EXTRACTION AND HPLC DETERMINATION OF RANUNCULIN IN SPECIES OF THE BUTTERCUP FAMILY

New extraction procedures are described for the isolation and purifica tion of ranunculin, the glycoside in members of the buttercup family w hich, upon autolysis, yield the vesicant oil, protoanemonin. The proce dures permit the efficient determination of ranunculin in plant extrac ts by normal phase HPLC. Ranunculin levels in plant tissue ranged from 1.5 to 19.9% on a dry matter basis. Of the 11 species examined, 5 wer e new detections of ranunculin in the Ranunculaceae. The glycoside was rapidly hydrolyzed at room temperature in the presence of beta-glucos idase as shown by HPLC of the reaction mixture. Autolysis occurred in aqueous acetone extracts at room temperature but not at -5 degrees C. Autolysis also occurred during cryogenic storage of plant tissue. Havi ng extracted ranunculin with conventional solvents in the absence of a cid, the glycoside can now be accepted as the natural storage form of protoanemonin and not an artifact arising from acid extraction.