Identification and characterisation of lactobacilli isolated from an artisanal cheese with antifungal and antibacterial activity against cheese spoilage and mycotoxigenic Penicillium spp.

Given the importance of lactic acid bacteria (LAB) in dairy products, this study assessed the antimicrobial properties of lactobacilli against some toxigenic Penicillium spp and pathogenic bacteria commonly found in cheese. Lactobacilli previously isolated from an artisanal Brazilian cheese (n =& nbsp;32) were identified to species level by amplification and sequencing of the 16S rRNA gene and tested against Penicillium commune, Penicillium expansum, Penicillium nordicum and Penicillium roqueforti through an overlay method. The most resistant mould was P. commune-M35 and the major species that exhibited inhibition against all Penicillium spp. tested was Lactiplantibacillus plantarum. Cell free supernatants of two selected L. plantarum isolates (L119 and L49) were used to determine the antifungal and antibacterial activity using impedance and turbidimetric techniques, respectively. The antimicrobial activity showed inhibition beyond acid. Since L. plantarum-L49 and L119 have the ability to inhibit undesirable microorganisms, they could be candidates as novel protective cheese cultures. (C)& nbsp;2022 Elsevier Ltd. All rights reserved.