Cytotoxic, anti-inflammatory and hemostatic spirostane-steroidal saponins from the ethanol extract of the roots of Bletilla striata.

Four new spirostane steroidal saponins, (1α,3α)-1-O-[(β-d-xylopyranosyl-(1→2)-α-l-rhamnopyranosyl)]-3-O-d-glucopyranosyl-5α-spirostan (1), (1α,3α)-1-O-[(β-d-xylopyranosyl-(1→2)-α-l-rhamnopyranosyl)oxy]-3-O-d-glucopyranosyl-25(27)-ene-5α-spirostan (2), (1α,3α)-1-O-[(β-d-xylopyranosyl-(1→2)-α-l-rhamnopyranosyl)oxy]-epiruscogenin (3), and (1α,3α)-1-O-[(β-d-xylopyranosyl-(1→2)-α-l-rhamnopyranosyl)oxy]-epineoruscogenin (4) together with two known compounds, bletilnoside A (5) and 3-O-β-d-glucopyranosyl-3-epi-neoruscogenin (6), were isolated from the ethanol extract of the roots of Bletilla striata (Thunb.) Reichb. f. The structures of the isolated compounds were established based on 1D and 2D ((1)H-(1)H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated compounds were tested in vitro for cytotoxicities against seven tumor cell lines, anti-inflammatory activities against Cox-1 and Cox-2, and hemostatic activities. As a result, compounds 1-4 and 6 exhibited significant cytotoxicities against all the tested tumor cell lines with IC50 value less than 30μM and selective inhibition of Cox-2 comparable with the standard drug NS-398 (>90%). Additionally, compounds 1-6 showed potent hemostatic activities.