Selection of probiotic lactic acid bacteria isolated from fermented plant beverages.

Screening for probiotic bacteria from non-human sources were performed in this study. Three hundred and twenty-seven strains of Lactic Acid Bacteria (LAB) were isolated from 90 samples of Fermented Plant Beverages (FPBs) and pickles collected from around Thailand. Potentially useful probiotic properties were investigated in vitro in parallel with a commercial probiotic strain of Lactobacillus casei, R obtained from a dairy probiotic product in Thailand. An isolate SS2, selected from a fermented star fruit beverage, survived in the human biological barriers (0.15 and 0.30% bile salt, pH values between 3-8, presence or absence of oxygen), resistance to some antibiotics in general use and showed other benefits to the host (antibacterial activity, utilizations of protein and starch). The isolate SS2 had a higher specific growth rate and better inhibitory properties against food borne pathogenic bacteria and spoilage organisms than the commercial probiotic R strain. It also grew well in MRS and the SPY2 medium that is free from animal-derived ingredients, (r>0.8). The isolate SS2 was therefore considered to be a potentially useful probiotic LAB for a non dairy product such as FPBs and was provisionally identified as a strain of Lactobacillus plantarum.