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The cell walls of Eragrostis tef: variations in chemical composition and digestibility

Published online by Cambridge University Press:  27 March 2009

E. Jane Morris
Affiliation:
National Chemical Research Laboratory, P.O. Box 395, Pretoria 0001, Republic of South Africa

Summary

Teff (Eragrostis tef) was cut at various stages of growth and divided into leaf, stem (including leaf sheath) and inflorescence. Cell walls were isolated from the leaf and stem fractions and their composition determined. Acetyl groups and individual sugars were determined by gas-liquid chromatography.

Recoveries of cell walls from the same fresh weight of leaves or stems were similar at each stage of growth, but increased with maturity.

Throughout the growing season the leaf cell walls differed in composition from those of the stem. At the start of growth the leaves had a lower content of xylose and acetyl groups but were otherwise similar to the stems. However, with increasing maturity and the production of a flowering stem the stem cell wall composition changed much more than that of the leaf cell walls, with a marked decrease in the content of arabinose and an increase in the content of lignin and acetyl. Over the same period the leaf cell walls showed a smaller increase in acetyl content and decrease in arabinose and uronic acid, but were otherwise unchanged.

Digestion of the cell walls with a fungal cellulase preparation showed that although the two cell wall types were equally degradable while the grass was in the vegetative state, the digestibility of the stem cell walls decreased well below that of the leaves with the onset of maturity and the production of a flowering stem. This was confirmed by in vivo incubations of the cell walls in nylon bags.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1980

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References

Bacon, J. S. D., Gordon, A. H., Morris, E. J. &. Farmer, V. C. (1975). Acetyl groups in cell-wall preparations from higher plants. Biochemical Journal 149, 485487.CrossRefGoogle ScholarPubMed
Bailey, R. W. (1973a). Structural carbohydrates. In Chemistry and Biochemistry of Herbage (ed. Butler, G. W. and Bailey, R. W.), vol. 1, pp. 157211. New York: Academic Press.Google Scholar
Bailey, R. W. (1973b). Water in herbage. In Chemistry and Biochemistry of Herbage (ed. Butler, G. W. and Bailey, R. W.), vol. 11, pp. 1324. New York: Academic Press.Google Scholar
Bailey, R. W. & Connor, H. E. (1972). Structural carbohydrates in leaf blades and sheaths in the arundinoid grass Chionochloa. New Zealand Journal of Botany 10, 533544.CrossRefGoogle Scholar
Bailey, R. W. & Hunt, W. F. (1973). Structural carbohydrate levels in kikuyu grass and ryegrass grown under identical conditions. New Zealand Journal of Agricultural Research 16, 203205.CrossRefGoogle Scholar
Bethge, P. O. & Lindstrom, K. (1973). Determination of O-acetyl groups in wood. Svensk Papperstidning 76, 645649.Google Scholar
Blumenkrantz, N. & Asboe-Hansen, G. (1973). New method for quantitative determination of uronic acids. Analytical Biochemistry 54, 484489.CrossRefGoogle ScholarPubMed
Chenost, M., Grenet, E., Demarquilly, C. & Jarrige, R. (1970). The use of the nylon bag technique for the study of forage digestion in the rumen and for predicting feed value. Proceedings of the ilth International Grassland Congress, pp. 697701.Google Scholar
Dekker, R. F. H. & Richards, G. N. (1973). Digestion of polysaooharide constituents of tropical pasture herbage in the bovine rumen. Part II: Spear grass (Heteropogon contortus). Carbohydrate Research 27, 1—4.CrossRefGoogle Scholar
Dubois, M., Gilles, K. A., Hamilton, J. K., Rebers, P. A. & Smith, F. (1956). Colorimetric method for determination of sugars and related substances. Analytical Chemistry 28, 350356.CrossRefGoogle Scholar
Ford, C. W. (1978). Effect of partial delignification on the in vitro digestibility of cell wall polysaccharides in Digitaria decumbens (pangola grass). Australian Journal of Agricultural Research 29, 1157—1166.CrossRefGoogle Scholar
Gausseres, B. (1965). Étude des variations des teneurs en glucides cytoplasmiques et membranaires du dactyle au cours de I'année. Annales de Biologie Animate, Biochimie, Biophysique 5, 361381.CrossRefGoogle Scholar
Gordon, A. H., Hay, A. J., Dinsdale, D. & Bacon, J. S. D. (1977). Polysaccharides and associated components of mesophyll cell-walls prepared from grasses. Carbohydrate Research 57, 235248.CrossRefGoogle Scholar
Gutiérrez-Vargas, R., Arroyo-Aquilú, J. A. & Ramirez-Ortiz, A. (1978). Voluntary intake, chemical composition, and nutrient digestibility of pangolagrass and stargrass hays. Journal of Agriculture of the University of Puerto Rico 62, 389398.Google Scholar
Jarrige, R. (1960). The membrane constituents of herbage. Proceedings of the 8th International Grassland Congress, pp. 628635.Google Scholar
Jarrige, R. (1963). Les constituants membranaires des plantes fourragères. Annales de Biologie Animate, Biochimie, Biophysiquei 3, 143190.CrossRefGoogle Scholar
Mackenzie, D. J. & Wylam, C. B. (1957). Analytical studies on the oarbohydrates of grasses and clovers. VIII. Changes in carbohydrate composition during the growth of perennial ryegrass. Journal of the Science of Food and Agriculture 8, 3845.CrossRefGoogle Scholar
Moir, K. W., Wilson, J. R. & Blight, G. W. (1977). The in vitro digested cell wall and fermentation characteristics of grasses as affected by temperature and humidity during their growth. Journal of Agricultural Science, Cambridge 88, 217222.CrossRefGoogle Scholar
Morris, E. J. & Bacon, J. S. D. (1977). The fate of acetyl groups and sugar components during the digestion of grass cell walls in sheep. Journal of Agricultural Science, Cambridge 89, 327340.CrossRefGoogle Scholar
Morrison, I. M. (1972). Semi-micro method for determination of lignin and its use in predicting digestibility of forage crops. Journal of the Science of Food and Agriculture 23, 453463.CrossRefGoogle ScholarPubMed
Mowat, D. N., Kwain, M. L. & Winch, J. E. (1969). Lignification and in vitro cell wall digestibility of plant parts. Canadian Journal of Plant Science 49, 499504.CrossRefGoogle Scholar
Sloneker, J. H. (1971). Determination of cellulose and apparent hemicellulose in plant tissue by gas-liquid chromatography. Analytical Biochemistry 43, 539546.CrossRefGoogle ScholarPubMed
Sloneker, J. H. (1972). In Methods in Carbohydrate Chemistry (ed. Whistler, R. J. and BeMiller, J. N.), vol. VI, pp. 2024. New York: Academic Press.Google Scholar
Van Soest, P. J. (1973). The uniformity and nutritive availability of cellulose. Federation Proceedings 32, 18041808.Google ScholarPubMed
Van Soest, P. J. & Wine, R. H. (1967). Use of detergents in the analysis of fibrous feeds. IV. Determination of plant cell-wall constituents. Journal of the Association of Official Analytical Chemists 50, 5055.Google Scholar
Waite, R. & Gorrod, A. R. N. (1959). The structural carbohydrates of grasses. Journal of the Science of Food and Agriculture 10, 308317.CrossRefGoogle Scholar
Webster, J. E., Shyrock, G. & Cox, P. (1963). The carbohydrate composition of two species of grama grasses. Oklahoma Agricultural Experimental Station Technical Bulletin T-104, 14 pp.Google Scholar
Wilkinson, W. S., Barbee, C. & Knox, F. E. (1968). Nutrient content of dehydrated coastal bermuda grass and pearl millet. Journal of Agricultural and Food Chemistry 16, 665668.CrossRefGoogle Scholar
Wilson, J. R. & Ford, C. W. (1971). Temperature influences on the growth, digestibility and carbohydrate composition of two tropical grasses, Panicum maximum var. trichoglume and Setaria spachelala, and two cultivars of the temperate grass Lolium perenne. Australian Journal of Agricultural Research 22, 563571.CrossRefGoogle Scholar