The anti-endotoxic effect of o-aminobenzoic acid from Radix Isatidis

Abstract

Aim: To study the anti-endotoxic effect of o-aminobenzoic acid (OABA) isolated from Banlangen(BLG). Methods: OABA was extracted and isolated from BLG and diluted into 0.5% solution. The concentration of endotoxin (ET) pretreated with OABA was quantitatively detected using Limulus test. The inhibition of ET-induced fever by OABA was measured in rabbits. The rates of lipopolysaccharides (LPS)-induced death in mice pretreated with or without OABA were then compared. The influence of OABA on the release of TNF-α and NO from macrophages induced by LPS was examined in mice. Results: After pretreatment with OABA, 84.4% of ET was destroyed. The ET-induced fever in rabbits decreased significantly and the rate of LPS-induced death in mice dropped from 70% to 20%. The release of TNF-α and NO induced by LPS in mice was inhibited dose-dependently when the concentration of OABA was between 0.125% and 0.5%. Conclusion: OABA isolated from BLG has an anti-endotoxic effect. ©2005 CPS and SIMM.