Inhibition of Tyrosinase by Yak Collagen Peptides

XIE Sha; LU Haili; HUANG Qi; HUANG Meigui; BI Xiufang; CAI Yinchuan; HAO Gang

doi:10.13982/j.mfst.1673-9078.2025.10.1068

Abstract：To investigate the inhibition mode of the yak bone collagen peptide fraction,YBCP-2-2,its antioxidant activity,Cu2+chelating capacity,inhibition kinetics against tyrosine mono-and di-phenolase,and interaction with tyrosinase were analyzed using fluorescence spectroscopy.The results demonstrated that YBCP-2-2 exhibited notable antioxidant capacity,with IC50 values of 6.02 mg/mL and 0.81 mg/mL for scavenging DPPH and ABTS free radicals,respectively.YBCP-2-2 also exhibited a total reducing power absorbance value of 0.57 at 8.00 mg/mL,along with superior Cu2+chelating capacity,with an IC50 of 3.22 mg/mL.Furthermore,YBCP-2-2 substantially inhibited tyrosine monophenolase in a mass concentration-dependent manner.At an inhibitor mass concentration of 20.00 mg/mL,the initial velocity of the reaction decreased from 0.012/min to 0.003 9/min.The inhibition type on tyrosine diphenolase was identified as mixed competitive inhibition,with both Vmax and Km undergoing changes in response to variations in the collagen peptide mass concentration;the inhibition constant KI was determined as 0.58 mg/mL.The interaction between YBCP-2-2 and tyrosinase induced fluorescence quenching of the enzyme,accompanied by a red-shift in the fluorescence emission spectrum from 340.20 nm to 351.60 nm.These findings conclusively demonstrate the potent tyrosinase inhibitory activity of collagen peptides,thereby providing a theoretical foundation for further investigations into peptide-based tyrosinase inhibition.