Screening for Antiproliferative Effect of Lactobacillus Strains Against Colon Cancer HT-29 Cells

摘要

One hundred and forty lactobacillus strains which were obtained from infant faces and traditional fermented foods in western China were examined for possible use as probiotics. The live whole cells from lactobacilli were tested for antiproliferative effects, adherent capability, acid and bile tolerance on colon cancer HT-29 cells. The results showed that eleven strains inhibited growth of HT-29 cells. Among the eleven strains, ten strains were further screened out through adhering activity assay. All the ten strains could grow in acidified broth at pH 1.5 and in 0.3% (w/v) bile salt. Nevertheless, G5, X11, X12, M5, M23, K11 and K14 showed the most profound inhibitory activity against HT-29 cells. While Q12, SB27, X2 and M7 were poorly presented. 16S rRNA gene sequences indicated that X12, M5, M7 and M23 were Lactobacillus paracasei, G5, Q12, SB27, X2, X11 and K14 were Lactobacillus casei, K11 was Lactobacillus rhamnosus. Together, these results suggest G5, X11, X12, M5, M23, K11 and K14 to be good probiotic candidates and potential application in functional foods and health-associated products.