Molecular analysis of poultry meat spoiling microbiota and heterogeneity of their proteolytic and lipolytic enzyme activities

Abstract

Psychrotrophic Pseudomonas species P. fl uorescens, P. fragi and P. lundensis were found as predominant bacteria of chicken meat stored at chill temperature, which showed high level of molecular diversity, while isolates of the psychrotrophic yeasts Candida zeylanoides, Metschnikowia pulcherrima, Rhodotorula glutinis and Rhodotorula mucilaginosa formed clusters of high level similarity within the different species as revealed by RAPD-PCR analysis. Combination of multiplex PCR and sequencing of the rpoB gene resulted correct identifi cation of the Pseudomas isolates, while the routine diagnostic tests led to improper identifi cation in case of half of the isolates, which indicated the extended biochemical and physiological heterogeneity of the food-borne pseudomonads. Majority of P. fl uorescens and P. lundensis isolates were strong protease and lipase producers, while P. fragi strains were week or negative from this respect. Proteolytic and lipolytic activities of the isolated yeast strains were species specifi c and protease production was less frequent than lipolytic activities.