Characterization of bacteriocins produced by lactic acid bacteria of industrial interest

PUJATO, S. A.; QUIBERONI, A. DEL L.; GUGLIELMOTTI, D. M.

BIOMOLECULES FROM NATURAL SOURCES: ADVANCES AND APPLICATIONS

John Wiley & Sons Ltd.

Lugar: Hoboken, New Jersey; Año: 2022; p. 458 - 469

Bacteriocins encompass a large family of ribosomally synthesised antimicrobial peptides antagonistic against microorganisms related (competing bacteria) or not (spoilage or pathogenic bacteria) to the producer bacterium. They have long been studied because of their huge potential as natural food preservatives that could be the perfect replacement of the extensively used but dangerous chemical preservatives. Different assays were carried out to assess optimal conditions (temperature and pH) for bacteriocin production, followed by the ability of Leuc. citreum MB1 to prevent the growth of List. monocytogenes by producing the antilisterial bacteriocin in a fermented-milk model. Our results showed that the highest production of bacteriocin was observed when Leuc. citreum MB1 was cultured at 25 °C and at pH values between 5 and 6, which are suboptimal growth conditions for this bacteriocinogenic strain. Leuc. citreum MB1 was able to delay List. monocytogenes growth at refrigerated temperature when they were co-inoculated in the fermented-milk model. Direct inoculation with the bacteriocin-producer strain presents the advantage of the in situ production of the antimicrobial compound and other metabolites than can contribute not only to safety but also to its organoleptic features of the fermented food. Besides, it is more cost-effective in comparison to the use of purified bacteriocin and subjected to less regulatory controls.