Novel method to extract large amounts of bacteriocins from lactic acid bacteria

TLDR

Bacteriocins produced by lactic acid bacteria bind to the cells of their producers and other gram‑positive bacteria. The study aimed to develop a novel isolation method for bacteriocins from lactic acid bacteria. The method exploits the near‑complete adsorption of bacteriocins at neutral pH to recover them from four lactic acid bacterial genera. By exploiting the near‑complete adsorption of bacteriocins at pH 6.0, the new method produced potent, concentrated preparations of pediocin AcH, nisin, sakacin A, and leuconocin Lcm1 with higher yields than precipitation, facilitating large‑scale production for food biopreservation.

Abstract

Antimicrobial peptides, bacteriocins, produced by lactic acid bacteria were adsorbed on the cells of producing strains and other gram-positive bacteria. pH was a crucial factor in determining the degree of adsorption of these peptides onto cell surfaces. In general, between 93 and 100% of the bacteriocin molecules were adsorbed at pHs near 6.0, and the lowest (< or = 5%) adsorption took place at pH 1.5 to 2.0. On the basis of this property, a novel isolation method was developed for bacteriocins from four genera of lactic acid bacteria. By using this method we made preparations of pediocin AcH, nisin, sakacin A, and leuconocin Lcm1 that were potent and concentrated. This method produced a higher yield than isolation procedures, which rely on precipitation of the bacteriocins from the cell-free culture liquor. It is simple and can be used to produce large quantities of bacteriocins from lactic acid bacteria to be used as food biopreservatives.