pH示差法测定紫荚豌豆中花青素条件的优化

Optimization of Analytical Condition of Determining Anthocyanin Content in Purple Pea by pH-Differential Method

紫荚豌豆因其富含花青素而具有更好的商品性,而截至目前在豌豆上花青素测定方法尚不明确。为确定pH示差法测定紫荚豌豆花青素的最佳测定条件,以紫荚豌豆品种‘ST16-18’为试材,经有机溶剂萃取、超声波处理后,对pH示差法测定紫荚豌豆中花青素的最佳测定波长、缓冲液pH值、反应的平衡温度和时间等条件进行优化,并进行加标回收率试验已验证优化结果。试验结果表明,在波长520 nm,缓冲液pH=1.0和pH=4.5的条件下,于30℃下恒温水浴60 min后测定紫荚豌豆中花青素的含量为最佳条件。紫荚豌豆品种‘ST16-18’中花青素的平均含量为1.972 mg·g^(-1),该方法的相对标准偏差(RSD)为1.526%,加标回收率为98.68%~99.75%。综上,采用优化后的pH示差法测得的紫荚豌豆中花青素总含量数据重复性好,可以为紫荚豌豆中花青素定量分析及品种选育提供参考。

Purple pea has better commercial value as it is rich in anthocyanin,but until now the method fordetermining anthocyanin in peas is not clear.In order to seek out the best condition to determine anthocyanin content in purple pea by pH differential method,purple pea'ST16-18'was used as the raw material,after the organic solvent extraction and ultrasonic treatment,the optimal determination wavelength,buffer pH value,reaction equilibrium temperature and time and other conditions was optimized,under this condition,the optimized results were verified by standard recovery experiments.The results showed that the best wave length was 520 nm,the pH of buffer solutions were 1.0 and 4.5 and maintained at 30℃for 60 min.The highest content of anthocyanin in purple pea variety was 1.972 mg·g^(-1),the relative standard deviation(RSD)of this method was 1.526%,and recoveries of the spiking samples were between 98.68%and 99.75%.In conclusion,the optimized pH differential method was used to measure the total anthocyanin content of purple peas with high repeatability,which provided a reference for the application of pH differential method to the determination of anthocyanins in peas.