室温下5分钟快速测定玉米中的蛋白质

依据玉米醇溶蛋白质溶于90%～93%乙醇的特性,在室温下采用90%乙醇做玉米蛋白质的抽提剂,用碱性硫酸铜显色,在550nm处测定吸光度。本文研究了该体系的最佳反应条件,成功地建立了一个玉米蛋白质快速测定的新方法。结果表明:①与其他快速方法相比,该方法不用加热、不用离心、不用抽滤,操作简便快速,经济安全。②该方法精密度高(RSD为0.38%),结果准确,与国标凯氏法基本一致,回收率为97.0%～101%。

At Room-temperature in 5 Minutes, A Rapid Method for the Determinaion of Protein in Corn

According to the characteristics that protein in corn is soluble in alcohol (90%～93%). The protein in corn was extracted with alcohol (90%) and coloured with basic solution of CuSO4 the absorbance was measured at 550nm. The optimum reaction of protein in the system was studied and a new rapid method, at room-temperature, for determining protein in corn was developed. The results showed two facts: ①The method needs no heating, centrifuging or suction and the test is simple and rapid, economical and safe in comparison with other rapid methods. ②The method has a high precision (RSD 0.38%), and fair reclamation (97.0%～101%). The results obtained by this method agree well with those obtained by the kjeldahl method.