GROWTH CURVE OF Lactobacillus plantarum STRAIN P158 AND ITS BACTERIOCIN CHARACTERIZATION

The characteristics of growth curve and sensitivity to antibiotics of L.plantarum strain P158 selected from fermented glutinous rice and its bacteriocin were studied.The results showed that the maximum biomass was up to 10~(11) cfu/ml at 36 h.The strongest inhibitation activity to Micrococcus luteus and Pseudomonas aeruginosa and the lowest pH(3.53)were observed after 40 h culture,and titer reached about 1145 IU/ml.It was suggested that the growth of bacteria was closely related to the producing of bacteriocin.The bacteriocin was sensitive to antibiotics,such as penicillins,tetracycline,macrolides and so on,but it was resistant to polymyxin B and most of aminoglycosides.The bacteriocin was stable in acid and high temperature conditions,but it was sensitive to trypsin,papain,pepsin and proteinase K.The bacteriocin had broad antimicrobial spectrum including most of gram-negative bacterium and gram-positive bacterium strains,and could inhibit some fungi,however,it almost had no active against LABs.These findings suggest that bacteriocin of strain P158 has the potential as a food bio-preservative.