In Vitro Characterization of Lactiplantibacillus Plantarum Strains: Probiotic Potential, Riboflavin Production, and Functional Properties.

Lactiplantibacillus plantarum is commonly present in the gut microbiota of healthy individuals, as well as in a wide range of fermented foods and dairy products. Its well-documented probiotic potential, ability to produce bioactive compounds, and contribution to food preservation make it a promising candidate for functional food development. In this study, twenty-four lactic acid bacteria (LAB) isolates were obtained from various samples. The isolates were identified using Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS), and all were showed a high similarity to the species L. plantarum. Their probiotic properties were evaluated through a series of in vitro assays. Among these, fourteen isolates exhibited tolerance to gastrointestinal tract conditions, cell surface properties, and significant antimicrobial activity. Only two strains showed substantial adhesion to mucins. In vitro screening showed a considerable antioxidant activity and efficient cholesterol assimilation, as well as β-galactosidase and proteolytic activities. All the strains exhibited remarkable levels of riboflavin (vitamin B2) secretion, reaching concentrations of 1,646 ± 377.92 ng/mL. Most of the selected strains displayed safe antibiotic resistance profile and no pathogenic potential, suggesting that they are promising candidates for further investigation in human applications. Based on these findings, three L. plantarum strains were selected as promising candidates for in vivo applications in both food and human health. These strains exhibit potential not only as probiotics agents, but also as natural bioactive additives for nutritional fortification and food biopreservation.