Assessing Lactobacilli strains from Algerian traditional dairy products for probiotic potential benefits

This study explores the probiotic potential of five lactic acid bacteria species (LAB) isolated from traditional Algerian dairy products, with the goal of advancing the development of customized probiotics for innovative applications within the food industry. Tailoring probiotics for specific uses represents a significant advancement in this field. The focus is on five species: Limosilactobacillus fermentum, Lactiplantibacillus pentosus, Lactiplantibacillus plantarum, Lacticaseibacillus paracasei ssp paracasei, and Lactiplantibacillus paraplantarum, all identified through MALDI-TOF mass spectrometry, with confirmation via PCR and 16S rRNA sequencing. The probiotic potential of these strains was evaluated through in vitro experiments assessing tolerance to bile salts and acidity, hydrophobicity, hemolytic activity, sugar fermentation profiles, and resistance to antibiotics and phenols. Results indicated that all the strains displayed significant survival rates at pH 3, ranging from 77.18% f 1.74-93% f 1.95. Bile salt tolerance varied among strains, with survival rates between 60.77% f 2.10 and 91.46% f 1.68 at a 0.3% concentration, and between 53.91% f 2.39 and 87.02% f 2.57 at a 0.5% concentration. Hydrophobicity tests demonstrated moderate adhesion capabilities. Notably, only three strains exhibited resistance to 0.4% phenols, with growth percentages between 29.60% f 2.03 and 45.97% f 5.49. Antibiotic susceptibility tests revealed a high sensitivity to various antibiotics, while resistance was noted for cefoxidim, tetracycline, and vancomycin, with the exception of L. fermentum, which remained sensitive to vancomycin. All tested strains were non-hemolytic and capable of fermenting a majority of sugars. Overall, the isolated strains showcase promising probiotic characteristics, providing opportunities for innovation in the food sector by developing new fermented dairy products that meet consumer demands for health and naturalness.