柠檬草精油对副溶血性弧菌的抑菌活性及机制  

Antibacterial Activity and Mechanism of Lemon Grass Essential Oil(LG-EO)on Vibrio parahaemolyticus

作　　者：孙杨 王晓迪 朱军莉 陆海霞 倪勤学[2] Sun Yang;Wang Xiaodi;Zhu Junli;Lu Haixia;Ni Qinxue(School of Food and Bioengineering,Zhejiang Gongshang University,Key Laboratory of Food Safety of Zhejiang Province,Hangzhou 310018;College of Agriculture and Food Science,Zhejiang Agricultural and Forestry University,Linan 311300,Zhejiang)

机构地区：[1]浙江工商大学食品与生物工程学院浙江省食品安全重点实验室,杭州310018 [2]浙江农林大学农业与食品科学学院,浙江临安311300

出　　处：《中国食品学报》2023年第3期157-167,共11页Journal of Chinese Institute Of Food Science and Technology

基　　金：浙江省基础公益研究计划项目(LGF19C200003,LGN20C200007,LGN22C200025)。

摘　　要：目的:探究柠檬草精油(LG-EO)对副溶血性弧菌的抑菌活性和机理。方法:通过测定LG-EO对副溶血性弧菌的最低抑制浓度(MIC)、时间-杀灭分析、上清液中AKP活性、电导率和蛋白质泄漏量、细胞形态、膜电位、呼吸链脱氢酶活力及胞内DNA的含量和结构等,研究LG-EO对副溶血性弧菌的抑菌活性和机制。结果:LG-EO对副溶血性弧菌的MIC范围80~120μg/mL,在80~280μg/mL处理浓度范围,其杀灭效果随浓度和时间的增加而提高,240μg/mL LG-EO处理10 min即可灭活全部副溶血弧菌。与高于MIC的LG-EO共培养,副溶血弧菌细胞壁、膜的完整性被破坏,导致上清液中AKP活性、蛋白质含量和电导率上升,细胞边界模糊和内容物流失。菌体细胞膜电位、呼吸链脱氢酶和ATP酶活性等显著降低。基因组DNA的核酸电泳和紫外吸收光谱提示,DNA在LG-EO作用下流失严重并与主要成分柠檬醛发生互作。结论:柠檬草精油对副溶血性弧菌有较强的抑菌作用,LG-EO通过破坏细胞壁、膜构造,干扰细胞能量代谢,造成DNA流失或变性等快速杀灭副溶血性弧菌。本研究为探明LG-EO的抑制致病性弧菌机理奠定良好的基础,在水产品加工业中具有广泛的应用潜力。Objective:This study aimed to uncover antimicrobial activity and mechanism of LG-EO on Vibrio parahaemolyticus(VP).Methods:The antimicrobial activity and possible mechanism of LG-EO on VP were investigated through MIC(minimum inhibitory concentration),time-kill assay,AKP(alkaline phosphatase)activity in supernatant,leakage of electrical conductivity(EC)and protein,cells morphology,membrane potential,respiratory chain dehydrogenase activity and intracellular DNA content and structure.Results:The MIC of LG-EO against three VP strains was about 80μg/mL to 120μg/mL,and the killing efficacy enhanced with increasing concentration at 80-280μg/mL and extension of treated time.Treatment with 240μg/mL LG-EO for 10 min resulted in no viable bacterial count of all three VP strains(detection limit 1lg CFU/mL).Treated with LG-EO above MIC,the integrity of the cell wall and membrane was disrupted,leading to a rise in AKP activity,protein content and conductivity in the supernatant and changes in cellular ultrastructure.In the VP strains treated LG-EO,cell membrane potential reduced,and activities of respiratory chain dehydrogenases and ATPases decreased,indicating the energy metabolism of VP was interrupted.Moreover,LG-EO could interact with bacterial DNA via intercalation,to disturb the normal cellular functions.Conclusion:LG-EO showed strong antimicrobial effect against VP by disrupting cell wall and membrane,interfering with cellular energy metabolism,causing DNA loss or denaturation.Thus,LG-EO is expected to be an alternative for novel multifunctional food additive with bacteriostatic action in aquatic food industries.

关 键 词：副溶血弧菌 柠檬草精油 抑菌机理 细胞通透性 能量代谢 DNA损伤 

分 类 号：TS201.3[轻工技术与工程—食品科学]