College of Food Science and Engineering, Jilin Agricultural University, Changchun 130118, China.
College of Chinese Herbal Medicine, Jilin Agricultural University, Changchun 130118, China.
Biomed Res Int. 2018 Dec 30;2018:5416725. doi: 10.1155/2018/5416725. eCollection 2018.
. Lactic acid bacteria (LAB) were isolated from fermented foods, such as glutinous rice dough, corn noodle, chili sauce, potherb mustard pickles, and stinky tofu, in northeast China. LAB strains with antimicrobial activities were screened, and seven of these strains were identified as , , and through 16S rRNA gene analysis. After the supernatant of LAB was treated with proteinase K, pepsin, and papain, their antibacterial effect almost disappeared. Most strains with antibacterial activities were highly resistant to heat (65°C-121°C), acidity (pH 2-6), and alcohol. The antimicrobial effect of most strains treated with the Tween-80 surfactant was significantly reduced, and the antibacterial property of T4 was even lost. Ammonium sulfate precipitation, PCR, and nanoLC-ESI-MS/MS results confirmed that T8 produced antibacterial substances belonging to a protein family, and its zone of inhibition against pathogens significantly increased (>13 mm). In bacterial growth inhibition experiments, the colony count of was up to 10 CFU/mL in the 3⁎de Man, Rogosa, and Sharpe (MRS) group, and this value was more than that in the 3⁎S6 supernatant group (10 CFU/mL) and the control group (10 CFU/mL) at 12 h. This study provided a basis for the selection of antimicrobial peptides and the development and utilization of LAB.
从中国东北地区的发酵食品（如糯米面团、玉米面条、辣椒酱、芥菜泡菜和臭豆腐）中分离出了乳酸菌（LAB）。筛选出具有抗菌活性的 LAB 菌株，并通过 16S rRNA 基因分析鉴定出其中 7 株为 、 、 。用蛋白酶 K、胃蛋白酶和木瓜蛋白酶处理 LAB 上清液后，其抑菌作用几乎消失。大多数具有抗菌活性的菌株对热（65°C-121°C）、酸度（pH 2-6）和酒精具有高度抗性。大多数具有抗菌活性的菌株经吐温-80 表面活性剂处理后，抑菌效果明显降低，T4 的抑菌活性甚至丧失。硫酸铵沉淀、PCR 和 nanoLC-ESI-MS/MS 结果证实 T8 产生的抗菌物质属于一种蛋白质家族，其对病原体的抑菌圈显著增大（>13mm）。在细菌生长抑制实验中，在 3⁎de Man、Rogosa 和 Sharpe（MRS）组中 的菌落数高达 10 CFU/mL，而在 3⁎S6 上清液组（10 CFU/mL）和对照组（10 CFU/mL）中，该值在 12 小时时达到 10 CFU/mL。本研究为抗菌肽的选择和 LAB 的开发利用提供了依据。
