The effect of melatonin on antifungal susceptibility in planktonic and biofilm forms ofCandidastrains isolated from clinical samples

Abstract

In recent years, the significant increase in the isolation of antifungal resistant Candida species in presence of biofilm, have made it necessary to develop alternative agents for the treatment of these infections. In this study, the effect of antifungal susceptibility of melatonin were investigated in planktonic and biofilm forms of Candida strains isolated from the clinical samples sent to our laboratory. Biofilm formation was determined by modified microplate method. In order to determine antifungal susceptibility in biofilm-forming strains, MIC was determined by broth microdilution method in planktonic form, and MBEC values by Calgary biofilm method in biofilm form. Susceptibility tests were repeated in the presence of melatonin. Antifungal susceptibility tests repeated with antifungals combined with melatonin showed a decrease in both MIC and MBEC values; melatonin was found to be more effective especially in planktonic forms. While the most effective combination was achieved with fluconazole in the planktonic form, no statistically significant difference was found between the combinations in biofilm form. As a result, melatonin was thought to be a new alternative in the treatment of Candida infections.

Potential utility of melatonin in deadly infectious diseases related to the overreaction of innate immune response and destructive inflammation: focus on COVID-19

“…Inflammation largely belongs to the innate immune response. Meanwhile, several studies have reported antiviral and antibacterial activities of melatonin in animals and in plants (50)(51)(52)(53). These reports are challenging with regard to the questions of whether and under which conditions melatonin enhances or suppresses the innate immunity in organisms.…”

Microbial production of beneficial indoleamines (serotonin and melatonin) with potential application to biotechnological products for human health

“…On the other hand, melatonin has been well-described as a coadjuvant treatment in several gut diseases by increasing the proliferation of immune cells and the antimicrobial activity of intestinal microorganisms (Xu et al 2019;Ma et al 2020). Besides, some authors have also reported the antibacterial and antifungal effects of melatonin (Kilinçel et al 2019;Xu et al 2019).…”

“…The antifungal property of melatonin, which was tested in experimental models using rats infected with Candida albicans, showed a reduction in the expression of interleukin-6 (Kilinçel et al 2019). Daryani et al (2018) described melatonin therapeutic effect in the treatment of parasitic infections mainly caused by parasitic protozoa, suggesting that melatonin enhances the host immune response in infections such as Chagas disease, amoebiasis, giardiasis, and malarial infections, among others.…”

“…Besides, some authors have also reported the antibacterial and antifungal effects of melatonin (Kilinçel et al . 2019; Xu et al . 2019).…”

“…The antifungal property of melatonin, which was tested in experimental models using rats infected with Candida albicans, showed a reduction in the expression of interleukin‐6 (Kilinçel et al . 2019). Daryani et al .…”