Phylogenetic Analysis and In Vitro Evaluation of Probiotic Attributes of Lactobacillus acidophilus and Lactiplantibacillus plantarum Subsp. plantarum Strains Isolated From Fragaria ananassa.

Lactic acid bacteria (LAB) strains are a group of probiotics that have gained significant attention due to their potential to modulate the gut microbiota and promote human health. This study aims to characterize the commendable probiotic properties of LAB isolated from Fragaria ananassa (strawberry) samples collected in Navsari, South Gujarat, India. LAB strains are essential for gastrointestinal health and were meticulously assessed for critical probiotic traits, including bile and acid resistance, bile salt hydrolysis activity (BSH), resistance to antibiotics and lysozyme, exopolysaccharide (EPS) production, α-glucosidase activity, antibacterial activity, and diverse cell surface properties. The LAB strains exhibited varying survival rates in simulated gastric (3.55-7.05 log CFU/mL) and intestinal environments (1.86-6.40 log CFU/mL). Moreover, the ability of the bacteria to survive in bile salts varied from 26.10% to 96.55% for 0.3% oxgall and from 15.69% to 79.69% for 1.0% oxgall. Auto-aggregation rates significantly increased after 24 h for all isolates. ST3 displayed the highest hydrophobicity values (75.28% with xylene and 92.12% with chloroform). All isolates demonstrated resistance to lysozyme, vancomycin, and kanamycin. ST3 exhibited notable exopolysaccharide production (0.61 mg/mL) and displayed 46.55% α-glucosidase activity. Molecular characterization confirmed the identities of potent LAB isolates ST2 as Lactobacillus acidophilus and ST3 as Lactiplantibacillus plantarum subsp. plantarum. These findings illuminate the significant probiotic potential of these specific LAB isolates, providing valuable insights for further research and the development of probiotic-based interventions targeting gastrointestinal disorders.