Lactic acid bacteria (LAB) are Gram-positive, catalase-negative, oxidase negative, non-sporulating, microaerophilic bacteria, referred as probiotics as there are many species from this bacterial group produce several antibacterial compounds including bacteriocins. Various bacteriocins differ in their activity range where they are either effect only on related species and genera (narrow activity range) or effect on other unrelated genera (wide activity rang). Bacteriocin production was found to be dependent on different factors environmental and cultural conditions as well as the producer strain itself. This study determined the activity range of Lactobacillus acidophilus ATCC 4356 and Lactobacillus plantarum atcc 8014, optimized the different conditions for the maximum bacteriocin production and finally, characterized the produced bacteriocins partially.
Key words: Bacteriocin, probiotic, Lactobacillus, environmental conditions and Activity range