碱性环境对饥饿期粪肠球菌疏水性的影响  

Influence of alkaline environment on the hydrophobicity of starved Enterococcus faecalis

作　　者：卢婷[1] 徐琼[1] 

机构地区：[1]中山大学光华口腔医学院.附属口腔医院//广东省口腔医学重点实验室,广东广州510055

出　　处：《南方医科大学学报》2012年第5期681-684,共4页Journal of Southern Medical University

基　　金：广东省科技计划项目(2009B030801115;2010B050700007)

摘　　要：目的研究碱性环境对饥饿期粪肠球菌表面疏水性的影响,了解氢氧化钙影响细菌粘附的机制。方法收集饥饿期粪肠球菌,在pH值为7.3、8.3、9.3、10.3的氢氧化钙溶液中分别孵育15 min和1 h,采用微生物粘着碳氢化合物法(MATH)检测细菌表面疏水率;扫描电镜观测不同pH值的碱性环境中粪肠球菌对人牙本质片粘附量的变化。结果随着氢氧化钙溶液pH值上升,饥饿期粪肠球菌表面疏水率逐渐升高(P<0.01);相同pH值条件下,1 h细菌表面的疏水率高于15 min(P<0.05);电镜下细菌对牙本质粘附量随溶液pH值上升而增多。结论碱性环境可提高饥饿期粪肠球菌表面疏水性,促进细菌初始粘附。Objective To study the effect of calcium hydroxide solutions at different pH values on the cell-surface hydrophobicity of starved Enterococcus faecalis.Methods E.faecalis in starvation were harvested and incubated in freshly prepared calcium hydroxide solutions at the pH values ranging from 7.3 to 10.3 for 15 min or 60 min.The cell-surface hydrophobicity of the starved E.faecalis was evaluated by measuring microbial adhesion to hydrocarbons（MATH）.Scanning electron microscopy was used to investigate the adhesion capability of starved E.faecalis cells incubated on human dentin at different pH levels.Results For the same duration of treatment,increased pH value of calcium hydroxide solution significantly enhanced the cell-surface hydrophobicity of starved E.faecalis（P0.01）.At the same pH value,the cell-surface hydrophobicity of the bacterium increased significantly with time（P0.05,15 min vs 60 min）.Scanning electron microscopy revealed a significantly increased adhesion of the starved cells on human dentin as the pH value and incubation time increased.Conclusion Calcium hydroxide solutions promote the adhesion of starved E.faecalis by modifying its cell-surface hydrophobicity.

关 键 词：肠球菌 粪 饥饿 疏水性 氢氧化钙 碱性环境 粘附 

分 类 号：R781.05[医药卫生—口腔医学]