부산대학교 도서관

During our studies on search for bioactive natural products, we recently examined extracts of several medicinal plants collected in north-east parts (Khon Kaen area) of Thailands, and the methanolic extracts from the leaves of Agave fourcroydes (Agavaceae) and the stems of Calamus insignis (Palmae) were found to have cell growth inhibitory activity against HeLa cells. In this paper, we describe the isolation, structure determination of steroidal saponins from A. fourcroydes and C. insignis, and their anti-tumor activity (cell growth inhibitory activity and cell cycle inhibitory activity). From the leaves of Agave fourcroydes and the stems of Calamus insignis, 10 steriodal saponins (1-10) were isolated and their structures were determined by several spectral data and acid hydrolysis. Among them, 3, 7, 8, 9, and 10 were new compounds. Isolated steroidal saponins, except for 2, 4, and 9, showed cell growth inhibitory activity against HeLa cells at low concentration (IC_<50> value: <10μM). Effects of 6, 7, and 8 on the cell cycle progression of HeLa cells were also investigated to reveal that 6 and 8 arrested the cell cycle at the G2/M phase at the concentration of 1.5 and 2.9μM. It was suggested that this effect of 6 resulted from expression of p21 and inhibition of dephosphorylation of cdc2.