Materials
S1. The isolation and purification of MG from n-butanol fraction of
Camellia nitidissima Chi flowersThe n-butanol fraction of C. nitidissima Chi flowers was obtained following our previous study [1]. Then n-butanol fraction was repeatedly separated into different column chromatography such as silica gel, Sephadex LH-20, and C18 reversed silica gel, to obtain MG (48 mg). The structure of the compound was determined by its physicochemical and spectral data ( 1 H-NMR, 13 C-NMR, and ESI-MS, S3) which were in agreement with those reported in the literature [2]. The isolated MG was dissolved in DMSO to prepare a stock solution of 100 mg/mL.