Antimicrobial and technological properties of lactic acid bacteria isolated from traditional Colonial-type cheese from the south of Brazil

Abstract

The present study aimed to evaluate the safety, antimicrobial and technological properties of lactic acid bacteria from artisanal Colonial-type cheese marketed at streets fair in Pelotas, RS. A total of 73 isolates were characterized as BAL after Gram’s method and catalase test. All strains were gelatinase and DNase negative, regarding hemolytic activity, seven were detected as α and two as β-hemolytic, exerting 63 BAL that demonstrated sensitivity to the chloramphenicol and tetracycline antibiotics. The antagonistic activity was verified by the spot-on-the-lawn method and the evaluation of the production of bacteriocins by the diffusion technique in wells. Four BAL (C1BAL10, C2BAL2, C4BAL1, and C4BAL5) were able to produce BLIS anti-Listeria, extracellular proteinases, and of these C2BAL2 and C4BAL1 were characterized as rapid acidifying cultures. After molecular testes were identified as Lactobacillus acidophilus and Lactococcus lactis. The results suggest two strains as potential candidates in the biopreservation of dairy products.