The main object of the current work was to determine the antifungal efficiency of secondary metabolites product called synephrine that extracted from Citrus sinesis peels and the ability of synephrine to biosynthesis gold nanoparticles from HAucl4 which consider environmentally favourable method, then determine their activity against pathogenic human dermatophyte. The identification of synephrine done by Thin layer chromatography (TLC), High Performance Liquid Chromatography (HPLC) and The Fourier Transform Infrared (FTIR). The characterization of gold nanoparticles by using Ultra Violet-Visible Spectroscopy (UV-Vis), Field – Emission Scanning Electron Microscopy (FESEM) and Fourier Transform Infrared (FTIR), confirmed the biosynthesis of gold nanoparticles in diameter and morphology for AuNps biosynthesis by C. sinensis was 9.7-31 (nm) rounded to oval shape. The synephrine and AuNps that formed use it against some dermatophytes Trichophyton mentographytes, Trichophyton rubrum and Microsporum canis, the activity of synephrine against T. mentographytes at (10, 15 and 20 mg/mL) give less inhibition effect as compare with antifungal effect, while M. canis in 15 mg/mL show best effect than antifungal and for gold nanoparticles most concentration effective was (20 mg/mL).
