Investigation of the effect of berberines alkaloids in Coptis chinensis Franch on Bacillus shigae growthby microcalorimetry

摘要

The inhibitory effects of five berberines alkaloids (BAs) from rhizoma of Coptis chinensis Franch,a traditional Chinese medicinal (TCM) herb,on Bacillus shigae(B.shigae) growth were investigated by microcalorimetry.The power-time curves of B.shigae with and without BAs were acquired;meanwhile,the extent and duration of inhibitory effects on the metabolism were evaluated by growth rate constants (k1,k2),half inhibitory ratio (IC50),maximum heat output (P_(max)),and peak time (t_p).The values of k1 and k2 of a shigae in the presence of the five BAs decreased with the increasing concentrations of BAs.Moreover,P_(max) was reduced,and the value of t_p increased with increasing concentrations of the five drugs.The inhibitory activity varied with different drugs.IC50 of the five BAs was respectively 75 mu g/mL for berberine,90 ng/mL for coptisine,115 mu g/mL for palmatine,220 mu g/mL for epiberberine,and 400 mu g/mL for jatrorrhizine.The sequence of antimicrobial activity of the five BAs:berberine > coptisine > palmatine > epiberberine > jatrorrhizine.The functional groups methylenedioxy at C2 and C3 on phenyl ring improve antimicrobial activity more strongly than methoxyl at C2 and C3 on phenyl ring.However,the effect of bacteriostasis is not significant with methylenedioxy or methoxyl at C9 and C10 on phenyl ring.