Biodiversidad bacteriana del queso Paipa:selección de bacterias ácido lácticas y caracterización de sus compuestos antibacterianos

Abstract

The objective of this work was to obtain information on the microbiota of Paipa cheese, determine the quality of Paipa cheese produced by formal and informal companies, characterize potentially pathogenic bacteria, determine its susceptibility to antimicrobials and its tolerance to biocides. It also aimed to characterize and purify the antimicrobial compounds produced by selected lactic acid bacteria from Paipa cheese. The results indicated that Firmicutes and Lactococcus were the main phylum and genus found in the cheeses. 100% of the samples from formal and informal producers present a regulation on coliform and staphylococcal populations above the limits established by the Colombian. L. monocytogenes was positive in 38% of the samples. The coliforms that prevailed were Escherichia coli (22%) and Citrobacter freundii (22%). The coliforms (30%) were multi-resistant to antibiotics, but susceptible to biocides. Two lactic acid bacteria with bacteriocinogenic activity (Leuconostoc mesenteroides and Lactococcus lactis) were identified. The antimicrobial substances produced by these bacteria match the characteristics of leukocin and lacticin respectively.