Apoptotic and Antifungal Effects of Lactobacillus paracasei Postbiotics on HepG2 Cells Against Candida spp.

Aim: This study aimed to evaluate the antiproliferative effects of postbiotics derived from Lactobacillus paracasei subsp.paracasei (L.paracasei) on the HepG2 cell line and their antifungal activity against Candida species. Materials and Methods:Cell-free supernatants (CFS) were obtained from L. paracasei isolates, and their cytotoxic effects on HepG2 cell lines were assessed using the MTT assay.Fluorescent staining and cell cycle analyses were performed on the cells at the determined inhibitory concentration 50 (IC 50 ).The antifungal activities of the postbiotics were evaluated by determining the minimum IC 50 and minimum fungicidal concentration values on Candida albicans (C.albicans) ATCC 90028 and Candida glabrata (C.glabrata) ATCC 2950 strains.Results: Live and heat-inactivated L. paracasei CFS were found to exhibit significant cytotoxic effects on HepG2 cells.Inactivated CFS produced stronger antiproliferative effect with lower IC 50 value (live: 20.13%; inactive: 10.81% ± standard deviation).Acridine orange/propidium iodide staining revealed an increase in apoptotic cells, while cell cycle analysis revealed a significant increase in the Sub-G phase (control 0.67%; live CFS 6.47%; inactivated CFS 12.67%).In antifungal tests, both CFS strains were found to be effective against C. albicans and C. glabrata.While inactivated CFS (6.25%) was more potent in C. albicans, live CFS (12.5%) was found to be more effective in C. glabrata.Conclusion: This study demonstrates that L. paracasei CFSs possess anticancer and antifungal effects.The fact that these effects vary depending on the CFS form and target yeast species suggests that the postbiotic response is biologically driven and specific.Elucidating the active components of CFS will significantly contribute to the development of new postbiotic-based treatment strategies.