Characterization of lactocin lc-09 produced by lactobacillus acidophilus

The kinetics of lactocin LC-09 synthesis and the effect on the growth of LC -09 was determined at different temperatures i.e. 37 ˚C, 40 ˚C, 45 ˚C and 50 ˚C. Of all the temperatures tested, 37 ˚C, 40 ˚C and 45 ˚C displayed bacteriocin production in the early exponential phase. However, no lactocin production was observed at 50 ˚C. Cell dry mass and µ max was also determined at such temperatures. Maximum cell dry mass obtained at 37˚C and 45 ˚C and µ max increased as the dry cell mass increased. Heat stability of lactocin LC-09 indicates that lactocin LC- 09 is heat stable up to 100 ˚C even heating for 50 minutes but high temperature has marked effect on lactocin production during growth. Effect of pH on lactocin LC-09 indicates that the lactocin is active at acidic pH.