The Norcoclaurine Pathway is Operative in Berberine Biosynthesis in Coptis japonica

Abstract

The commercially used cell suspension culture of Coptis japonica Makino (Ranunculaceae) incorporates [β-¹³ C]tyrosine into both halves of the berberine molecule (isoquinoline and benzyl portion) while L-[3′-¹⁸ O]DOPA only labels the isoquinoline portion of this molecule. This labelling pattern indicates that different C₆-C₂ units derived from tyrosine form this molecule. This result and the incorporation of (S)-[1-¹³ C] norcoclaurine into berberine demonstrates that the biosynthesis of protoberberine alkaloids in Coptis involves the norcoclaurine but not the norlaudanosoline pathway.

Coptis japonica - Ranunculaceae - biosynthesis - norcoclaurine pathway