为了开发更安全有效的榨菜用保鲜剂，需要测试山梨酸钾（PS）和Nα-月桂酰-L-精氨酸乙酯盐酸盐（LAE）以及其复配的抑菌性和应用效果，并探索其机理。本研究从腐烂榨菜分离出致腐菌作为研究对象，应用棋盘格法体外抑菌实验测试了不同pH环境下，LAE和PS对其最小抑菌浓度（MIC），以及测试了两者联合抑菌作用，并在榨菜保鲜中验证了效果。此外以分离出的最主要致腐菌为研究对象，对LAE胁迫下其过氧化物酶（POD）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）活性、DPPH自由基清除率、蛋白质含量、丙二醛（MDA）含量进行了测定。分离得到主要致腐菌：盐脱氮枝芽胞杆菌（Virgibacillus halodenitrificans），施氏假单胞菌（Pseudomonas stutzeri）和微紫青霉菌（Penicillium janthinellum）作为被试菌，结果显示LAE对其MIC为16~32 mg/L，PS对其MIC为256~1024 mg/L，PS表现出抑菌强度和酸度正相关，LAE则相反。PS和LAE对被试菌株表现出加合或协同联合抑菌作用。在袋装榨菜中LAE和PS复配使用能够抑制微生物增殖达1~2个数量级。在LAE胁迫下，细菌POD、CAT、SOD活性上升，DPPH自由基清除率、蛋白质和MDA含量下降。LAE和PS能够有效抑制榨菜中的致腐菌，并且拥有复配提效的潜力。此外，LAE潜在的抑菌机理可解释为其使微生物细胞膜完整性降低、氧化应激水平升高。

In order to develop a safer and more effective preservative for pickled mustard tubers, it is necessary to examine the antimicrobial activities, applications and underlying mechanisms of potassium sorbate (PS) and N-α-lauroyl-L-arginine ethyl ester monohydrochloride (LAE) as well as their mixture. In this research, spoilage bacteria were isolated from the rotten mustard tuber and used as the research object. In vitro antimicrobial experiments based on the checkerboard assay were performed to determine the minimum inhibitory concentration (MIC) of LAE and PS at different pHs, and the joint antimicrobial effect was examined and verified in the preservation of pickled mustard tuber. In addition, taking the most dominant isolated spoilage microorganisms as the research object, the peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) activities, the DPPH free radical scavenging rate, the protein content, and the malondialdehyde (MDA) content were determined under the action of LAE. The major spoilage microorganisms isolated were used as the test bacteria (inducing Virgibacillus halodenitrificans, Pseudomonas stutzeri and Penicillium janthinellum). The results showed that the MICs of LAE and PS were 16~32 mg/L and 256~1024 mg/L, respectively, with PS exhibiting shows a positive correlation between antimicrobial activities and acidity, and LAE acting oppositely. PS and LAE exhibited an additive or synergistic effect in the antimicrobial activities towards the test bacteria. The combined use of LAE and PS could inhibit (by 1 to 2 orders of magnitude) the proliferation of the microorganisms in packed pickled mustard tubers. Under the press of LAE, the POD, CAT and SOD activities, DPPH radical scavenge rate, protein content and MDA content decreased. LAE and PS can effectively inhibit the spoilage microorganisms in pickled mustard tuber, and their mix has a promising potential of enhancing preservation performance.Furthermore, the potential antimicrobial mechanisms of LAE might involve the decrease of membrane integrity and increase of oxidative stress of the microbial cells.

国家科技支撑计划项目（2015BAD16B03）；国家农业科技成果转化资金重点项目(2014GBC220152)；宁波市农科院院长基金项目（2020NKYP001）