Utilization of lactobacilli extracts as antibacterial agent and to induce colorectal cancer cells apoptosis: Application in white soft cheese

Abstract

Food-borne illnesses certainly increase the risk of developing colon cancer. Due to the de-functionalization of the gut microbiota and host-microbe interactions caused by the preponderance of infectious pathogens, sensitive host cells are more likely to develop mutations. The current research utilized some bio-protective lactobacilli to clarify the metabolic basis of human GIT protection from both anti-pathogenic and anti-cancer views. Both cells and methanolic extracts of Lactoplantibacillus plantarum (LP), Lactobacillus acidophilus (AC), and Lactobacillus rhamnosus GG (GG) were evaluated. The extracts were evaluated for their components by Liquid chromatography–mass spectrometry (LC–MS). The antimicrobial activity of all extracts was determined. A Lactobacillus acidophilus-based extract had the greatest zones of inhibition against all indicator pathogens. Upon co-culturing with pathogens, Lactoplantibacillus plantarum (LP) achieved the maximum reduction percentage of all pathogenic populations. Further LC/MS-based metabolic profiling of extracts showed various biologically active compounds that are thought to be the key health-promoting agents. It was noticed that the IC50 values of HCT 116 cell line upon AC, GG, and LP treatments were 65.897 μg/mL, 79.139 μg/mL, and 71.681 μg/mL, respectively when compared by Raloxifene (RX). Lactobacillus acidophilus (AC) recorded the lowest IC50 (52.053 g/mL) and the highest cytotoxic fold change in Caco-2 cells. Generally, all lactobacilli extracts induced Caco-2 cell apoptosis in a sensitive manner compared to HCT 116 cells by inhibiting cancerous proliferation and inducing nitric oxide release. When various Lactobacilli strains were applied in-situ to white soft cheese, Lactobacillus acidophilus (AC) demonstrated no growth for either bacterial pathogens or spoilage fungi towards the end of the storage time.