Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-05T02:37:38.915Z Has data issue: false hasContentIssue false

Ruminal digestion of chloroplasts and the protection of protein by glutaraldehyde treatment

Published online by Cambridge University Press:  27 March 2009

J. L. Mangan
Affiliation:
Biochemistry Department, A.R.C. Institute of Animal Physiology, Babraham, Cambridge CB2 4AT
Janet West
Affiliation:
Biochemistry Department, A.R.C. Institute of Animal Physiology, Babraham, Cambridge CB2 4AT

Summary

Chloroplasts, 50–80% intact, were prepared from kale (Brassica oleracea L. var. Marrowstem) by rapid homogenization (3·5 sec) of deveined leaves into partially frozen buffer pH 7·4 made 0·4 M with sucrose, and separated by differential centrifugation. Chloroplasts from 10 kg leaves were administered to the rumen of a sheep and the degradation followed by analysis of the rumen fluid which was collected continuously. Particulate matter of the rumen fluid was separated on discontinuous sucrose density gradients, 8 ml each of 35, 46, 50, 65 and 75% (w/v), centrifuging at 300 g for 1 h at + 2 °C. Chloroplasts were rapidly ingested by entodiniomorphid protozoa and digested with no detectable increase in soluble nitrogen in the rumen fluid. No net production of ammonia occurred but δ-amino-valeric acid increased indicating that amino acid transformations had occurred. Chlorophyll in the ingested chloroplasts was rapidly degraded with a half-life of 50–60 min. In contrast a similar amount of soluble casein added to the rumen degraded with a half-life of 13–14 min with large increase in soluble nitrogen consisting of peptides, amino acids, ammonia and δ-amino-valeric acid. Glutaraldehyde treated chloroplasts were also ingested by protozoa, chlorophyll was rapidly degraded but there was no increase in the soluble nitrogen of the rumen fluid, including ammonia and δ-amino-valeric acid. Water disrupted chloroplasts released soluble protein and in the rumen behaved like casein, producing high proportions of ammonia and δ-amino-valeric acid. The significance of these experiments in the protection of soluble leaf protein from degradation in the rumen of pasture-fed animals is discussed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1977

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Arnon, D. I. (1949). Copper enzymes in isolated chloroplasts. Polyphenoloxidase in Beta vulgaris. Plant Physiology 24, 115.CrossRefGoogle ScholarPubMed
Blaxter, K. L. & Martin, A. K. (1962). The utilization of protein as a source of energy in fattening sheep. British Journal of Nutrition 16, 397407.CrossRefGoogle ScholarPubMed
Bryant, A. M. (1964). The release of plant cell contents and its relation to bloat. Proceedings of the New Zealand Society of Animal Production 24, 5766.Google Scholar
Chalmers, M. I., Cuthbertson, D. P. & Synge, R. L. M. (1954). Ruminal ammonia formation in relation to protein requirement of sheep. I. Duodenal administration and heat processing as factors influencing fate of casein supplements. Journal of Agricultural Science, Cambridge 44, 254–62.CrossRefGoogle Scholar
Coleman, G. S. (1964). The metabolism of Escherichia coli and other bacteria by Entodinium caudatum. Journal of General Microbiology 37, 209–23.CrossRefGoogle Scholar
Coleman, G. S. (1967). The metabolism of the amino acids of Escherichia coli and other bacteria by the rumen ciliate Entodinium caudatum. Journal of General Microbiology 47, 449–64.CrossRefGoogle Scholar
Croft, D. N. & Lubran, M. (1965). The estimation of deoxyribonucleio acid in the presence of sialic acid: application to analysis of human gastric washings. Biochemical Journal 95, 612–20.CrossRefGoogle ScholarPubMed
Dawson, R. M. C. & Hemlington, N. (1974). Digestion of grass lipids and pigments in the sheep rumen. British Journal of Nutrition 32, 327–40.CrossRefGoogle ScholarPubMed
El Shazley, K. (1952). Degradation of protein in the rumen of sheep. 2. The action of rumen microorganisms on amino acids. Biochemical Journal 51, 647–53.CrossRefGoogle Scholar
Hall, F. J., West, J. & Coleman, G. S. (1974). Fine structural studies on the digestion of chloroplasts in the rumen ciliate Entodinium caudatum. Tissue and Cell 6, 243–53.CrossRefGoogle ScholarPubMed
Harrison, F. A. (1974). The Babraham metabolism cage for sheep. Journal of Physiology 242, 20P.Google ScholarPubMed
Hyden, S. (1956). A turbidimetric method for the determination of higher polyethylene glycols in biological materials. Kungliga Lantbruckshögsholans Annalen 22, 139–45.Google Scholar
Jarrett, I. G. (1948). The production of rumen and abomasal fistulae in sheep. Journal of the Council for Scientific and Industrial Research, Australia 21, 311–15.Google Scholar
Kirk, J. T. O. & Tilney-Bassett, R. A. E. (1967). The Plastids: Their Chemistry, Structure, Growth and Inheritance. London: W. H. Freeman & Co.Google Scholar
Leech, R. M. (1966). Biochemistry of Chloroplasts, vol. 1 (ed. Goodwin, P. T. W.). London: Academic Press.Google Scholar
McDougall, E. I. (1948). Studies on ruminant saliva. I. The composition and output of sheep's saliva. Biochemical Journal 43, 99109.CrossRefGoogle ScholarPubMed
Mangan, J. L. (1972). Quantitative studies on nitrogen metabolism in the bovine rumen. The rate of proteolysis of casein and ovalbumin and the release and metabolism of free amino acids. British Journal of Nutrition 27, 261–83.CrossRefGoogle ScholarPubMed
Mangan, J. L. & Pryor, M. J. (1968). Quantitative studies on the degradation of chloroplasts in the rumen. Journal of Physiology 200, 1819P.Google Scholar
Mangan, J. L. & Weight, P. C. (1968). The measurement of rumen volumes of sheep and cattle with lithium salts. Research in Veterinary Science 9, 366–75.CrossRefGoogle ScholarPubMed
Reid, C. S. W., Lyttleton, J. W. & Mangan, J. L. (1962). Bloat in cattle. XXIV. A method of measuring the effectiveness of chewing in the release of plant cell contents from ingested feed. New Zealand Journal of Agricultural Research 5, 237–48.CrossRefGoogle Scholar
Stifel, F. B., Vetter, R. L., Allen, R. S. & Horner, H. T. (1968). Chemical and ultrastructural relationships between alfalfa leaf chloroplasts and bloat. Phytochemistry 7, 355–64.CrossRefGoogle Scholar
West, J. & Mangan, J. L. (1970). Effects of glutaraldehyde on the protein loss and photochemical properties of kale chloroplasts: preliminary studies on food conversion. Nature 228, 466–8.CrossRefGoogle ScholarPubMed
West, J. & Mangan, J. L. (1972). The digestion of chloroplasts in the rumen of sheep and the effect of disruption and glutai aldehyde treatment. Proceedings of the Nutrition Society 31, 108A.Google Scholar
West, J. & Mangan, J. L. (1973). A comparison of glutaraldehyde and formaldehyde fixation of isolated pea chloroplasts and its implications for the treatment of herbage for nutritional studies. Journal of Agricultural Science, Cambridge 80, 399406.CrossRefGoogle Scholar
Wright, P. C. (1967). Fifth Colloquium on Amino Acid Analysis, p. 164. Monograph 2, Technicon International Division, Domont, France.Google Scholar