抑制芽孢杆菌乳酸菌的筛选鉴定及其抗菌物质的分离纯化

赵圣明; 曹雪珂; 赵岩岩; 马汉军; 何鸿举

doi:10.13386/j.issn1002-0306.2018.11.025

抑制芽孢杆菌乳酸菌的筛选鉴定及其抗菌物质的分离纯化

Screening and identification of lactic acid bacteria with anti-Bacillus spp. activities and isolation and purification of antimicrobial substance

摘要

摘要: 从朝鲜族辣白菜中分离筛选得到1株对芽孢杆菌具有广谱抑菌活性的菌株JLY-7,该菌株发酵液对蜡样芽孢杆菌、枯草芽孢杆菌、凝结芽孢杆菌、巨大芽孢杆菌、短小芽孢杆菌、嗜热脂肪地芽孢杆菌、多粘类芽孢杆菌等食品中常见的腐败性和致病性芽孢杆菌具有较强的抑制作用。对菌株JLY-7进行形态学特征、生理生化特征及16S rRNA序列分析,鉴定其为植物乳杆菌。利用正丁醇萃取、凝胶过滤层析(Sephadex LH-20)和半制备液相色谱纯化等手段对该菌株所产抗菌物质进行分离纯化,得到单一活性抑菌组分,经高分辨电喷雾电离质谱确定该抗菌物质的分子量为694.129 Da。通过蛋白酶处理结果表明,该抗菌物质对常见的蛋白酶均非常敏感。本研究可为乳酸菌抗菌物质控制食品中芽孢杆菌奠定理论基础。

Abstract: A new strain with broad-spectrum anti-Bacillus spp. activity, JLY-7, was isolated from Korean traditional fermented kimchi samples. The cell-free supernatant produced by the strain JLY-7 showed a high inhibitory activity towards common pathogenic and food-spoiling Bacillus spp. such as Bacillus cereus, Bacillus subtilis, Bacillus coagulans, Bacillus megaterium, Bacillus pumilus, Geobacillus stearothermophilus and Paenibacillus polymyxa. The strain JLY-7 was identified as Lactobacillus plantarum by morphological, physiological and biochemical characteristics and 16S rDNA sequence analysis. Then, the antimicrobial substance was isolated and purified using butanol extraction, gel filtration chromatography (Sephadex LH-20) and semi preparative HPLC and a single antimicrobial component was obtained. The molecular mass of the purified antimicrobial substance was estimated to be 694.129 Da by HR-ESI-MS. Protease treatment results showed that the antimicrobial substance was sensitive to all proteases. The research was conducted to lay a theoretical foundation for controlling Bacillus spp. in food by antimicrobial substance produced from lactic acid bacteria.