Detection of bacteriocins produced by Lactobacillus plantarum strains isolated from different foods.

Bacterial strains (106 in toto) isolated from different foods and identified as Lactobacillus plantarum were screened for antagonistic activities against other bacteria under conditions which eliminated the effects of organic acids and hydrogen peroxide. Five isolates were shown to be bacteriocin producers, and the bacteriocins, on the basis of their host range inhibition and cross inhibition were all different. The bacteriocins were preliminarily characterized by temperature stability, sensitivity to proteolytic, lipolytic and glycolytic enzymes and precipitation with ammonium sulphate.