Extraction Technology of Total Flavonoids in Uighur Medicine Brassica rapa L.by Orthogonal Test

The optimum extraction conditions of total flavonoids in Brassica rapa L.were explored.With ethanol as solvent,the content of total flavonoids in Brassica rapa L.was determined by UV-Vis spectrophotometry combined with Soxhlet extraction,and the reliability and repeatability of the method were tested through the stability,precision and recovery experiments.The results showed that both the standard solution and the test solution had the maximum absorption at 510nm.The regression equation was A = 0.02054C + 0.07628,r=0.9998(0—24μg·mL~(-1)).The optimized extraction conditions were as follows:75%ethanol of 30 ratio of liquid to material,extraction time of 120min.The average content of total flavonoids was 2.805%,and the average recovery was 100.88%,RSDs of precision and recoveries were 0.46%and 2.26%,respectively.The method has simple operation,high sensitivity and accurate results,that can be applied to the determination of total flavonoids in Brassica rapa L..