Cholesterol reduction mechanisms and fatty acid composition of cellular membranes of probiotic Lactobacilli and Bifidobacteria

The cholesterol removal by 14 strains of lactobacilli and bifidobacteria was investigated by measuring the residual cholesterol in de Mann, Rogosa, Sharpe (MRS) broth supplemented with cholesterol. The ability of probiotics to deconjugate bile salts was examined using BSH activity and LA2400 and BL5022 were found to liberate significantly more cholic acid than other probiotic strains. Amongst the selected probiotic strains, BL5022, LA2404, LA2410 and BB5286 demonstrated the highest cholesterol removal ability. The cholesterol assimilation by growing cells was significantly higher than the resting and dead cells. Significant changes were observed in the fatty acid composition of the cellular membranes of all probiotics incubated in presence of cholesterol, thus indicating cholesterol removal by adsorption or absorption. This study confirmed the suitability of BL5022, LA2404, and LA2410 strains for application in functional food formulations especially where cholesterol reduction in food is needed.