Purification and characteristics of Bacteriocin produced by Lactobacillus Salivarius LH1F

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.