亚甲基蓝对大肠杆菌O157的光动力杀伤作用及机理  

Mechanisms of Anti-microbial Photodynamic Technology Against Escherichia coli O157 by Methylene Blue

作　　者：唐姝姝[1] 唐书泽[1] 李红爱[1] 吴希阳[1] 陈振强[2] 

机构地区：[1]暨南大学食品科学与工程系,广东广州510632 [2]暨南大学光电工程系,广东广州510632

出　　处：《食品与发酵工业》2012年第7期68-72,共5页Food and Fermentation Industries

基　　金：暨南大学科研培育与创新基金项目

摘　　要：探讨亚甲基蓝对革兰氏阴性菌肠出血性大肠杆菌O157的光动力杀伤作用及机理。通过细菌平板菌落计数法研究亚甲基蓝对肠出血性大肠杆菌O157的光动力杀伤作用,同时运用实时荧光定量PCR技术和聚丙烯酰胺凝胶电泳观察光动力技术对O157的基因组DNA的损伤程度和蛋白质降解效果。结果表明,当亚甲基蓝的浓度为10 mg/L,可见光(光功密度为200 mW/cm2)光照30 min时,几乎全部的肠出血性大肠杆菌O157能被杀死,并伴随有DNA断裂和蛋白质降解。亚甲基蓝对革兰氏阴性菌肠出血性大肠杆菌O157有非常明显的光灭活效应,其灭活机理可能是对基因组DNA的损伤以及蛋白质的降解。The mechanisms of anti-microbial photodynamic technology（APDT） against Gram-negative bacteria Escherichia coli O157 by methylene blue （MB） was investigated. The bactericidal effect of MB-APDT on E. coli O157 was measured by counting the reduction of colony forming unit（CFU）. The damage of DNA was observed by real-time polymerase chain reaction （RT-PCR） and the degradation of proteins was investigated by sodium dodecyl sulphate polyacrylamide gel electrophoresis （SDS-PAGE）. Results showed that almost all of the E. coli O157 were photo inactivated by illumination with 30 min visible light （power density 200 mW/cm2） in the presence of 10 mg/L MB. The significant photo-inactivation of Gram-negative bacteria Escherichia coli O157 may be due to the damage of DNAs and the degradation of proteins.

关 键 词：亚甲基蓝 肠出血性大肠杆菌O157 光动力灭菌技术 脱氧核糖核酸损伤 蛋白质降解 

分 类 号：TS201.3[轻工技术与工程—食品科学]