Caseinolytic proteases of Lactobacillus and Lactococcus strains isolated from fermented dairy products

Proteases of Lactobacillus and Lactococcus strains catalyze casein degradation in fermented dairy products, which can result the production bioactive peptides. Proteolytic properties a selection lactic acid bacteria (LAB) previously isolated Croatia, including lactis strains, are described. All showed an Fmc+ phenotype that be associated with efficient growth milk. The significant caseinolytic effect, after incubation culture supernatant or concentrated cell biomass, was observed for Levilactobacillus brevis D6 Lactiplantilactobacillus plantarum D13 optimal medium, while Lc. ZGBP5-32 SF9B skimmed To assess LAB milk, acidification rate monitored. Statistically, capacity determined L. medium by proteolytic strain helveticus M92 After extraction proteinases from activity, protein samples were analysed SDS-PAGE method. extract ZGZA7-10, retained activity even at very low concentrations. ultrafiltration improved possibly contained putative protease, as decrease contaminating proteins confirmed SF9B, fermentum D12 D13.