An Enzyme Extract from Douglas-Fir Sapwood and Its Relationship To Brown Staining
Keywords:
Polyphenol oxidase, Douglas-fir sapwood, chemical stains, brown stains, protein extraction, enzyme activityAbstract
A chemical or enzymatic brown stain in sapwood of Douglas-fir has caused financial losses to lumber producers, particularly those producing valuable clear grades of export lumber. This work shows that the brown stain may be caused, at least in part, by an enzyme system in the sapwood. Buffered extracts of Douglas-fir sapwood showed enzyme activity when added to solutions containing o-diphenol and polyphenol compounds. No activity for monophenol substrates was detected. The enzymatic extract showed two pH optima for activity, one at pH 5.5 and one at pH 8.0, with the activity at pH 8.0 being somewhat greater. The activity was also temperature-dependent, with the highest activity at 35°. The extract showed highest activities with the compounds (—)-epicatechin, dihydroquercetin, and 4-methylcatechol.References
Arvey, S. W. 1993. Chemical brown stain of Douglasfir wood. Ph.D. thesis, Oregon State University, Corvallis, OR.nBio-Rad. 1989. Bio-Rad protein assay. Bio-Rad technical literature. Richmond, CA.nFlurkey, W. H., and J. J. Jen. 1978. Peroxidase and polyphenol oxidase activities in developing peaches. J. Food Sci. 43:1826-1828.nGomori, G. 1955. Preparation of buffers for use in enzyme studies. Pages 138-146 in S. P. Colowick and N. O. Kaplan, eds. Methods in enzymology, vol. 1. Academic Press, New York, NY.nGuttridge, S., and D. A. Robb. 1975. Catecholase activity of Neurospora tyrosinase. Eur. J. Biochem. 54: 107-116.nInteresse, F. S., P. Ruggiero, G. D'avella, and F. Lamparelli. 1980. Partial purification of some properties of wheat (Triticum aestivum) o-diphenolase. J. Sci. Food Agric. 31:459-466.nJolley, R. L., L. H. Evans, N. Makino, and H. S. Mason. 1974. Oxytyrosinase. J. Biol. Chem. 249(2):335-345.nMayer, A.M., and E. Harel. 1979. Review: Polyphenol oxidases in plants. Phytochem. 18:193-215.nMiller, D. J., D. M. Knutson, and R. D. Tocher. 1983. Chemical brown staining of Douglas-fir sapwood. Forest Prod. J. 33(4):44-48.nOta, M., S. Onodera, M. Ohira, and K. Taneda. 1991. The chemistry of color changes in Kiri wood (Paulownia tomentosa Steud.) II. Radial distributions and seasonal variations of the contents of total phenolics, of caffeic acid sugar esters, and of kiri peroxidase activity in the xylem, plus some properties of kiri peroxidase. Mokuzai Gakkaishi 37(3):254-260.nSong, H.-K. 1988. Chemistry of phenolic stains in Douglas-fir sapwood. Ph.D. thesis, Oregon State University, Corvallis, OR.nSpector, T. 1979. Refinement of the Coomassie Blue method of protein quantification. Anal. Biochem. 86: 142-146.nWissemann, K. W., and C. Y. Lee. 1981. Characterization of polyphenoloxidase from Ravat 51 and Niagara grapes. J. Food Sci. 46:506-508, 514.n
Downloads
Published
Issue
Section
License
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.
