【摘要】 目的 制备环γ-聚谷氨酸，研究其美白活性。方法 以谷氨酸（Fmoc-Glu-OTBU）为原料，制备四元、八元和十元的环γ-聚谷氨酸（cyclo-γ-PGA），通过体外和细胞内实验，研究3种不同相对分子质量（M_r）的cyclo-γ-PGA的酪氨酸酶抑制活性。结果 测得3种产物四元cyclo-γ-PGA、八元cyclo-γ-PGA和十元cyclo-γ-PGA纯度分别为98.31%,95.29%,95.67%,M_r分别为516.39,1032.83,1291.28。以γ-PGA为对照品，3种不同M_r的cyclo-γ-PGA均具有不同程度的酪氨酸酶抑制活性，其中十元cyclo-γ-PGA酪氨酸酶活性在体外和细胞内均最强。结论 cyclo-γ-PGA具有美白活性，美白活性随着M_r的增大而增加，且在细胞内的特性表现更优异；cyclo-γ-PGA的美白活性要高于γ-PGA，为后续cyclo-γ-PGA用于皮肤美白和化妆品领域中提供理论基础。更多还原

【Abstract】 Objective To prepare cyclo-γ-polyglutamic acid （cyclo-γ-PGA） and study its whitening activity.Methods Three cyclo-γ-PGA of different relative molecular weights （M_r） were prepared using glutamic acid as the raw material.The tyrosinase inhibitory activity of three cyclo-γ-PGA of different M_r was investigated through in vitro and intracellular experiments.Results The purities of the three products of tetrapeptide cyclo-γ-PGA,octapeptide cyclo-γ-PGA and decapeptide cyclo-γ-PGA were 98.31%,95.29%and 95.67%,respectively,with M_r of 516.39,1032.83 and 1291.28.Using γ-PGA as the reference substance,three different M_r of cyclo-γ-PGA all exhibited varying degrees of tyrosinase inhibitory activity,and decapeptide cyclo-γ-PGA having the strongest tyrosinase inhibitory activity in vitro and in cells.Conclusion This study demonstrates that cyclo-γ-PGA has whitening activity,which increases with increasing M_r and exhibits superior intracellular characteristics.Based on the results of both in vitro and intracellular experiments,it has been concluded that cyclo-γ-PGA has a higher whitening activity than γ-PGA,providing a reference and theoretical basis for the subsequent use of cyclo-γ-PGA in the field of skin whitening and cosmetics.更多还原