In Vitro Assessment of Biological and Functional Properties of Potential Probiotic Strains Isolated from Commercial and Dairy Sources

Abstract

Probiotic species have garnered significant attention for their health benefits extending beyond gastrointestinal health. This study investigated the biological and enzymatic functions of selected probiotic species, specifically Lacticaseibacillus rhamnosus (formerly Lactobacillus rhamnosus), Lactiplantibacillus plantarum (formerly Lactobacillus plantarum), Lactobacillus acidophilus, and Lactobacillus delbrueckii, among others, through in vitro experiments. Enzymatic activities, including hemolytic, lipase, esterase, and protease functions, were evaluated. Antioxidant capacity was assessed using DPPH radical scavenging assays, while antimicrobial efficacy was tested against common pathogenic bacteria. Antibiotic-resistance patterns were analyzed to ascertain their safety for human consumption. Furthermore, simulated digestive fluid tolerance experiments were conducted to evaluate survival in the gastrointestinal tract. The findings indicate that these probiotic strains exhibit diverse functionalities beyond intestinal health, with potential roles in digestion, oxidative stress reduction, and immune support. This study provides valuable insights into the functional diversity of probiotics, suggesting their broader applications in health and nutrition. Future research should focus on in vivo validation, mechanism elucidation, and clinical studies to determine optimal dosages and strain-specific benefits.

Keywords: DPPH scavenging; antibiotic resistance; antimicrobial effects; antioxidant activity; enzymatic activity; gastrointestinal tolerance; probiotics.

Figure 1

Antimicrobial activity test results.

Figure 2

Antioxidant activity of bacterial strains.