A new method of determining berberine together with palmatine as well as the other accessory alkaloids in Coptis japonica MAKINO by spectrophotometric measurements has been deviced, after the seperation by TLC.
0.05 gram of powdered Coptis japonica MAKINO was extracted with methanol, which was chromatographed on the Kieselgel plate with a developer of a solvent mixture of butanolacetic acid-water=7:1:2. From the chromatogram (Fig. 1), berberine portion was scratched out and extracted with methanol. The absorption was measured through the filter of 420-440mμ and the berberine content was determined according to the calibration curve (Fig. 2) previously prepared. This manipulation takes about 9-10 hours and the recovery rate was found to be more than 95% in average (Table II, III). Considering from the seperation of berberine from the other accessory alkaloids completely, it is considered to be superior to the other method. This data was also compared with that by ionexchange resin method.