A study on the nitric oxide production-suppressing activity of Sanguisorbae Radix components

The active components of an aqueous extract of Sanguisorbae Radix, which po ssesses nitric oxide (NO) production-suppressing activity, were determined using macrophages that were activated by the addition of lipopolysaccharide , Significant inhibitory activity against the formation of both NO and indu cible NO synthase, and NADPH-diaphorase activity, which is involved in NO g eneration, was shown by Sanguisorbae Radix fractions T-B and T-C, On furthe r fractionation, the subfractions of T-B and T-C all showed high anti-NO ac tivity. Sanguiin H-6, sanguiin H-11, 1,2,3,4,6-penta-0-galloyl-beta-D-gluco se, eugeniin and polymeric proanthocyanidin were isolated from TB-3 and TC- 4, and all were identified as exhibiting strong anti-NO activity. We have c onfirmed that sanguiin H-6 is the most active component of Sanguisorbae Rad ix with respect to the suppression of NO production. It is suggested that t annin makes a prominent contribution to the biological activity of Sanguiso rbae Radix.