ABSTRACT

 The aim of this work was to investigate the antimicrobial activities of crude bacterocin extract of LAB against Staphylococcus aureus and Escherichia coil. A total of fifty, ten each of different fermented food which include ogiri, Honey, Palm wine, yogurt and ogi. Were purchased from the local market named Ndoro in Ikwuano L.G.A Abia State. The samples were collected using sterile bottle to the laboratory. One gram of the sample was mixed with 9m1 of distilled water, O.lml was cultured on Mann Rogosa Sharpe (MRS) agar plates and incubated 37°C for 24hours. After incubation five lactic acid bacteria were identified as Leuconostoc spp., Lactobacillus bulgaricus, Lactobacillus plantarum, Lactobacilius brevis and Lactococcus lactis. The percentage occurrence of the isolates showed that Lactobacilius piantarum had the highest percentage occurrence of 14(34.1%) followed by Lactobacillus bulgaricus 6 (14.6%), Lactobacillus brevis and Lactococcus lactis showed same occurrence of 4(9.8%) respectively while Leuconostoc specie 3(7.3%) showed the least percentage occurrence. The five isolates were cultured in Mann Rogosa Sharpe (MRS) broth and incubated at 3 7°c, after incubation the cell free supernatant was obtained by centrifugation at 10,000 rpm for 1 5mins .The species of bacteriocin producing Lactic acid bacteria exhibited the highest inhibitiory activity against Staphylococcus aureus whereas Escherichia coil was found resistant to the different concentrations of crude bacteriocin. This study revealed the possibility of using bacteriocin as food biopreservative to control food spoilage and pathogenic bacteria.