Probiotic Properties of Lactobacillus Species Isolated from Local Traditional Fermented Products

The present study aims to isolate Lactobacillus species from locally fermented vegetables and to characterize selected isolates for their probiotic potential. Seventeen Lactobacillus strains (9 Lactobacillus plantarum 1, 3 Lactobacillus pentosus, 2 Lactobacillus brevis 1, 2 Lactobacillus brevis 3 and 1 Lactobacillus salivarius) were isolated and tested for their probiotic potential. This included survival in gastrointestinal simulated juice, antagonistic activity against Salmonella typhimurium, Escherichia coli, Bacillus cereus and a methicillin-resistant Staphylococcus aureus (MRSA) isolate, bile tolerance and antibiotic resistance to 8 antibiotics. Most isolates, especially Lactobacillus plantarum 1, were tolerant to the acidity and intestinal conditions after exposure for three and four hours, respectively, with reduction less than one log cycle of the starting CFU/ml. The same trend was observed in respect to bile tolerance with slight variations. All isolates inhibited the growth of the tested pathogens and were the most effective against MRSA isolate. As for antibiotic resistance, it was pronounced against kanamycin, ampicillin, erythromycin and tetracycline. Some isolates (M3, M5, M6, M12, B14) showed a resistance to 6 or more antibiotics of those tested. These results prove that the traditionally fermented vegetables are a good source for probiotic Lactobacillus. However, further in vivo studies are needed to substantiate the potential of these isolates.