A NOVEL ANTIMICROBIAL ACTIVITY OF A PAENIBACILLUS-POLYMYXA STRAIN ISOLATED FROM REGIONAL FERMENTED SAUSAGES

A Strain isolated from Argentinean regional fermented sausages was fou nd to produce and secrete a compound that inhibited growth of Lactobac illus strains used as indicators. It was characterized as Paenibacillu s polymyxa (P13). The antimicrobial activity, named polyxin, was obtai ned from culture supernatant fluid of late stationary phase and was in hibitory to actively growing cells. It was effective against a wide ra nge of Gram-positive and Gram-negative bacterial species tested includ ing foodborne pathogens. Bacteriocin-like properties such as proteinac eous nature (sensitive to proteases), insensitivity to organic solvent s and chelators, stability to heat (up to 10 min at 90 degrees C), and acidic pH but instability in alkaline conditions, were determined. A molecular mass of 10 kDa was estimated by molecular gel filtration.