J. R. Robinson

We studied the effects of ammonia treatment on microbial populations during the fermentation of corn silage. We also compared the effects of ammonia to a preservative containing buffered propionic acid and other antifungal compounds on the fermentation and aerobic stability of corn silage. In the first experiment, whole-plant corn was ensiled without treatment or treated with ammonia-N to supply an additional 0.3% N (fresh-forage basis). The addition of ammonia immediately increased silage pH and had no effect on numbers of lactic acid bacteria, but delayed their growth compared with untreated silage. Numbers of enterobacteria declined more slowly, but numbers of yeasts and molds declined more quickly in silage treated with ammonia. During the early stages of ensiling, lactic acid increased more rapidly in untreated than in treated silage. The reverse was true for acetic acid concentrations. When exposed to air, growth of yeasts and molds was delayed in ammonia-treated silage. In a second experiment, various levels (0.1 to 0.3%, fresh weight) of ammonium-N or a preservative with buffered propionic acid were added to whole-plant corn and allowed to ensile for 106 d. Silage treated with ammonia had a greater ratio of L- to D-lactic acid than did other silages. Untreated silage was aerobically stable for 32.3 h, whereas the low (42 h) and moderate (52.7 h) concentrations of both additives numerically improved aerobic stability. High concentrations of ammonia-N (0.3%) or a buffered propionic acid preservative (0.3%), markedly improved the aerobic stability of corn silage (82 and 69 h for ammonia and propionic acid-treated silage, respectively).

Research Article| January 01 1949 Some effects of glucose and calcium upon the metabolism of kidney slices from adult and newborn rats J. R. Robinson J. R. Robinson 1Department of Experimental Medicine, University of Cambridge Search for other works by this author on: This Site PubMed Google Scholar Author and article information Publisher: Portland Press Ltd © 1949 CAMBRIDGE UNIVERSITY PRESS1949 Biochem J (1949) 45 (1): 68–74. https://doi.org/10.1042/bj0450068 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn Email Cite Icon Cite Get Permissions Citation J. R. Robinson; Some effects of glucose and calcium upon the metabolism of kidney slices from adult and newborn rats. Biochem J 1 January 1949; 45 (1): 68–74. doi: https://doi.org/10.1042/bj0450068 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Journal Search Advanced Search This content is only available as a PDF. © 1949 CAMBRIDGE UNIVERSITY PRESS1949 Article PDF first page preview Close Modal You do not currently have access to this content.

Abstract The total amount of water in slices of the renal cortex of adult rats was determined after they had been exposed to saline solutions with concentrations from 0·58 to 0·03 os·mol. /l. : (a) When metabolism was suppressed by lowering the temperature to 0 to 4°C. (b) When the slices were respiring in oxygen at 38·5°C. (c) When respiration was inhibited by cyanide at 38·5°C. (d) When metabolism was reduced by cooling to temperatures between 38 and 16°C. The amount of water in slices at 0 to 4°C varied inversely with the concentration of the medium, and when this concentration was less than 0·58 os·mol. /l. the slices contained more water than the tissue in vivo. Slices respiring at 38·5°C in solutions more dilute than 0·58 os·mol. /l. contained considerably less water than slices in the same solutions at 0 to 4°C, and dilution of the medium from 0·58 to 0·19 os·mol. /l. produced a much smaller increase in the amount of water in the slices when they were respiring than when they were at 0 to 4°C. The uptake of oxygen at 38·5°C was independent of the concentration of the medium between 0·45 and 0·12 os·mol. /l. Slices whose respiration was inhibited by cyanide in ‘isotonic’ (0·30 osm) solutions at 38·5°C contained more water than slices respiring freely in concentrations as low as 0·06 os·mol./l. The changes produced by cyanide in oxygen uptake and in water content were both reversible. When the uptake of oxygen was reduced by cooling to 30°C, the amount of water in the slices decreased. Evidence is presented that all the changes in water content were almost complete in 2 min., and were then maintained for several hours. These results suggest that respiration is more important than the osmotic pressure of the external medium in determining the amount of water in cells. They cannot be explained by the orthodox theory that mammalian cells are in osmotic equilibrium with their surroundings, and indeed they suggest that the osmotic pressure of the cell fluids is normally 50 to 100% greater than that of the extracellular fluids. All the observations can be explained if energy derived from respiration is used to expel water from the cells, so that a steady state is maintained in which the higher internal osmotic pressure causes water to diffuse in to the cells as fast as it is pumped out. The energy required to maintain the observed amount of water in the respiring slices was calculated by a simple theoretical treatment. It was found to be proportional to the observed oxygen uptake and to be a small percentage of its energy equivalent.

Abstract The oxygen consumption of liver slices from adult rats was not significantly affected by the concentration of the medium when this lay between 0⋅20 and 0⋅45 osM/1. Alterations outside this range in either direction reduced the uptake of oxygen. Slices respiring at 38⋅5°C in solutions varying from 0⋅10 to 0⋅58 osm/1. always contained less water than slices in similar solutions at temperatures between 1 and 3°C. This difference was most noticeable with concentrations which did not inhibit respiration. When the oxygen uptake of slices in 0⋅30 osM media a t 38⋅5°C was inhibited by cyanide, the water content of the slices increased. Oxygen consumption increased and water content decreased again when cyanide was removed from the media. Small concentrations of 2, 4-dinitrophenol increased and larger concentrations reduced the uptake of oxygen, but both increased the amount of water in the tissue. The results suggest that the intracellular fluids are hypertonic, and that respiration governs the water balance of the tissue because some of the energy which it releases is used for active transport of water out of the cells through the mediation of compounds containing high-energy phosphate bonds. It is suggested that cloudy swelling results from a disturbance of the active transport of water.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTerpenoids. XIV. The Constitution and Biogenesis of Marasmic Acid1,2J. J. Dugan, P. de Mayo, M. Nisbet, J. R. Robinson, and M. AnchelCite this: J. Am. Chem. Soc. 1966, 88, 12, 2838–2844Publication Date (Print):June 1, 1966Publication History Published online1 May 2002Published inissue 1 June 1966https://pubs.acs.org/doi/10.1021/ja00964a039https://doi.org/10.1021/ja00964a039research-articleACS PublicationsRequest reuse permissionsArticle Views139Altmetric-Citations44LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts