激光扫描共聚焦显微镜观察碱性环境对粪肠球菌生物膜的影响

Confocal laser scanning microscopic observation of Enterococcus faecalis biofilm under alkaline stress

目的:比较不同碱性条件对生物膜状态粪肠球菌的影响。方法:制备粪肠球菌生物膜,分别用pH值为7、9和11的TSB培养液作用2 h后,用激光扫描共聚焦显微镜观察粪肠球菌生物膜的变化。结果:pH值由7升到9时,生物膜内、中、外各层活菌比例虽有所减少,但差异无统计学意义(P>0.05);当pH值11时,各层活菌比例虽然均较pH值为7和9时明显减少(P<0.05),但仍有大量活菌存在。结论:粪肠球菌对碱性环境具有强的耐受性,pH值为7～9时,对生物膜状态粪肠球菌无明显影响。

AIM ： To observe the changes of the architecture of Enterococcus faecalis （ E. Faecalis） biofilms under different alkaline conditions by confocal laser scanning microscopy （CLSM）. METHODS ： E. faecalis was pre- pared in biofilm mode on coverslips and cultured in TSB mediums at pH 7, 9 and 11 for 2 hours respectively. The scanning picture, depth and the area of green and red light per layer of biofilms were observed by CLSM. Bacterial density and the percentage of vital bacteria were calculated. RESULTS ： It was shown that a lot of vital and dead bac- teria gathered densely in biofilms. E. faecalis biofilm had different three-dimensional spatial architecture under diverse pH conditions. CONCLUSION： Biofilm mode of E. Faecalis has high alkaline tolerance.