Antimicrobial and healing efficacy of bile salts with insights into cytotoxic activity

Bile salts play crucial roles in lipid digestion and metabolism, with emerging evidence suggesting their involvement in cell signaling, wound healing, and potential antimicrobial activities. The analysis of bile salts revealed diverse compounds, including fatty acids, methyl esters, glycerol, flavonoids and steroidal derivatives. These findings suggest that the identified compounds are byproducts of lipid metabolism and may reflect dietary influences within the sample. Bile salts demonstrated significant antimicrobial activity against resistant and common pathogens. Against MRSA, they produced an inhibition zone of 22 ± 0.33 mm, surpassing the standard (18 ± 0.8 mm), indicating strong efficacy. For S. aureus and S. epidermidis, bile salts showed robust inhibition zones of 28 ± 1.25 mm and 29 ± 1.66 mm, respectively, exceeding the activity of the reference standard. Additionally, bile salts exhibited effective antifungal activity against C. albicans, C. tropicalis, and C. glabrata, with zones of 23 to 28 mm. According to the MIC and MBC/MFC results, bile salts were more effective against S. aureus and MRSA than S. epidermidis, C. glabrata was the most resistant among the tested Candida species. Bile salts significantly enhanced HFB4 cell migration and wound closure over 48 h, showing a 57.58% closure compared to 31.23% in the control group, indicating their potential to promote healing. However, bile salts exhibited dose-dependent cytotoxicity on Vero cells (CCL-81) and A-431 cells (IC₅₀ ≈ 74 µg/mL). The similar IC₅₀ values indicate low selectivity and a limited therapeutic window, which constrains their anticancer potential at the current stage of investigation. The cell cycle analysis of A-431 human epidermoid carcinoma cells demonstrated that treatment with bile salts induced significant cell cycle arrest at the G2/M phase. Compared to the control group, which showed the majority of cells in the G0/G1 phase (82.04%), bile salt-treated cells exhibited a marked increase in the G2/M population (from 0.81 to 8.63%). These findings highlight the multifaceted bioactivity of bile salts and underscore their relevance in both antimicrobial and anticancer research. Given their broad-spectrum efficacy and bioactive profile, bile salts represent a promising candidate for further therapeutic development and clinical investigation.