酶的提取及其催化活性研究

[目的]酪氨酸酶是一种多酚氧化酶，具有广泛用途，因此对酪氨酸酶的研究受到广泛重视。[方法]试验以 pH=7.2的 Na2HPO4-HCl缓冲溶液为体系，用分光光度计在480nm处测定土豆提取液的吸光度，以吸光度对时间的变化率(ΔA/Δt)为反应速率，建立多巴溶液的转换动力学曲线，从而可计算出酪氨酸酶的活性。[结果]结果显示在此波长下，以 pH=7.2的Na2HPO4-HCl缓冲溶液为体系，对测定体系干扰小，所测数据波动小，酪氨酸酶的活性稳定性高，为进一步确定和研究影响酪氨酸酶活性的因素提供理论依据。[结论]该试验以缓冲溶液为底物研究和测定酪氨酸酶的催化活性，准确度高，效果佳。

Study on Extraction and Catalytic Activity of Tyrosinase

Objective] Tyrosinase is a kind of polyphenol oxidase used widely, and the study of tyrosinase attracts extensive attention. [Method] ln this experiment, A conversion kinetic curve of dopa solution was obtained using absorbance of potato extract at 480 nm in Na2HPO4-HCl buffer system at a pH value of 7.2 with the vari-ation rate of absorbance against time (ΔA/Δt) as reaction rate, and the activity of tyrosinase could thus be calculated. [Result] The results showed that at the wave-length, in the Na2HPO4-HCl buffer system with a pH value at 7.2, there was little in-terference to the system, the data showed smal fluctuations, and the activity of ty-rosinase was high and stable, further providing a theoretical foundation for the de-termination and study of factors influencing tyrosinase activity. [Conclusion] The catalytic activity of tyrosinase was studied and determined with buffer solution as substrate with high accuracy and good effect.