Determination of the Total Flavonoids in Different Sections of Rruncinate Knotweed Herb by Visible Spectrophotometry

The sample solution was prepared by the method of ultrasonic extraction with 70% Ethanol solution at 30 ℃ for 40 min,of which the total flavonids were determined,with the method of visible spectrophotometry at 510 nm in runcinate knotweed herb with rutin as the standard sample,NaNO2,Al(NO3)3 and NaOH as the color agent.The result showed that a good linear relationship between 0.008 and 0.040mg/mL,the regression equation was A=9.5786C+0.0068,with the correlation coefficient R2= 0.9987.The content of total flavonoids in runcinate knotweed herb from roots was 60.17 mg/g,the stalks was 28.07 mg/g,and the leaves was 49.73 mg/g(n=3),with the RSD value of 1.75%,2.83% and 2.19% respectively.Conclusively,the highest content of total flavonoids was in the runcinate knotweed herb roots,and the lowest was in the leaves.