Studying on the optimal bacteriocin production condition of Lactococcus lactis KLDS4.0325

The fermentation conditions of L. lactis KLDS4.0325 isolated from self- made koumiss Xinjiang were optimized for bacteriocin production by double- plate method.The inhibitory zone diameter( mm) was used as evaluation index and quantified against Escherichia coli ATCC 25922. The result showed that the bacteriocin production reached the maximal value under the condition of 33 ℃,original p H7.0 and 120 r / min for 20 h.Further,under the optimal culture condition,the inhibitory zone diameter was 25.26 mm and the titer of bacteriocin was reached up to 5383.07 IU / mL.