安石榴苷和绿原酸对金黄色葡萄球菌的协同抑制作用及机理研究

李光辉; 郭卫芸; 高雪丽; 王永辉; 孙思胜; 夏效东

doi:10.13386/j.issn1002-0306.2018.10.004

安石榴苷和绿原酸对金黄色葡萄球菌的协同抑制作用及机理研究

Synergistic antimicrobial effect and mechanism of punicalagin and chlorogenic acid against Staphyloccocus aureus

摘要

摘要: 研究安石榴苷和绿原酸对金黄色葡萄球菌的协同抑菌作用及机理,为开发控制金黄色葡萄球菌的新型食品防腐剂提供理论基础。利用"棋盘法"研究安石榴苷和绿原酸对金黄色葡萄球菌的协同抑制作用;通过观察安石榴苷和绿原酸单独作用及协同作用对生长曲线、细胞膜电势、胞内外pH差及细胞形态等影响来探究协同抑菌机理。结果为安石榴苷和绿原酸对金黄色葡萄球菌具有协同抑制作用;与1/4最小抑菌浓度(MIC)安石榴苷或1/16 MIC绿原酸单独作用相比,在1/4 MIC安石榴苷和1/16 MIC绿原酸协同作用下,金黄色葡萄球菌的生长受到抑制,细胞膜发生去极化现象,胞内外pH差发生改变,细胞膜破损,菌体解体。协同作用组的膜电势、胞内外pH差分别与对照组有显著差异(p<0.05)。结果表明,安石榴苷和绿原酸的协同抑菌机理主要是二者协同破坏细胞膜,致使细胞膜破损,从而影响细菌的正常生长和繁殖。

Abstract: The aim of the study was to explore the synergistic antimicrobial effect of punicalagin and chlorogenic acid against Staphyloccocus aureus and to elucidate its mechanism. The checkerboard microtiter tests were used. The growth curve, intracellular pH (pH_in) and membrane potential were measured to illustrate the antibacterial mechanism. Morphological changes induced by punicalagin and chlorogenic acid were examined by electron microscopy. The results showed that compared with 1/4 MIC punicalagin or 1/16 MIC chlorogenic acid, the combination of punicalagin and chlorogenic acid displayed strong synergistic antibacterial effect against Staphyloccocus aureus, resulting a notable reduction in (pH_in-pH_out), cell membrane depolarization andmembrane disruption. There was a noteworthy difference in membrane potential or (pH_in-pH_out) between the combined group and the control group. In conclusion, there was a notable synergistic antimicrobial effect of punicalagin and chlorogenic acid against Staphyloccocus aureus, which can be achieved by destroying the cell membrane integrity.