Study on Content Determination of Coumarin in Fraxini Cortex Extract / 中国中医药信息杂志

ABSTRACT

Objective To establish a UV spectrophotometry method and an HPLC method respectively for the determination of the total content of coumarin and contents of four main constituents of coumarin in Fraxini Cortex extract.Methods UV spectrophotometry was used for the determination of the content of total coumarin in Fraxini Cortex extract. The reference substance was Aesculin, and the maximum ultraviolet absorption wavelength was 334 nm. The HPLC method was used to determine the contents of Aesculin, Fraxin, Aesculetin and Fraxetin in Fraxini Cortex extract, using gradient elution with acetonitrile-phosphate solution (0.01%) as mobile phase on Agilent ZORBAX SB-C18 chromatographic column (4.6 mm × 250 mm, 5μm) at room temperature.Results For the UV method, the linear range of the mass concentration of Aesculin was 5.76-23.04μg/mL (r=0.999 9), and the average recovery was 100.6% (RSD=1.8%). For the HPLC method, the linear ranges of the mass of Aesculin, Fraxin, Aesculetin and Fraxetin were 0.055 0-3.850 0μg (r=0.9997), 0.053 9-3.773 0μg (r=0.999 8), 0.060 0-0.660 0μg (r=0.999 9), and 0.056 2-0.618 2μg (r=0.999 9), respectively, and the average recoveries were 96.97% (RSD=1.26%), 100.80% (RSD=2.22%), 99.04% (RSD=2.47%), and 98.77% (RSD=1.94%), respectively.Conclusion Both of the two methods are simple, accurate and reliable, and can be used for the quality control of total coumarin and the main constituents of coumarin in Fraxini Cortex extract.