Isolation, Characterization and Identification of Lactic Acid Bacteria as Probiotic

Abstract

Lactic acid bacteria that grow as the adventitious microflora of foods or that are added to foods as cultures are generally considered to be harmless or even an advantage for human health. The objective of this study was to isolate, screen and identify lactic acid bacteria from different sources. As well, evaluate the more potent lactic acid bacteria isolates for their probiotic characteristics. Ninety-six bacterial isolates were isolated from different 18 sources, 51 (53%) isolates were able to hydrolyze 0.5% bile salts while 28 isolates were able to hydrolyze 1% bile salts. Also, only 11 isolates were able to tolerate 2% bile salts after 6h incubation periods. On the other hand, lactic acid bacteria isolates were able to survive at pH 1.5 and 3.0 as well 8.0. Also, these isolates were potent for cholesterol assimilation, NaCl tolerance, exopolysaccharides production, antioxidant activity. Lactic acid bacteria isolate MS87 that exhibited excellent probiotic characteristics was identified using 16S rRNA sequence as Pediococcus pentosaceus. This study led to suggest that environmental-derived lactic acid bacteria-strains could be used as a potential source of probiotic.