1 Laboratory of Food Microbiology, College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China (ORCID: https://orcid.org/0000-0003-4483-1386 [Q.Z.]).
2 Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou, Jiangsu 225009, People's Republic of China.
J Food Prot. 2019 May;82(5):826-833. doi: 10.4315/0362-028X.JFP-18-418.
This study investigated the antimicrobial mechanism of phytic acid (PA) and its antibacterial effects in combination with ethanol. The MIC of PA on ATCC 11229, ATCC 6538P, ATCC 6633, and Typhimurium CICC 27483 were 0.24, 0.20, 0.26, and 0.28% (w/w), respectively. ATCC 11229 and ATCC 6538P were selected to investigate the mechanism of PA by analyzing its effects at 1/2MIC and at MIC on the cell morphology, intracellular ATP, and cell membrane integrity. Environmental scanning electron microscope images revealed that PA was able to change the cell morphology and disrupt the intercellular adhesion. PA retarded bacterial growth and caused cell membrane dysfunction, which was accompanied by decreased intracellular ATP concentrations. Flow cytometry analysis further revealed that almost all the bacterial cells were damaged after treatment with PA at its MIC for 2 h. Moreover, PA has a synergistic antimicrobial ability when used in combination with ethanol. These results suggested that PA is effective in inhibiting growth of foodborne pathogens mainly by the mechanism of cell membrane damage and to provide a theoretical basis for the development of natural antimicrobial agents in the food industry.
本研究探讨了植酸（PA）的抗菌机制及其与乙醇联合的抗菌效果。PA 对 ATCC 11229、ATCC 6538P、ATCC 6633 和 鼠伤寒 CICC 27483 的 MIC 分别为 0.24%、0.20%、0.26%和 0.28%（w/w）。选择 ATCC 11229 和 ATCC 6538P 来研究 PA 的作用机制，通过分析其在 1/2MIC 和 MIC 下对细胞形态、细胞内 ATP 和细胞膜完整性的影响。环境扫描电子显微镜图像显示，PA 能够改变细胞形态并破坏细胞间的黏附。PA 抑制细菌生长并导致细胞膜功能障碍，伴随着细胞内 ATP 浓度降低。流式细胞术分析进一步表明，在用 PA 在 MIC 下处理 2 小时后，几乎所有的细菌细胞都受到了损伤。此外，PA 与乙醇联合使用具有协同抗菌能力。这些结果表明，PA 通过破坏细胞膜的机制有效抑制食源性致病菌的生长，为食品工业中天然抗菌剂的开发提供了理论依据。
