Studies On The Constituents Of Scutellaria Barbata Anti-tumor Activity

Scutellaria barbata D. Don,a herb belonging to the Lamiaceae family, is widely distributed in China. This herb is known in traditional Chinese Medicine as Ban-Zhi-Lian and has been used as an anti-inflammatory and antitumor agent and as a diuretic. However, active constituents and the mechanism underlying the activity were unclear. In this study, we used the bioassayed-guided fractionation of Scutellaria barbata to find active fractions for antitumor and then try to elucidate active constituents.In order to find out active constituents for antitumor, we have studied active fractionation of Scutellaria barbata. Ethanolic extract of Scutellaria barbata was dissolved in water and fractionated sequentially with n-hexane, chloroform, ethylacetate and n-butanol. The fractions were concentrated under reduced pressure to yield a Petroleum ether fraction, chloroform fraction, ethylacetate fraction, n-butanol fraction and remainder of water fraction. Antitumor activity of each fraction was evaluated by the MTT assay using human cancer cell lines. chloroform fraction showed the greatest antitumor activity in vitro.Petroleum ether fraction, chloroform fraction, ethylacetate fraction were separated by chromatographed on silica gel, Sephadex LH-20 to yield six monomers. Scuterivulactone C1(Ⅰ), 5,7,4' -trihydroxy-8-methyl flavone and 5, 7, 8, 4' -tetrahydroxy flavone(Ⅱ) and( Ⅲ )were isolated from chloroform fraction; 5, 7-dihydroxy-4' -methoxy flavone (Ⅳ) was isolated from ethylacetate fraction; β-sitostreols (Ⅴ), phytol (Ⅵ) were isolated from Petroleum ether fraction. Three compounds showed significant cytotoxic effect to Bel-7402 cell lines.