Determination of a novel bitter amino acid, pulcherrimine, in the gonad ofthe green sea urchin Hemicentrotus pulcherrimus

A novel bitter amino acid, pulcherrimine was analyzed by reverse-phase high -performance liquid chromatography using a linear gradient elution consisti ng of methanol/aqueous/acetic acid and methanol/acetic acid mixture, after being labeled with dimethylaminoazobenzenesulfonyl chloride (Dabs-Cl). Line arity of the calibration curve for pulcherrimine was high (r=0.994) in the tested range from 0 to 4 mug/mL. By this method, the pulcherrimine content in the ovary and testis of the green sea urchin Hemicentrotus pulcherrimus, collected in the sea off Iwaki in November 1998, was analyzed. The mean pu lcherrimine content in the ovary was 1.37 mg/100 g. In contrast, no pulcher rimine was detected in all testes examined. Correlation between the bittern ess and the pulcherrimine content was statistically significant. These resu lts strongly support that pulcherrimine is a bitter principle in the green sea urchin ovaries.