Quantitative determination of total alkaloid in Corydalis Ochotensis Turcz by colorimetry

A quantitative determination of the total alkaloid in Corydalis Ochotensis Turcz was established by acid dye colorimetry. The effects of wavelength, pH of the phosphate buffer and the quantity of acid dye were studied. Two different dyes were compared according to the yield of berberine hydrochloride. The method with bromophenol blue dye was proved to be more accurate, more stable with good reproducibility in testing experiments. So, it was fit for quantitative determination of total alkaloid in Corydalis Ochotensis Turcz.