Study on Content Dynamic Changes of Three Water-soluble Flavonoids in Isodon Lophanthoides / 中国药师

ABSTRACT

Objective:To establish an HPLC method for the simultaneous determination of viceninⅡ, isoschaftoside and schafto-side in Isodon lophanthoides, and analyze their content dynamic changes. Methods:The HPLC system consisted of a Phenomenex luna C18(250 mm ×4.6 mm, 5 μm)column and a solution system of methanol and 0.5% formic acid with gradient elution, the flow rate was 0. 8 ml·min-1 and the detection wavelength was 334 nm at the column temperature of 25℃and the injection volume was 10 μl. Results:The linear range of viceninⅡ, isoschaftoside and schaftoside was 0.130-3.110 μg(r =0.999 8), 0.180-4.540 μg(r =0.999 9) and 0.080-1.970 μg(r =0. 9999), respectively. The average recovery was 96.8% (RSD =1.9%), 99.2% (RSD =1. 6%) and 97. 1% (RSD=1. 6%) (n=6), respectively. The above three kinds of water-soluble flavonoids from seedling stage to significant accumulation, isoschaftoside and schaftoside reached the highest value in March and August, the content of VitexinⅡ in January and April tends to be stable, in May began to increase gradually, reached the maximum value in August, then began to de-crease. Conclusion:With the contents of water-soluble flavonoids as the indicators, the best harvest time of Isodon lophanthoides is March and August, and the quality of the medicinal materials harvested in August is the best.