Assessment and identification of cholesterol-degrading probiotics

This study aimed to isolate and identify probiotic Lactobacillus and evaluate their effects on cholesterol levels. Probiotic Lactobacillus was isolated from three samples butter, milk, spinach and egg yolk. MRS agar and MRS broth were used for the growth of Lactobacillus and identification of Lactobacillus were confirmed by gram staining and various biochemical tests. Growth and survival of Lactobacillus was evaluated by antibiotic resistance, acid tolerance in various Ph (4, 7 & 9), Bile salt tolerance under different concentrations of bile salt (such as 0.1g, 0.2g, 0.3g, 0.4g and 0.5g) and in various temperatures such as (37℃, 50℃& 4℃). Cholesterol degradation capability of Lactobacillus was determined under three different concentrations of cholesterol (200μg/ml, 400μg/ml, and 600μg/ml). The results of cholesterol assimilation were recorded by the percentage of cholesterol degraded. Out of all three samples, Lactobacillus isolated from butter, milk showed the highest cholesterol degradation (26.68%) at concentration 600μg/ml. The present study showed that the isolated probiotic LAB was able to assimilate cholesterol which in turn can reduce the risk of cardiovascular diseases. (author)