ABSTRACT
Objective:To establish an HPLC-ELSD method for the determination of mahuannin A in ephedrae radix et rhizoma. Methods:The content of mahuannin A was determined by an HPLC-ELSD method on an Alltima TM C18 column (250 mm × 4. 6 mm, 5 μm). The mobile phase was acetonitrile-water (28∶ 72) with a flow rate of 0. 7 ml·min-1, and the column temperature was 30℃. The temperature of drift tube heater was 105℃ and the flow rate of carrier gas was 2. 8 L·min-1 . Results:The linear range of mahua-nnin A was 42. 56-383. 04 μg·ml-1(r=0. 999 8). The average recovery and RSD was 99. 9% and 1. 96%(n=6), respectively. Conclusion:The method is simple and the result is accurate. It can be used for the quality control of ephedrae radix et rhizaoma.
ABSTRACT
Objective: To study the flavonoids from the roots of Ephedra sinica in Ephedra Tourn. ex L. Methods: The roots of E. sinica were extracted with 90% ethanol, and isolated and purified by silica gel, Sephadex LH-20, and RP-18 gel column chromatography. All the compounds were identified based on spectral analyses (including MS, 1H-NMR, and 13C-NMR). Results: Thirteen flavonoids were isolated from the roots of E. sinica and were characterized as ephedrannin A (1), mahuannin A (2), mahuannin B (3), mahuannin D (4), apigenin (5), kaempferol (6), quercetin (7), dihydroquercetin (8), 3′, 4′, 5, 7-tetrahydroxy flavanone (9), (+)-catechin (10), (-)-epi-catechin (11), afzelechin (12), and (-)-epi-afzelechin (13), respectively. Conclusion: Compounds 7-13 are obtained from this plant for the first time.