Myricetin disturbs the cell wall integrity and increases the membrane permeability of.
J Microbiol Biotechnol. 2021 Nov 11 ;32(1). Epub 2021 Nov 11. PMID: 34750288
The fungal cell wall and membrane are the principal targets of antifungals. Herein, we report that myricetin exerts antifungal activity againstby damaging the cell wall integrity and notably enhancing the membrane permeability. In the presence of sorbitol, an osmotic protectant, the minimum inhibitory concentration (MIC) of myricetin againstincreased from 20 to 40 and 80 ?g/ml in 24 and 72 h, respectively, demonstrating that myricetin disturbs the cell wall integrity of. Fluorescence microscopic images showed the presence of propidium iodide-stainedcells, indicating the myricetin-induced initial damage of the cell membrane. The effects of myricetin on the membrane permeability ofcells were assessed using crystal violet-uptake and intracellular material-leakage assays. The percentage uptakes of crystal violet for myricetin-treatedcells at 1×, 2×, and 4× the MIC of myricetin were 36.5, 60.6, and 79.4%, respectively, while those for DMSO-treatedcells were 28.2, 28.9, and 29.7%, respectively. Additionally, myricetin-treatedcells showed notable DNA and protein leakage, compared with the DMSO-treated controls. Furthermore, treatment ofcells with 1× the MIC of myricetin showed a 17.2 and 28.0% reduction in the binding of the lipophilic probes diphenylhexatriene and Nile red, respectively, indicating that myricetin alters the lipid components or order in thecell membrane, leading to increased membrane permeability. Therefore, these data will provide insights into the pharmacological worth of myricetin as a prospective antifungal for treatinginfections.