Purification and characterization of cannabichromenic acid synthase from Cannabis sativa

Cannabichromenic acid synthase was purified to:apparent homogeneity by sequ ential column chromatography including DEAE-cellulose, phenyl-Sepharose CL- 4B, and hydroxylapatite. The enzyme catalysed the oxidocyclization of canna bigerolic acid and cannabinerolic acid to cannabichromenic acid. The K-m va lues for both substrates were in the same order of magnitude although the V -max value for the former was higher than that for the latter. These result s suggested that cannabichromenic acid is predominantly formed from cannabi gerolic acid rather than cannabinerolic acid. The enzyme required neither m olecular oxygen nor hydrogen peroxide, indicating that the cannabichromenic acid synthase reaction proceeds through direct dehydrogenation without hyd roxylation. (C) 1998 Elsevier Science Ltd. All rights reserved.