苦楝素联合BIT对白色念珠菌的协同抑菌效果研究

Synergistic antibacterial effects of toosendanin combined with BIT on Canidia albicans

探讨苦楝素与BIT分别单独及二者联合使用对白色念珠菌的浮游菌生长及其生物膜形成的影响。以预加菌液倾注平板打孔抑菌实验法测定苦楝素、BIT及二者联合使用对白色念珠菌菌体生长的抑制效果,96孔板微量稀释法培养该菌浮游菌及其生物膜,分别测定浮游菌及其生物膜的吸光度并进行比较分析,判断最小抑菌浓度(MIC),计算二者联合时的抑菌指数(FIC)。平板打孔抑菌实验结果显示,其抑菌效果依次为:二者联合>BIT>苦楝素;96孔微量稀释法结果显示:二者联合的FIC系数为0.75;二者联合抑制该浮游菌生长比单用时药效增加了20%~50%,抑制其生物膜的形成比单用时药效增加了33%~50%。苦楝素与BIT联合使用具有对白色念珠菌生长的复配增效抑制作用,不但有效抑制该菌浮游菌生长,也能抑制其生物膜的形成。

The effects of toosendanin alone or BIT alone and their combinations on planktonic growth and biofilm formation of Candida albicans were investigated respectively.The susceptibility of toosendanin,BIT and their combinations to Candida albicans were determined by pre-incubation bacterial suspensions in the plates.The planktonic cells and biofilms were firstly cultured in the 96-well plates,and then their optical density(OD)values at 600 and 595 nm were determined and compared,respectively.Minimum inhibitory concentration(MIC)was also detected to calculate the fractional inhibitory concentration(FIC).The antibacterial effects of plate punching showed that the antibacterial efficiency were as follows:combinations>BIT>toosendanin;96-well micro-dilution method demonstrated that the FIC coefficient of the combinations was 0.75;the combined inhibition effects of the planktonic bacteria and biofilm formation increased by 20%to 50%and 33%to 50%,compared with the single use,respectively.As a result,the combination of toosendanin with BIT exhibited the synergistic inhibitory effects on Candida albicans,which not only effectively inhibited the growth of the planktonic cells,but also inhibited the formation of its biofilm.