Two new antiinflammatory triterpene saponins from the Egyptian medicinal food black cumin (seeds of Nigella sativa)

Abstract

An extensive phytochemical investigation of the polar fractions of a methanolic extract of Egyptian medicinal food, black cumin (seeds of Nigella sativa L.) led to the isolation of two new triterpene saponins, named sativosides A and B (1-2), along with four known saponins (3-6). Sativoside A (1) is the first example of saponins containing 18-ene triterpene aglycon not only in this Nigella genus but also in the family Ranunculaceae. The structure of the new saponins was elucidated mainly by a combination of 1D and 2D NMR data, together with HRFABMS and acid hydrolysis. Three compounds (1-3) showed the significant inhibition effect of phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-induced production of IL-6 in a human mast cell (HMC-1) line.