Influence of temperature and sakacin A concentration on survival of Listeria innocua cultures

The antimicrobial activity of sakacin A, a bacteriocin produced by L. sakei, was investigated at 30, 10 and 4 °C against L. innocua in stationary and lag phases of growth. When sakacin was added to L. innocua cells in stationary phase, two death kinetics were observed. Populations of L. innocua were reduced up to three log cycles when sakacin A was increased from 0 (control) to 1600 AU ml-1. When sakacin A was added to L. innocua cells in lag phase, lag time, inhibition time and rate were proportionally extended, and maximum population decreased when employing higher bacteriocin levels. Sakacin A was found to influence L. innocua growth, a microorganism able to grow at 4 °C. At refrigerated temperatures, the addition of sakacin A was found to inhibit L. innocua cell growth. Sakacin A may be considered a promising molecule to be used as antimicrobial agent to preserve the shelf life of refrigerated foods.