New principles from seeds of Nigella sativa.

A new triterpene saponin and known steroidal glucoside were isolated from the alcohol extract, and a new cycloartenol from n-hexane extract of seeds of Nigella sativa L. and were identified as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl]-11-methoxy-16,23-dihydroxy-28-methylolean-12-enoate (1), stigma-5,22-dien-3-beta-D-glucopyranoside (2) and cycloart-23-methyl-7,20, 22-triene-3beta,25-diol (3), respectively. They were characterised on the basis of spectral analysis and comparison with literature data. The hexane and alcohol extract of the seeds showed antimicrobial activity. The antioxidant activity of hexane extract is also described.