S. THAWEESANG AND B. LEENANON
Abstract
The middle of exponential phase and stationary phase cells of probiotic Lactobacillus acidophilus TISTR 1338 were used for investigation of sublethal and lethal levels of bile salt stress conditions. It was found that there was no significant difference between the two phases. MRS broth containing 0.2% (w/v) bile salt was chosen for a sublethal level while MRS broth containing 0.8% and 1% (w/v) bile salt were used to be a lethal level. The results also revealed that cells of Lactobacillus acidophilus TISTR 1338 adapted in 0.2% (w/v) bile salt for 5 hours and challenged in 0.8% bile salt for 1 hour had the highest percentage of survival and tolerance factor.