Dual Assessment of Cytotoxicity Induced by Lactobacillus Acidophilus Cell-Free Supernatant, Gold Nanoparticles, and Their Combination in MDA-MB-231 and Rat Embryonic Fibroblast Cell Lines

Breast cancer is a severe global health issue, having a high fatality rate worldwide. Because conventional cancer therapy is linked to tumour spread, drug resistance, and chemotherapy side effects, researchers should look into non-traditional methods. One intriguing strategy to deal with this issue is using nanoparticles and natural compounds like Lactobacillus metabolites as possible cancer treatments. Here, we tested the cytotoxicity of Lactobacillus cell-free supernatant (CFS), gold nanoparticles (AuNPs), and their combination against two cell lines MDA-MB-231 and Rat Embryonic Fibroblasts (REF) using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and percentage of cell viability was recorded. Results showed a synergistic impact of the combination on MDA-MB-231 cells when the IC50 recorded was 70 µg/ml compared to treatments of CFS and AuNps alone when the IC50 recorded were 187 and 196 µg/ml respectively. On rat embryonic fibroblasts (REF) CFS displayed the most cytotoxic impact with IC50 equal to 115 µg/ml followed by combination treatment (IC50 = 693 µg/ml) and then by AuNPs with recorded IC50 of 895 µg/ml. In summary, we demonstrated that Lactobacillus cell-free supernatant, gold nanoparticles and their combination represent a promising candidate as anticancer agents. The cytotoxicity against breast cancer cell line was enhanced when the supernatant was combined with gold nanoparticles while the supernatant gave the best cytotoxic effect against REF cells.