Biosynthesis of Two Dilignol Rhamnosides in Leaves of <i>Thuja Plicata</i> Donn

Authors

  • Gary D. Manners
  • Eric P. Swan

Keywords:

<i>Thuja plicata</i>, biosynthesis, anabolism, dilignols, phenyl propane, dimers, lignification, glycosides, leaves, needles

Abstract

One of a series of dilignol glycosides previously isolated from western red cedar leaves has now been identified as 2, 3-dihydro-7-hydroxy-2- (4'-hydroxy-3'methoxyphenyl)-3-hydroxymethyl-5-benzofuran-propan-3"-0-α-L-rhamnopyranoside. In an experiment to determine biosynthesis rate, cut western red cedar leaves took up 37% radioactive phenylalanine (label) after 10 h. The newly identified compound took 3 h to reach a maximum uptake of label of 0.4%. A previously identified dilignol glycoside reached a maximum uptake of 0.3% in the same period. Both glycosides in leaves were rapidly anabolized, therefore, and since their label decreased after 5 h, they were precursors to other unknown compounds. The possible role of these glycosides in wound response or leaf lignin formation is considered.

References

Freudenberg, K. 1962. Forschunger auf Lignin. Fortschr. Chem. Org. Naturstoffe20:41-72.nKratzl, K. 1965. Lignin-its biochemistry and structure. Pages 157-179 in W. A. Cote ed. Cellular ultrastructure of woody plants. Syracuse University Press, Syracuse, N.Y.nManners, G. D., and E. P. Swan. 1971. Isolation and structure of a dilignol rhamnoside from the leaves of Thuja plicata trees. Can. J. Chem.49:3607-3611.nManners, G. D. 1970. Isolation and characterization of actively anabolized dilignol rhamnosides in the leaves of western red cedar (Thuja plicata Donn). Ph.D. thesis, University of British Columbia, Vancouver, B.C.nManners, G. D. 1974. Oxidation-liquid scintillation radio-assay of phenolics from cellulose thin-layer chromatography plates. J. Chrom.90:275-283.nNeish, A. C. 1965. Coumarins, phenyl propanes and lignin. Pages 601-611 in J. Bonner and J. E. Varner, eds. Plant biochemistry. Academic Press, New York.nPopoff, T., and O. Theander. 1976. Phenolic glycosides from Pinus sylvestrisL. Appl. Polym. Symp.28:1341-1347.n

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Published

2007-06-05

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Section

Research Contributions