摘要
目的:以大肠杆菌和金黄色葡萄球菌为研究对象,探讨胡桃醌对微生物不同阶段生长及形态特征的影响,为胡桃醌抑菌机理的研究奠定基础。方法:采用紫外分光光度计和平板计数法绘制生长曲线,通过透射电镜观察菌体形态特征的变化。结果:大肠杆菌的迟缓期和对数期受到胡桃醌的抑制作用明显;处于对数期的金黄色葡萄球菌对胡桃醌的抑制作用更为敏感。透射电镜的结果表明,最低抑菌浓度下的胡桃醌作用大肠杆菌2h,菌体即出现细胞质壁分离现象,细胞质分布不均匀;8h后,细胞壁破坏严重,内溶物流出。胡桃醌作用金黄色葡萄球菌4h,菌体细胞吸水膨胀,部分细胞隔膜已被破坏。8h后,菌体互相粘连,细胞与细胞间的界限变得模糊。结论:胡桃醌的抑菌效果主要表现在细菌生长的对数期,并可能通过破坏菌体的细胞壁或细胞膜结构来抑制细菌的生长。
Objective.The effect of juglone on S.aureaus and E cofi growth in different stages and morphological characteristics were studied, so as to discover the antibacterial mechanism of juglone. Method： The UV spectrophotometer and enumeration platecount method were used to determine cell growth curves.Observations of bacteria morphological characteristics were conducted by Transmission electron microscopy （TEX）. Result： The result showed that the growth of E.cofi in lag phase and log phase were obviously influenced by juglone.While for S.aureaus,its growth in log phase was more sensitive to juglone.Result from observation by TEX showed that the cytoplasm was concentrated and the cell was plasmolysed 2 hours after adding juglone to cultivative medium at minimum inhibition concentration（ MIC） .The cell wall was damaged seriously and the contents were leaked out after 8 hours.While for S.aureus,the cells absorbed water to expand,and part of the cell membrane was destroyed 4 hours after adding juglone to cultivative medium at MIC.Eight hours later, bacterial were adherent and boundaries tended to be illegible. Conclusion-It was suggested that juglone might influence bacterial growth at logarithmic stage.Also, it might inhibit growth of bacteria through damaging cell wall or cell membrane,
出处
《食品工业科技》
CAS
CSCD
北大核心
2012年第6期131-134,共4页
Science and Technology of Food Industry
基金
辽宁省科学技术基金项目(20102195)
