Quality evaluation of twelve species of Chinese Ephedra (ma huang)
Zhang, J.S.; Tian, Z.; Lou, Z.C.
Yao Xue Xue Bao 24(11): 865-871
1989
ISSN/ISBN: 0513-4870 PMID: 2618686 Document Number: 327417
The contents of six Ephedra alkaloids, namely ephedrine, pseudoephedrine, norephedrine, methylephedrine and methyl-pseudoephedrine, in 12 species of Chinese Ephedra collected in 24 districts were determined by high performance liquid chromatography (HPLC). Zorbax CN column (25 cm .times. 4.6 mm I.D.) was used and the temperature of column oven was 23 .apprx. 25.degree. C. Dibutylamine phosphate solution 0.0009 mol/L (pH 2.2) was used as the mobile phase at flow rates: 0.8 ml/min for the first 7 minutes, raised to 1.5 ml/min in 30 sec and maintained for 16 minutes. The alkaloids eluted were detected at wavelength 210 nm. The results showed that ephedrine and pseudoephedrine are the main components in these Ephedra herbs, but the contents of the six Ephedra alkaloids vary greatly with the plant species. The contents of total alkaloids are higher and ephedrine is the main component in samples derived from E. sinica, E. equisetina, E. monosperma and E. intermedia var. tibetica; but in E. intermedia and E. lomatolepis, the content of pseudoephedrine is higher than that of ephedrine. Methylephedrine content is higher in E. intermedia var. tibetica produced in Xizang (Tibet) and in E. sinica produced in northeastern China than that in other species. The results also showed that the samples derived from E. przewalskii and E. lepidosperma contain so little alkaloids (< 0.1%) that they are considered not suitable to be used as the drug Ma Huang. It is of interest that the cultivated E. sinica showed lower alkaloids content compared with that growing wild.