Lactic Acid Bacteria Isolated from Dairy Products Exhibit Probiotic Potential and Anticancer Activity

Background: In this study, we aimed to isolate bacterial strains from curd and buttermilk samples to explore their probiotic and anticancer potential. Methods: We isolated five bacterial strains from curd and buttermilk samples sourced from various origins. Identification was performed using 16S rRNA gene sequencing. Probiotic potential was assessed through tolerance tests to low pH and bile salt concentration. Antimicrobial and co-aggregation activities were evaluated for selected strains. Cell-free supernatants (CFS) were tested for anticancer activity against cervical and breast cancer cell lines. Result: Among the isolated strains, Limosi lactobacillus fermentum K-2, L. fermentum D-1, Weissella confusa U-2, Lactobacillus delbrueckii Br and L. delbrueckii M-2 were identified by 16S rRNA gene sequencing. Strains K-2, D-1 and U-2 exhibited probiotic potential with high tolerance ( greater than 90%) to low pH (3.0) and bile salt (0.3%) concentration. Strain K-2 showed efficient antimicrobial and co-aggregation activity against clinical pathogens. Additionally, CFS of the selected LAB strains displayed anticancer activity against cervical and breast cancer cell lines. The findings suggest that the isolated dairy probiotic has potential utility in functional food and therapeutic applications.