Antibacterial effect of 100 Chinese herbal medicines against Vibrio alginolyticus in vitro

The inhibitory effects of 100 Chinese herbal medicines on Vibrio alginolyticus were tested with disc diffusion method and 24 herbs showed the antibacteria effects.However,the antibacterial effect dropped down very significantly(p0.01) when the extract solution pH values of the herbs were regulated to about 7.0 from acid primary medicine solutions.The tube dilution method was used to measure the minimal inhibitory concentration(MIC) and minimal bactericidal concentration(MBC) of seven Chinese herbal medicines which were able to inhibit the growth of V.alginolyticus.The results showed that Rhus chinensis,Flos caryophylli and Punica granatum had inhibitory and bactericidal effects against V.alginolyticus when the extract solution pH values were regulated to approximate 7.0,and the MIC and MBC were 7.813 mg/mL for R.chinensis,15.625 mg/mL for P.granatum,125 mg/mL for F.caryophylli,500 mg/mL for Coptis chinensis,Polygonatum sibiricum and Rheum officinale,and 1 000 mg/mL for Schisandra chinensis,respectively.