UTILIZATION OF BIO AND RADIO TECHNOLOGY PROCESSES IN BACTERIOCIN PRODUCTION BY LACTIC ACID BACTERIA

Abstract

This study was planned to isolate Lactic Acid Bacteria (LAB) with potential Bacteriocins production as inhibitory bioactive peptides from different products from locally Egyptian market. The inhibitory activities were selected against several gram-positive and gram-negative indicator bacterial pathogens through disc diffusion methodology which was carried out via antagonistic between partially purified bacteriocin of LAB strains and isolates against target pathogens. After chosen the best LAB efficiency the optimal physical and chemical factors were determined to improve the production of bacteriocin from two isolates and one strain of LAB. Finally, the influence exposure of gamma rays was studied on bacteriocin production of chosen LAB at different doses.

The obtained results could be summarized as follows: 1. Lactic Acid Bacteria (LAB) are largely spread in numerous of food products, have generally characterizes as gram-positive, catalase-negative, have various morphology shape (rod, cocci or poly-form), and obligatory sugar fermentation producing acid. 2. LAB requirement microaerophilic condition to growth, thus double layer method was the most efficient technique used to isolate, Mostly isolates were bacilli shape. 3. The partially purified Bacteriocin was achieved through two-step sequentially. Firstly, at low centrifugation of LAB culture was obtained supernatant namely the crude bacteriocin, which has other