肠球菌素的分离提取及其在牛乳杀菌中的应用

Purification of the Bacteriocin Produced by Enterococcus durans and Its Application in Milk Sterilization

从发酵奶酪制品中分离出1株耐久肠球菌(Enterococcus durans)41D,其培养过程中产生能抑制李斯特菌生长的肠球菌素。本实验通过pH值吸附法将该肠球菌素分离提纯,产率约为45.7%。并进一步研究发现,当在牛乳中添加终浓度为256 AU/mL的肠球菌素时,不同的处理方式(高温杀菌,巴氏杀菌)不影响实验期间(15 d)肠球菌素抑菌活性的发挥。该肠球菌素在牛乳中应用时能够有效抑制单增李斯特菌的生长并对牛乳有较好的保存效果。

One Enterococcus durans strain designated 41 D was isolated from fermented cheese products. The strain produced bacteriocin that can inhibit the growth of Listeria monocytogenes. In this study, a pH absorption method was used to separate and purify the bacteriocin with a yield of about 45.7%. Further investigation suggested that when the bacteriocin was added into milk samples at a final concentration of 256 AU/mL, its antibacterial activity was not affected by different treatments including high-temperature sterilization and pasteurization during the experiment period. When applied in milk, the bacteriocin could effectively inhibit the growth of Listeria monocytogenes. These results have provided the basis for the development of new natural food preservatives using this bacteriocin.