抑霉乳酸菌的筛分及其抑菌特性研究

Study on the screening and bacteriostatic characteristics of mildew-inhibiting Lactobacillus

试验旨在获取生物抑霉的优良菌株以及为质量安全青贮饲料生产提供高效菌剂。从青贮饲料、酸奶以及奶豆腐中分离纯化出乳酸菌和霉菌,并且通过双层平板法对具有抑制霉菌活性的乳酸菌菌株进行筛选,测定其上清液抑霉效果;采用蛋白酶处理和高温处理法分析乳酸菌抑霉的有效成分。结果表明:分离筛选的乳酸菌和霉菌经鉴定为植物乳杆菌和黄曲霉菌,且植物乳杆菌对黄曲霉菌的生长有明显抑制作用。蛋白酶处理对乳酸菌无细胞上清液的抑菌活性有不同影响,而加热处理并不改变其抑菌效果。研究表明,植物乳杆菌对黄曲霉菌生长有明显的抑制作用,推测其抑菌活性物质为蛋白质、肽类等,并且这些抑菌活性物质的热稳定性较高。

The study aimed to obtain excellent strains of biological mold inhibition and provide high-efficiency fungi for the production of quality and safe silage. The lactic acid bacteria and molds were isolated and purified from silage, yogurt and milk curd. The lactic acid bacteria strains with mildew inhibition activity were screened by double plate method, and the mildew inhibition effect of their superliquid was measured. The effective components of lactic acid bacteria were analyzed by protease treatment and high temperature treatment. The separated and screened lactic acid bacteria and molds were identified as Lactobacillus plantarum and Aspergillus flavus, and Lactobacillus plantarum had obvious inhibitory effect on Aspergillus flavus. Protease treatment have different effects on the antibacterial activity of the cell-free supernatant of lactic acid bacteria, but heat treatment does not change its antibacterial effect. Lactobacillus plantarum has an obvious inhibitory effect on Aspergillus flavus. It was speculated that its antibacterial active substances are proteins,peptides, and the thermal stability of these antibacterial active substances is high.