紫外-可见分光光度法测定龙爪槐叶中总黄酮含量

目的建立龙爪槐叶中总黄酮质量控制的方法。方法龙爪槐叶粉碎后,置索氏提取器中,甲醇连续提取,低温放置24 h以上,过滤去除叶绿素及杂质,滤液即为提取液。以芦丁为标准,亚硝酸钠-硝酸铝-氢氧化钠显色,采用紫外-可见分光光度法测定总黄酮含量,测定波长为500 nm。结果芦丁的线性范围为8～48μg·ml-1,回归方程：A=10.7318 C-0.0514,r=0.9991,平均回收率为94.85%,RSD=1.84%。结论龙爪槐叶甲醇提取后直接测定总黄酮含量,方法简便,结果准确,可用于龙爪槐叶总黄酮的质量控制。

Determination of Levels of Total Flavonoids in Leaves of Sophora japonica by a Spectrometric Method

Objective To establish a method for quality control of the total flavonoids level in leaves of Sophora japonica f.pendula Loud.Arb.Brit.Methods The extractions of total flavonoids in leaves of Sophora japonica f.pendula Loud.Arb.Brit.were prepared by consecutive extraction with absolute methanol.Color was formed by mixing the extractions of total flavonoids with NaNO2-Al(NO3)3-NaOH solution.With authentic rutin as the standard,the color was determined using the wavelengths of 500 nm by a spectrometer.Results The linear range of rutin was between 8 μg · ml-1 and 48 μg · ml-1.The regression equation was A=10.7318C-0.0514 with a regression coefficient of 0.9991.The average recovery of the method was 94.85% with an RSD of 1.84%.Conclusion It is easy,highly accurate to determine the level of total flavonoids in leaves of Sophora japonica f.pendula Loud.Arb.Brit.by a spectrometric method,with which the quality of total flavonoids in leaves of Sophora japonica f.pendula Loud.Arb.Brit can be controlled easily.