol B (3); 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-galactopyranosyl (1-->2)-beta-D-glucopyranosyl]-soyasapogenol B (4); 3-O-[beta-L-rhamnopyranosyl (1-->2)-beta-D-galactopyranosyl (1-->2)-beta-D-glucopyranosyl]-11-hydroxy-soyasapogenol B (5); 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-galactopyranosyl (1-->2)-beta-D-glucuronopyranosyl]-soyasapogenol B (6) and 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-galactopyranosyl (1-->2)-beta-D-glucuronopyranosyl]-complogenin (7). The isolated saponins exhibited antibacterial activities against Gram-positive and Gram-negative bacteria with minimum inhibitory concentration values >100 microg/ml, antifungal activity against all the strains tested with minimum fungicidal concentration values between 25 and 50 microg/ml and inhibited the growth of Hep-2 (human carcinoma of larynx), with IC50 values between 50 microg/ml (compounds 5-7) and 100 microg/ml (compounds 1-4), and Hela (human carcinoma of cervix) cell lines in culture with different IC50 values [74 (compound 7), 98 (compound 5) and 180 microg/ml (compounds 1-4 and 6)].
authors.affiliation: Department of Pharmacology, Faculty of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Fawkeya
authors.initials: F
authors.lastname: Abbas
authors.forename: Rawia
authors.initials: R
authors.lastname: Zayed
mesh_terms: D002240:Carbohydrate Sequence; D007887:Fabaceae / Q000737:chemistry*; D008279:Magnetic Resonance Imaging; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry / Q000302:isolation & purification; D012503:Saponins / Q000737:chemistry* / Q000302:isolation & purification*; D015006:Yemen
chemical_list: D009844:Oligosaccharides; D012503:Saponins