EFFECT OF pH AND HEAT TREATMENT ON BACTERIOCIN ACTIVITY OF Pediococcus pentosaceus IO1, Tetragenococcus halophilus PO9 AND Lactobacillus cellobiosus BE1

Three lactic acid bacterial (LAB) strains; Pediococcus pentosaceus IO1, Tetragenococcushalophilus PO9, and Lactobacillus cellobiosus BE1 isolated from different traditionallyfermented products were evaluated for their bacteriocin activity against Staphylococcus aureusand the influence of pH and heat treatment on their bacteriocin activity was assessed. The crudebacteriocins produced by the LAB strains were highly thermostable, retaining their activity evenafter heat treatment at 115 oC for 15 min, and stable at pH range of 2 – 9 with higher activity atacidic pH (pH 2 and 5). These results indicate that the bacteriocins produced bybacteriocinogenic LAB isolates could be used as biopreservatives in acidic and heat-processedfoods.Keywords: Bacteriocin, Lactobacillus cellobiosus, Pediococcus pentosaceus, Tetragenococcushalophilus.