Probiotic potential and bioactive properties of Lactococcus lactis MSH-08 isolates from fermented dairy products: Antimicrobial, antioxidant, and anticancer activities

Lactococcus lactis has a major commercial role as starter cultures in fermented dairy products (FDP), food/feed fortification, and vaccine production. This study was designed to assess the probiotic characteristics, antioxidant, anticancer and antimicrobial activities of L. lactis from FDP. Thirty-five FDP samples were tested for potential probiotic Lactococcus spp. with anticancer and antibacterial activities. Biochemical profiling and 16S rDNA sequencing confirmed that the isolates were L. lactis MSH-08 strains. Antioxidant and Antibacterial activity of the Lactococcus isolates (n = 8) was found to be anti-Gram-positive bacteria (G & thorn;) i.e., Staphylococcus aureus DSM 1104 and Listeria monocytogenes LMG 10,470) and Gram-negative bacteria (G) i.e., S. typhimurium LMG 10,395, and Escherichia coli LMG 8223). The eight isolates of L. lactis showed an antimicrobial spectrum against both pathogenic G+ and G-. The potential probiotic strain and the other isolates showed the feasibility of these isolates at a small range of pH (3) and bile salts (0.3 %). The microfiltration of these strains has many bioactive molecules (phenolic and flavonoid compounds and organic acids). The partially purified filtration exhibited antimicrobial, antioxidant and anticancer activity. The antimicrobial of L. lactis MSH-08 strain showed activity against S. typhimurium LMG 10,395 (16.67 mm), L. monocytogenes LMG 10,470 (17.33 mm) and E. coli LMG 8223 (17.67 mm). The cell-free supernatant of L. lactis MSH-08 strain exhibited the lowest IC50 (half maximal inhibitory concentration) value at 112.93 +/- 1.87 mu g/mL and demonstrated a toxicity rate of 97.41 % for cancerous cells at a level of 1000 mu g/mL.