Cytotoxic effects of different lactic acid bacteria on Caco-2 cell

An example of a functional food, which has been the focus of intenseresearch activity in recent years, is probiotics ? `live microbial feed supplementswhich beneficially affect the host animal by improving its intestinal microbialbalance?. Most probiotic microorganisms belong to Lactic Acid Bacteria (LAB),such as Lactobacillus sp, Bifidobacterium sp and Enterococcus sp. The list ofhealthful effects attributed to probiotic bacteria is extensive; one of the theseeffects is their anticancer effects. The vast majority of studies on the anticancereffects deal with colorectal cancer (CRC), although there are some studies onbreast and bladder cancer. Colorectal cancer is one of the leading causes of cancermorbidity and mortality in western countries. The precise mechanisms by whichLAB may inhibit colon cancer are presently unknown.In this thesis, cytotoxic effects of cell-free filtrate and cell-free lyophilizedfiltrate of three lactic acid bacteria (Pediococcus pentosaceus, Lactobacillusplantarum, Weissella confusa) were studied on human colon adenocarcinomacells (Caco-2) by MTT Assay (tetrazolium assay). To determine this cytotoxiceffect, both cell-free filtrate and cell-free lyophilized filtrate were applied onCaco-2 cells at different concentrations and incubation timesIn this study, we determined that cell-free filtrate and cell-free lyophilizedfiltrate of three bacteria exerted different effects on Caco-2 cell viabilitydepending on time and dose-dependent. Data from obtained statistical resultsrevealed that maximum dose of cell-free filtrate of Lactobacillus plantarum(500?L/mL) were the most efficient bacteria on Caco-2 cell viability at 24hincubation.Keywords: Probiotics, Lactic acid bacteria, cell-free filtrate, cell-free lyophilizedfiltrate, Caco-2 cells, MTT assay.