Effect Of Maize Monomer Peptide TPM On Tyrosinase Activity

With the continuous abstract improvement of the social and economic and cultural levels,more and more women begin to pay attention to skin care and beauty.At present,the demand for whitening cosmetics is increasing,so finding effective and low toxicity whitening products has become the research hotspot of many researchers.Melanin,which exists in animal and plant cells,is the main cause of pigment deposition on skin surface,and its synthesis is regulated by tyrosinase,which is the key enzyme of melanin synthesis and regulated by corresponding inhibitors.Therefore,appropriate tyrosinase inhibitors will play a crucial role in the synthesis of melanin.At present,many whitening products on the market are artificially synthesized,the side effects of these products are not yet clear.It is necessary to find natural,low toxic whitening products.Several active peptides were analyzed in our laboratory.It was found that the activity tetrapeptide?TPM?obtained from the purification and extraction of corn protease had a very good effect on the inhibition of tyrosinase and oxidation resistance.In this study,we studied the role of TPM on tyrosinase inhibition kinetics by biochemical experiments in vitro with TPM as the research object.Molecular docking experiments simulated the amino acid sites of the interaction between tyrosinase and TPM.At the same time,TPM was used to treat murine melanoma B16-F10 cells in morphology,cell value added rate,tyrosinase activity and melanin production,We use the HUVEC cells to Study on antioxidation.1?Detection of tyrosinase inhibition by TPM by enzyme labeling method,Under the condition of pH 6.8,tyrosine was used as substrate and the reaction system was established at 37?.The inhibitory effect of TPM on tyrosinase was dependent on the concentration of tyrosinase.When the inhibition rate was 50%,the IC₅₀ value of TPM semi-inhibitory concentration was 1.11 mM.2?The binding mode between TPM and tyrosinase was studied by Autodock software.It was found that Gln 41,Glu 173,Glu 173 and Asn 174 were found in TPM and tyrosinase.The hydrogen bond of amino acids such as Lys 180 and His 182 have a binding energy of-0.9 Kcal/mol with TPM and tyrosinase.3?The influence of different concentrations of TPM on the morphology of mouse melanoma cells was observed by inverted microscope.The effect of TPM on cell proliferation was observed by MTT assay.The effect of TPM on tyrosinase activity in B16-F10 cells was detected by L-dopa oxidation method.The effect of TPM on cytomelanin production was studied by sodium hydroxide cleavage.The results showed that TPM could inhibit melanogenesis by inhibiting the activity of tyrosinase in cells.The toxicity of arbutin to cells was less than that of arbutin at the same concentration.4?Human umbilical vein epithelial cells?HUVEC?were damaged by H₂O₂ to detect the antioxidation of TPM and arbutin.The survival rate of HUVEC treated with H₂O₂ alone was 51.1%.When the concentration of TPM was 900?g/ml,the cell survival rate was 90.8%.the cell survival rate was concentration-dependent.The content of ROS in cells showed that the content of ROS in H₂O₂ group was only 1.49times that of 900?g/mL TPM.TPM significantly reduced the intracellular free radical concentration.The scavenging effect of free radicals was more obvious with the increase of TPM concentration.