唾液乳杆菌LH1F所产细菌素的纯化及其生物学特性研究
Purification and characteristics of Bacteriocin produced by Lactobacillus Salivarius LH1F
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摘要: 本文对唾液乳杆菌(Lactobacillus Salivarius)LH1F发酵液中的抑菌物质的特性进行了研究,在排除菌体细胞、有机酸、过氧化氢干扰及经胰蛋白酶、胃蛋白酶处理后,确定抑菌成分为肽类细菌素,然后经过60%硫酸按盐析及超滤初步纯化后,对其生物学特性进行了研究。结果表明,唾液乳杆菌LH1F所产的细菌素具有良好的热稳定性,121℃处理30 min仍保留75.5%的抑菌活性;在p H2.0p H5.0条件下稳定;对胃蛋白酶、胰蛋白酶和蛋白酶K敏感;该细菌素具有较广的抑菌谱,对供试的多种革兰氏阳性菌(G+)及革兰氏阴性菌(G-)具有明显的抑制作用,为作为天然食品防腐剂的进一步研究奠定基础。Abstract: The antibacterial characteristics of bacteriocin produced by Lactobacillus Salivarius LH1 F were carried out.After eliminating the interferences of bacterial cells,organic acids and hydrogen peroxides,the antimicrobial activity of the fermentation supernatant was little difference. After treatment with trypsin or pepsin,its inhibitory activity was decreased,indicating that the antibacterial component was bacteriocin- like substance. The cell- free supernatant of Lactobacillus Salivarius LH1 F was precipitated by 60% ammonium sulphate. After ultrafiltration,the biological characteristics of bacteriocin were as follows.This bacteriocin exhibited good heat stability( 75.5%) after treating at 121 ℃ for 30 min,also it showed good stability when the p H was between 2.0 and 5.0. Its inhibitory activity revealed an obvious decrease when treated with pepsin,trypsin and protease K.In addition,it had a wide antibacterial spectrums,it could inhibit the growth of Gram- positive bacteria and Gram- negative bacteria. The properties of Lactobacillus Salivarius LH1 F indicated that it had a potential application as a natural bio-preservative to improve the safety of food products.