Abstract
L-[14C]Phenylalanine, fed to cell suspension cultures of Douglas fir, (Pseudotsuga menziesii Franco) was incorporated simultaneously, but at different rates, into (+)-catechin, (−)-epicatechin, and procyanidins of increasing molecular weight. Asymmetric labeling of dimers and polymers was demonstrated, with more label appearing in the upper than in the lower or terminal unit. In addition, the total pool of free monomers was 10 to 30 times more highly labeled than was this lower, terminal unit of dimers and higher oligomers. Since the dimer, epicatechin-catechin, contained more label than catechin-catechin, it is concluded that the carbocation with the 2,3-cis stereochemistry of (−)-epicatechin was formed more rapidly than was that of the 2,3-trans type of (+)-catechin.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Creasy L. L., Swain T. Structure of condensed tannins. Nature. 1965 Oct 9;208(5006):151–153. doi: 10.1038/208151a0. [DOI] [PubMed] [Google Scholar]
- Stafford H. A., Lester H. H. Proanthocyanidins and potential precursors in needles of douglas fir and in cell suspension cultures derived from seedling shoot tissues. Plant Physiol. 1981 Nov;68(5):1035–1040. doi: 10.1104/pp.68.5.1035. [DOI] [PMC free article] [PubMed] [Google Scholar]