Myricetin

The myricetin was obtained from Macklin Inc. (Shanghai, China) with a minimum purity of 97%.

Vero-E6 or Huh-7 cells were seeded in a 96-well plate at a density of 20,000 cells/well and incubated at 37 °C in 5% CO₂ for 24 h. After that, different concentrations of myricetin (Macklin Inc., Shanghai, China) ranging from 15.63 to 1000 μM were added into individual wells, and the cells were further incubated for 72 h. Control wells were treated with medium alone. Cell viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-h-tetrazolium bromide (MTT) assay. Briefly, 10 μl of MTT solution (Cat # A600799-0001; Sangon Biotech, Shanghai, China) was added to each well and incubated for an additional 4 h. The medium was then removed, and 150 μl of methyl sulfoxide (DMSO) was added to each well. The absorbance (A) of each well was measured at 490 nm using a microplate reader. The cell viability of myricetin in Vero-E6 or Huh-7 cells was calculated as 100% × (A _myricetin – A _control)/A _control. The concentration of myricetin that reduced cell viability by 50% in Vero-E6 or Huh-7 cells was assessed by 50% cytotoxic concentration (CC₅₀). Meanwhile, the cytotoxicity of myricetin was also assessed in HEK293, THP1, or A549 cells using the MTT assay with concentrations ranging from 3.13 to 400 μM and stimulation for 24 h.