Partial characterization of heat-stable, antilisterial and cell lytic bacteriocin of Pediococcus pentosaceus CFR SIII isolated from a vegetable source

Abstract

Heat-stable, antilisterial and cell lytic bacteriocin-producing Pediococcus pentosaceus CFR SIII isolated from a vegetable source (cucumber) was partially characterized. The isolate was identified by microbiological methods and 16S rRNA gene sequences. The bacteriocin produced by this isolate, designated as PP SIII, was active against several Gram-positive and Gram-negative food-borne pathogens and food spoilage lactic acid bacteria. The apparent molecular mass of the partially purified bacteriocin was found to be ∼5 kDa by Tricine SDS-PAGE. It was stable at pH 3–5 and at 121°C for 15 min and inactivated by various proteases. The mode of action of the bacteriocin through FTIR analysis and glycolytic activity assay revealed cell lytic activity against the indicator Pediococcus acidilactici B1153 by complete cell lysis, depletion of intracellular solute and disruption of pH gradient. The study envisages the potentiality of the isolate in vegetable preservation or as an adjunct culture in various cheese varieties to avoid chemical preservatives.