RESUMO
Aim To study the anti-HBV effect of alcohol extract from styela plicata Lesueur,styela canopus Savigny and symplegma oceania Tokioka in vitro and estimate their function.Methods An assay system based on the sera of HBV infection and HBV clearance was used to assess their inhibitory effects on HBsAg,HBeAg,anti-HBs and anti-HBe.Results Alcohol extract from the three species of ascidians all had a definite inhibition effect on HBsAg when the concentration was over 2 g?L -1 and a favorable inhibition effect on HBeAg when the concentration was over 0.5 g?L -1.There was no significant difference in inhibiting the two kinds of antigen.Conclusion Alcohol extract from the three species of ascidians all had the definite inhibition effects on HBsAg and HBeAg from serum of Hepatitis B patients.The inhibition effects were dose-dependent. From the effcets of alcohol extract on anti-HBs and anti-HBe,we can estimate that there are about two kinds of anti-HBV compositions.One has the similar structure with the antibody,which can exterminate the HBV by the way of forming a uninfectious combination with the antigen. The other has a definite inhibition effect on the antigen,and also has some inhibition effect on the antibody.