CHROMATOGRAPHY OF ERGOT ALKALOIDS Ⅰ.IDENTIFICATION OF ERGOT ALKALOIDS AND DETERMINATION OF ERGOMETRINE CONTENT IN CHINESE ERGOTS

The identification of alkaloids and the determination of ergometrine contents in several Chinese ergot samples have been accomplished by means of paper chromatography. The separation of ergometrine and ergometrinine was satisfactory, using Foster's method but the error was rather large for quantitative work. Good results were obtained, however, by extracting the alkaloid from the paper with a pH 8.0 buffer solution and the amount determined by the usual colorimetric procedure. The recovery was 95.4% with a standard deviation of ±3.5%. This method has been applied to the analysis of ergots grown on Elymus dahuricus Turcz. and Elymus sibiricus L. The ergometrine contents were 0.025 and 0.021% respectively. When a solution of pure ergometrine was added to the sample solution before developing the chromatogram, the separation of ergometrine from the other alkaloids was improved and the spots were better defined, thus enabling the analysis of ergot samples with low alkaloid content. Descending technique was used for the chromatography of water-insoluble alkaloids. Filter paper impregnated with a mixture of formamide, acetone and pH 2.0 buffer solution was the stationary phase and chloroform saturated with pH 2.0 buffer solution was used as the developing liquid. Good separation of the three groups of alkaloids-ergometrine, ergotamine and ergotoxine groups-was thus obtained. The results showed that ergots grown on the following host plants: 1. Elymus dahuricus Turcz. 2. Elymus dasystachys Trin. 3. Elymus sibiricus L. 4. Calamagrostis epigious Roth. all contained the 3 groups of ergot alkaloids.