对乳酸乳球菌素Lacticin LLC518在不同pH条件下产生菌的吸附作用进行研究,结果表明,pH 6.0时吸附率达100%,pH 2.0时吸附率为0。利用该特性,可将产生菌细胞从发酵液中分离,制备Lacticin LLC518粗制品。通过与硫酸铵沉淀样品进行对照,表明pH吸附法具有良好的分离效果,Lacticin LLC518的回收率为20%,纯化倍数高达83.02。

The adsorption rates of Lacticin LLC518 on Lactococcus lactis subsp.lactis 518 at different pH conditions were studied.The results showed that the adsorption rate was 100% at pH 6.0 while no Lacticin LLC518 was adsorbed at pH 2.0.Therefore,the crude Lacticin LLC518 was prepared from the cell-free supernatant of the L.lactis subsp.lactis 518 culture when the exterior environment had a pH of 6.0 and 2.0 by absorbing and desorbing Lacticin LLC518,respectively.The pH absorption method has an obvious advantage superior to the ammonium sulphate precipitation method for its better absorption effect when the crude Lacticin LLC518 from precipitation with ammonium sulfate as a control.The specific activity of Lacticin LLC518 was increased 83.02 fold with a yield of 20%.