In vitro Assessment of Some Probiotic Properties of Lactobacillus fermentum Isolated from Pickled Garlic

Background: Dominant Lactic Acid Bacteria (LAB) originally isolated from traditional non-dairy fermented foods, may harbor unique characteristics such as probiotic properties. In this research, probiotic potential of dominant LAB isolated from pickled garlic was studied. Methods: After isolation of dominant LAB from pickled garlic produced with apple cider vinegar, the isolate was identified by Polymerase Chain Reaction (PCR). Probiotic properties of mentioned isolate including survival in simulated conditions of gastrointestinal tract; antibacterial effects against Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and Salmonella enterica; ability of aggregation with these food-borne indicators; and finally antibiotic susceptibility of the isolate were investigated. Results were also analyzed statistically by SPSS software. Results: Sequencing results of PCR products identified Lactobacillus fermentum as dominant LAB in pickled garlic. L. fermentum had 36.30% and 66.08% survival in pH 2 and 0.3% bile salt after 3 and 4 h incubation, respectively. Inhibition zone diameter of L. monocytogenes and aggregation ability of the LAB isolate with L. monocytogenes was significantly (p<0.05) higher than the other indicators. Furthermore, L. fermentum was resistant to norfloxacin, streptomycin, kanamycin, nalidixic acid, and vancomycin. Conclusion: L. fermentum isolated from pickled garlic had high potential for using as probiotic bacteria in food and medicinal applications.