Characterization of Antibacterial Lactic Acid Bacteria Isolated from Moroccan fermented Olives

Abstract

The research for antibacterial activities of lactic acid bacteria isolated from Moroccan table olives, revealed 15 bacterial strains having an inhibitory activity against pathogenic germs: Listeria monocytogenes, Listeria innocua and Staphylococcus aureus; as well as Gram-negative germs, such as Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and others. From 127 samples of table olives, 143 bacterial strains with antibacterial effect were isolated by the double layer method, 15 strains were retained. All are Gram positive, catalase negative and non-sporulating. Cocci constitute 66.33% of the total effective. The remaining 33.33% are represented by bacilli/Ovoid. The lactic acid bacteria retained have a greater inhibitory effect against Gram positive and Gram negative bacteria. Listeria monocytogenes CECT 4032 and Staphylococcus aureus MBLA were inhibited by all the lactic strains studied. The smallest inhibition zones were recorded for the two isolates LB15 and LB96 against E. coli 87739, with diameter less than 10 mm.