Comparison of lactobacilli isolated from Chinese suan-tsai and koumiss for their probiotic and functional properties

• Lactobacilli from koumiss showed greater bile tolerance than those from suan-tsai.
• Lactobacilli from koumiss are more adhesive to HT-29 cells than those from suan-tsai.
• Lactobacilli from koumiss remove more cholesterol in vitro than those from suan-tsai.
• BSH-positive lactobacilli are more common in koumiss than in suan-tsai.
• Cell-free extracts of lactobacilli are stronger antioxidants than their intact cells.

Suan-tsai and koumiss are traditional Chinese fermented foods. This study compared the dominant lactobacilli in suan-tsai and koumiss for their probiotic properties, cholesterol-lowering potentials and antioxidant activities. Thirty Lactobacillus strains were isolated from eight homemade suan-tsai samples (8 Lactobacillus plantarum and 6 Lactobacillus brevis) and seven homemade koumiss samples (7 Lactobacillus helveticus, 5 Lactobacillus acidophilus, 2 L. plantarum and 2 Lactobacillus casei), and they were subsequently analyzed for the above parameters. No significant differences were found between the mean antioxidant activities of the lactobacilli isolated from koumiss and suan-tsai, whereas the lactobacilli isolated from koumiss exhibited higher mean bile tolerance, adhesion to HT-29 cells, cholesterol removal and percentage of bile salt hydrolase-positive strains than did those isolated from the suan-tsai samples. Thus, koumiss could be considered a better source of potential probiotics, especially cholesterol-lowering probiotics, than suan-tsai.