Background: Probiotics have shown to reduce cancer recurrence and side effects in colorectal cancer patients.
Objective: To isolate the lactic acid bacteria from Thai healthy newborn feces and screen good probiotics with anticancer
properties.
Material and Method: Lactic acid bacteria were isolated from newborn feces and selected for the cytotoxicity property
against human cancer cell lines by MTT assay and probiotics property by acid and bile tolerance tests.
Results: Among 200 lactic acid bacteria isolated, 3 and 1 isolates significantly demonstrated strong and moderate antiproliferative effect against Caco-2 cells, respectively. Likewise, 4 and 5 isolates showed significant strong and moderate inhibitory effect on U937 cells, respectively. Seven candidate strains did not displayed cytotoxic to normal cells (Vero), except MSMC 112-2. All candidates showed good probiotics properties in resistance to acidic condition (pH 2-4) and to 1-4% bile concentrations, except MSMC105-3 showed intolerance at 4% bile concentration. The nucleotide sequence homology showed that MSMC95-4, MSMC104-2, MSMC111-2, MSMC112-2 and MSMC215-1 strains belong to Enterococcus faecalis (99.4%, 98.8%, 99.5%, 98.7 and 98.9%, respectively), MSMC105-3 is Lactobacillus salivarius (99.1%) and MSMC171-1 is Enterococcus faecium (99.3%).
Conclusion: The authors have isolated lactic acid bacteria which have anticancer and good probiotics properties.

Keywords: Lactic acid bacteria, Probiotics, Anticancer, Caco-2 cells, U937 cells