Nitrogen Excretion in Ascidiacea

1957 ◽  
Vol 34 (3) ◽  
pp. 297-305
Author(s):  
IVAN GOODBODY
Keyword(s):  
Metabolic Rate ◽  
Blood Cells ◽  
Ciona Intestinalis ◽  
Nitrogen Excretion ◽  
Soluble Nitrogen ◽  
Filter Feeding ◽  
Protein Nitrogen ◽  
Insoluble Form ◽  
Ascidiella Aspersa

1. Ascidians, have hitherto been regarded eliminating their nitrogen in an insoluble form and storing the products either in special vesicles or in blood cells termed nephrocytes. 2. Three specks of ascidian have been studied: Ciona intestinalis, Ascidiella aspersa and Molgula manhatteniss. Evidence is brought forward to show that these ascidiane excrete soluble nitrogen chiefly in the form of ammonia. 3. The quantities of soluble non-protein nitrogen excreted are slightly higher than is found in the filter-feeding molluscs; this is probably due in part to an increased metabolic rate subsequent to transport and handling. 4. Ammonia may form as much as 95% of the total aon-protein nitrogen excreted. 5. The methods employed are subject to an error up to 10%.

EFFECTS OF GRADED DIETARY PROTEIN LEVELS ON UREA RECYCLING IN THE PIG

1982 ◽  
Vol 62 (4) ◽  
pp. 1193-1197 ◽  
Author(s):  
P. A. THACKER ◽  
J. P. BOWLAND ◽  
L. P. MILLIGAN ◽  
E. WELTZIEN
Keyword(s):  
Dietary Protein ◽  
Protein Diet ◽  
Nitrogen Excretion ◽  
Entry Rate ◽  
Protein Nitrogen ◽  
Protein Levels ◽  
Low Protein ◽  
Key Words Pig ◽  
Urea Recycling ◽  
Protein Diets

The kinetics of urea recycling were determined in six female crossbred pigs utilizing a radioisotope dilution technique. The experimental animals were fed three times daily 500 g of a corn-soybean meal diet formulated to contain 8.4, 15.8 or 24.7% crude protein. Nitrogen digestibility, urinary nitrogen excretion, total nitrogen excretion and retained nitrogen were highest on the 24.7% protein diet and decreased with decreasing dietary protein. Urea pool size, entry rate and excretion rate were also highest on the 24.7% protein diet and decreased with decreasing protein intake. Expressed as a percentage of the total entry rate, a significantly higher percentage of urea was recycled in pigs fed the low protein diets compared with those fed a higher protein diet. Key words: Pig, urea, recycling, kinetics, protein

Nitrogen Excretion in Ascidiacea II. Storage Excretion and the Uricolytic Enzyme System

1965 ◽  
Vol 42 (2) ◽  
pp. 299-305
Author(s):  
IVAN GOODBODY
Keyword(s):  
Uric Acid ◽  
Calcium Carbonate ◽  
Protein Metabolism ◽  
Enzyme System ◽  
Purine Metabolism ◽  
Nitrogen Excretion ◽  
Purine Base ◽  
Purine Bases ◽  
Ascidiella Aspersa

1. The evidence for the occurrence of storage excretion in ascidians is reviewed. Most species probably store uric acid or purine bases in some form. 2. The renal concretions of Ascidia nigra and Phallusia mammillata contain 50-60% uric acid, the remainder of the concretion is unidentified but is non-nitrogenous and is not calcium carbonate. In Ascidiella aspersa the concretion is predominantly composed of calcium carbonate and there is no significant quantity of uric acid or purine base. 3. Uric acid is also identified in Molgula manhattensis, Polycarpa obtecta, Pyura vittata and Herdmania momus. 4. Storage excretion probably results from a deficiency in the uricolytic enzyme system. It is concluded that while protein metabolism is ammonotelic, purine metabolism is uricotelic or xanthotelic.

The digestion of food by the grazing sheep. IV. The effect of mastication on the release of soluble plant nitrogen

1965 ◽  
Vol 16 (5) ◽  
pp. 855 ◽  
Author(s):  
JP Hogan
Keyword(s):  
Cold Water ◽  
Plant Cells ◽  
Soluble Nitrogen ◽  
Sheep Grazing ◽  
Protein Nitrogen ◽  
Plant Nitrogen ◽  
Grazing Sheep ◽  
Pasture Plants

The rate of release of soluble nitrogenous constituents from plant cells during the ingestion of green pasture plants has been studied. Boluses were collected either from sheep with oesophageal fistulae or from the rumen in sheep fitted with large rumen cannulae. Sheep grazing on pastures of different heights ingested food at widely varying rates. This was indicated by the rate of formation of boluses, which during 10-min collection periods ranged from 10.5 to 62.5 g/min. The rates at which bolus nitrogen reached the rumen ranged from 45 to 300 mg/min; of this, 20–45% (mean 26) was extractable with cold water. Approximately 50% of the extractable soluble nitrogen was protein nitrogen.

Effects of nitrogen fertilizers on total nitrogen, soluble nitrogen and soluble carbohydrate contents of grass

1962 ◽  
Vol 59 (3) ◽  
pp. 387-392 ◽  
Author(s):  
T. Z. Nowakowski
Keyword(s):  
Ammonium Sulphate ◽  
Total Nitrogen ◽  
Sodium Nitrate ◽  
Nitrogen Fertilizers ◽  
Soluble Carbohydrates ◽  
Soluble Carbohydrate ◽  
Soluble Nitrogen ◽  
Protein Nitrogen ◽  
Total N ◽  
Nitrate N

Italian rye-grass given ammonium sulphate or sodium nitrate at 56 or 112 lb. N/acre was analysed for total nitrogen, soluble nitrogen (non-protein-nitrogen) and soluble carbohydrates.Ten days after applying fertilizer the differences in total-N between the grass receiving 56 and grass receiving 112 lb. N/acre were very small. Total-N in grass decreased with growth, but the effect of the rate of nitrogen on total-N increased. At first the grass given sodium nitrate contained more soluble nitrogen than grass given ammonium sulphate, the difference being greater at 56 lb. N/acre; soluble nitrogen decreased with increasing growth. Ten days after applying fertilizer, the nitrate-N content of grass was very high (ranging from 0·1 to 0·9% in the D.M.) and it gradually decreased. At both levels of nitrogen application, grass given sodium nitrate contained much more nitrate-N than grass given ammonium sulphate. Forty days after applying nitrogen the nitrate-N contents of grass which received 56 and 112 1b. N/acre as ammonium sulphate were 0·039 and 0·222% of the dry matter, respectively; the grass supplied with sodium nitrate gave values of 0·082 and 0·438%.Total soluble carbohydrates in the grass were small early in growth and gradually increased. Nitrogen dressings had little effect on the content of soluble sugars (glucose + fructose + sucrose) but greatly decreased the fructosan. The pattern of changes in the total soluble carbohydrate content followed that in fructosan content. Early in growth, the total soluble carbohydrate/crude protein ratio was very small in grass from all treatments except the ‘control’. This ratio increased with growth and at the last sampling was 2·13 in grass receiving no nitrogen, and in grass supplied with 56 and 112 lb. N/acre as ammonium sulphate it was 1·44 and 0·72 respectively; the corresponding figures for grass receiving sodium nitrate were 1·13 and 0·66. The total soluble carbohydrate carbon/soluble nitrogen ratio in grass with no nitrogen was 18 at the first sampling and it increased gradually, reaching 70 at the last sampling. This ratio was considerably less with all nitrogen treatments than with ‘control’. The values obtained with 112 lb. N/acre were less than those obtained with 561b./acre, irrespective of the form of nitrogen used.The relationship between the soluble carbohydrate carbon content and the soluble nitrogen in grass is illustrated graphically and discussed.

Note. Effect of brining time on proteolytic changes in Idiazábal cheese during ripening / Nota. Cambios proteolíticos durante la maduración del queso Idiazábal por efecto del tiempo en salmuera

1996 ◽  
Vol 2 (5) ◽  
pp. 335-339 ◽  
Author(s):  
F.C. Ibáñez ◽  
A.I. Ordóñez ◽  
M.S. Vicente ◽  
M.I. Torres ◽  
Y. Barcina
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
Total Nitrogen ◽  
Free Amino Acids ◽  
Free Amino ◽  
Dry Matter ◽  
Electrophoretic Analysis ◽  
Soluble Nitrogen ◽  
Clear Trend ◽  
Protein Nitrogen

Idiazábal cheeses were made employing brining times of 12 h (batch A) and 36 h (batch B). Proteolytic changes in both batches were examined over 270 d of ripening; proteolysis was low in both batches, but lower in batch B than in batch A. Electrophoretic analysis revealed incom plete breakdown of αs and β-caseins at the end of the ripening period, particularly in batch B. The proportion of soluble nitrogen as a percentage of total nitrogen was 17.55% in batch B and 19.48% in batch A, while the proportion of non-protein nitrogen was 11.78% in batch B and 15.16% in batch A. The proportion of non-protein nitrogen as a percentage of soluble nitrogen was 67.17% in batch B and 77.88% in batch A. The free amino acids, the smallest non-protein nitrogen frac tion, attained values of 1203 mg/100 g of dry matter in batch B and 1902 mg/100 g of dry matter in batch A. After 60 d of ripening, the main free amino acids were glutamic acid, valine, leucine, lysine, and phenylalanine in both batches, although levels were higher in the batch with the shorter brining time. There was no clear trend in the non-protein-forming amino acids with either ripening time or brining time.

106. The Role of Rennet in the Ripening of Cheddar Cheese

1935 ◽  
Vol 6 (2) ◽  
pp. 204-217 ◽  
Author(s):  
I. R. Sherwood
Keyword(s):  
Normal Control ◽  
Strong Evidence ◽  
Volatile Acid ◽  
Soluble Nitrogen ◽  
Protein Nitrogen ◽  
Ripening Process ◽  
Bacterial Action ◽  
Proteolytic Action ◽  
Activity Of Enzymes

Attempts were made to eliminate the bacterial factor in Cheddar cheeseripening, through the agency of chloroform, and an assessment of the role of rennet was thus rendered possible.After investigating the effect of chloroform and toluene upon the proteolytic action of rennet and trypsin in milk, the results obtained were applied in studies upon the ripening of cheese in the presence of chloroform. Cheese of normal manufacture was chloroformed at the salting stage or one week or more after manufacture (when the curd had lost its rubbery nature and the germicide was more easily incorporated). Owing to the weakened activity of enzymes in the presence of germicides, it was necessary to employ larger proportions than usual of rennet, measured additions generally being made at the time when the chloroform was added. Under these conditions the general course of protein degradation, as measured by determinations of soluble nitrogen and non-protein nitrogen, was found to be identical with that occurring in normal control cheeses. Strong evidence was thus afforded that rennet is the only important agent attacking cheese protein during the ripening process.In the partition between the non-protein constituents of the normal and chloroformed cheeses, respectively, there were observed definite differences which tended to remain constant over the greater part of the ripening period. The relatively higher proportion of subpeptone nitrogen in the normal cheese was shown to be due, at least in some measure, to bacterial action.Cheese ripened in the presence of chloroform developed no volatile acid, and no cheese flavour could be detected.

scholarly journals Physiology of Pea Fruits I. the Developing Fruit

1955 ◽  
Vol 8 (2) ◽  
pp. 137 ◽  
Author(s):  
HS Mckee ◽  
RN Robertson ◽  
JB Lee
Keyword(s):  
Ascorbic Acid ◽  
Cell Volume ◽  
Starch Content ◽  
Dry Weight ◽  
Metabolic Changes ◽  
Soluble Carbohydrate ◽  
Soluble Nitrogen ◽  
Fresh Weight ◽  
Protein Nitrogen ◽  
Respiration Rates

Pea fruits from two crops were sampled at different times from flowering. Changes in the fresh weight, dry weight, starch, soluble carbohydrate, protein nitrogen, and soluble nitrogen in both seeds and hulls were followed in two seasons and related Jo the changes in cell volume in the seeds. In one season respiration rates and phosphate, pectin, and ascorbic acid contents were also investigated. The seeds gained more carbohydrate and nitrogen than was lost by the hulls. Starch and protein were synthesized rapidly by the seeds. The increase in starch content in the seeds was followed by a decrease in soluble carbohydrate content, after which the seed ceased to accumulate water. These metabolic changes are discussed in the light of recent biochemical knowledge, and in relation to more detailed biochemical investigations in progress.

Toxin jararhagin in low doses induces interstitial edema and increases the metabolic rate and red blood cells in mice

Toxicon ◽  
2006 ◽  
Vol 48 (8) ◽  
pp. 1060-1067 ◽  
Author(s):  
Guilherme Francisco ◽  
Fernando J. Zara ◽  
Durvanei A. Maria ◽  
Ariovaldo P. Cruz-Neto
Keyword(s):  
Metabolic Rate ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Low Doses ◽  
Interstitial Edema
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