Rodney H. Perez1,2, Kohei Himeno2, Takeshi Zendo2 and Kenji Sonomoto2
Bacteriocins from lactic acid bacteria (LAB) are industrially important compounds that have been utilized as a safe food preservative replacing the potentially harmful synthetic chemical preservatives, Enterococcus faecium NKR- 5-3 is a novel LAB strain that produces five different bacteriocins‘ The critical fermentation factors, such as specific medium components and optimum incubation temperature that support the maximum production of multiple bacteriocins of strain NKR-5-3, were identified. Sucrose and yeast extract were found to be the preferred carbon and nitrogen sources for bacteriocin production of this strain, respectively. The highest bacteriocin production was observed when strain NKR-5-3 was incubated at 25°C. At incubation temperatures beyond 30°C, bacteriocin production was significantly reduced and completely ceased when further raised to 40°C, These findings possess remarkable practical implications as they can be vital in the future design of a cost-effective production system for these bacteriocins. Such a system would address the issue of the high production cost, which has remained the major barrier to the development of the large-scale industrial utilization of these important compounds.
Keywords: lactic acid bacteria, Enterococcus faecium, bacteriocin, multiple bacteriocin, bacteriocin production, fermentation factors