双酶水解-DNS比色法测定白卡纸中淀粉含量的研究

Determination of Starch in White Card Paper by Double Enzymolysis-DNS Colorimetric Method

关键词:  白卡纸  淀粉  α-淀粉酶  糖化酶  测定

Key Words:white card paper  starch  α-amylase  glucoamylase  determination

摘要:为测定白卡纸中的淀粉含量，本研究选用α-淀粉酶和糖化酶对白卡纸进行双酶协同降解，采用3,5-二硝基水杨酸（DNS）比色法对酶解产物葡萄糖进行测定，进而计算白卡纸中的淀粉含量。在单因素实验分析研究的基础上，采用响应面分析法优化双酶水解-DNS比色法测定淀粉含量的最佳条件，建立数学模型，回归方程失拟误差不显著（P<0.000 1），理论值与测定值吻合（R²为0.988 6）；双酶水解-DNS比色法测定淀粉含量的最佳条件为：双酶添加量5 mg/mL，酶解时间75 min，酶解温度40 ℃。对该方法进行精密度和加标回收率测试，相对标准偏差为0.8%，加标回收率为96.2%~98.0%。

Abstract:To determine the starch content in white card paper， Glucoamylase and α-amylase were used to degrade the starch synergistically. Glucose of the enzyme hydrolysis product in the solution was measured by 3，5-dinitrosalicylic acid colorimetry （DNS） colorimetry and the starch content in white card paper was calculated. Based on the single factor experiment， response surface method was carried out to investigate the effects of key parameters， and the quadratic term model was established. The results of regression analysis presented a non-significant lack of fit （P<0.000 1） and a high coefficient of determination value （R²=0.988 6） for the response surface model. The optimum determination conditions of starch using double enzymolysis-DNS colorimetry were double enzyme addition amount of 5 mg/mL， enzymatic time of 75 min， enzymatic temperature of 40 ℃. The relative standard deviations and standard recovery of the method were 0.8% and 96.2%~98.0%， respectively.