DISTRIBUTION OF NITROGEN IN REPRESENTATIVE CANADIAN SOILS

1977 ◽  
Vol 57 (4) ◽  
pp. 445-456 ◽  
Author(s):  
F. J. SOWDEN
Keyword(s):  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Total Nitrogen ◽  
Amino Sugar ◽  
Peat Soils ◽  
Protein Nitrogen ◽  
Amino Acid Nitrogen ◽  
Canadian Soils ◽  
Mineral Soils

Forms of nitrogen in 92 samples were measured in a study designed to determine the similarities and differences in the nitrogen distribution in various horizons of a wide range of Canadian soils. The samples, representing all of the nine soil orders, were chosen from different climate and vegetation zones. Some peat soils were analyzed also. The data were first grouped according to the nitrogen content of the samples, but the amino acid composition of the soil "protein" did not appear to be related to this. The data were then grouped according to LFH, A, B and C horizons and also according to the Ah, Ap, Ae, Bhf, Bh, Bm and Bt layers. Again, few significant differences in the amino acid composition could be found. Data for the average amino acid composition and standard deviations for 92 mineral soils, 6 LFH and 2 ’O’ horizons of these and 18 peat soils were calculated. Since the analytical and sampling errors appear to be relatively small and would not account for all the variation between samples, there appeared to be real but relatively small and random differences in the amino acid composition of the different samples. The data for the individual soils supported this conclusion; for instance, some samples had very small or barely detectable amounts of hydroxyproline, while with other soils it made up 1–2% of the amino acid nitrogen. The amino sugar composition was more variable and the glucosamine/galactosamine ratio varied from 2:1 for the LFH horizons to 1:1 for the peat soils. In general, however, the soil "protein", which is probably largely the result of microbial degradation and synthesis, is remarkably similar to its amino acid composition. Amino acid nitrogen made up over half of the total nitrogen of the LFH and O horizons. This underestimated the "protein" nitrogen, since there is probably some amide nitrogen (about 5%) not included. In the mineral soils probably about 40% was "protein" nitrogen (including aminde), 5% was amino sugar nitrogen, 18% hydrolyzable unidentified nitrogen and 13.5% was insoluble in the acid used for hydrolysis. Clay-fixed ammonium made up 17% of the total nitrogen and much of the hydrolyzable ammonium came from this.

scholarly journals On the Nutrition and Metabolism of Zooplankton II. The relationship between the marine copepod Calanus helgolandicus and particulate material in Plymouth sea water, in terms of amino acid composition

1963 ◽  
Vol 43 (2) ◽  
pp. 495-511 ◽  
Author(s):  
C. B. Cowey ◽  
E. D. S. Corner
Keyword(s):  
Amino Acids ◽  
Body Weight ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Total Nitrogen ◽  
Skeletonema Costatum ◽  
Particulate Material ◽  
Amino Acid Nitrogen ◽  
Calanus Helgolandicus

The amino acid composition of adult female Calanus helgolandicus Claus and particulate material at station L4 has been analysed from March to December. The average concentration of amino acid nitrogen in Calanus was 7·7% of the dry body weight and accounted for 83% of the total nitrogen. The average level of amino acid nitrogen in the particulate material was 11·9 μg/1. and accounted for 54% of the total nitrogen.The relative quantities of amino acids in Calanus remained remarkably constant throughout the year. The relative quantities of amino acids in particulate material were more variable.The rate of respiration of Calanus measured at 8°C varied from 31 μl. O2/mg. dry body weight/day in winter (December–February) to 79 μl. O2/mg dry body weight/day in summer (April–August).Starving winter Calanus lost 1·8% and starving summer Calanus 2·1% of their dry body weight as amino acids each day. In order to replenish its daily losses of amino acids winter Calanus must sustain a filtering rate of about 30 ml./animal/day: the corresponding value in summer is greater than 50 ml./animal/day.The amino acid composition of Skeletonema costatum is so close to that of the particulate material in the sea, that, as far as amino acids are concerned, Calanus would gain no nutritional advantage by selecting the diatom in preference to the amino acid containing fraction of particulate material as a whole.

Amino acid composition, protein content and accurate nitrogen-to-protein conversion factor for sheepgrass (Leymus chinensis)

Botany ◽  
2020 ◽  
Vol 98 (3) ◽  
pp. 137-146 ◽  
Author(s):  
Qingfen Zhang ◽  
Dongmei Qi ◽  
Xiaobing Dong ◽  
Xiaoxia Li ◽  
Liqin Cheng ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Composition ◽  
Protein Content ◽  
Acid Composition ◽  
Total Nitrogen ◽  
Total Protein ◽  
Conversion Factor ◽  
Leymus Chinensis ◽  
Total Protein Content ◽  
Protein Nitrogen

The protein content of plants is commonly estimated by multiplying the total nitrogen content (Kjeldahl; KN) by a nitrogen-to-protein conversion factor of 6.25. This method is based on the incorrect assumption that all nitrogen in the ammonia/ammonium and organic substances in plants is protein nitrogen, usually resulting in overestimation of protein content. We have examined amino acid composition, amino acid nitrogen, total nitrogen (KN), and actual protein content (AP) determined from amino acid residues in 16 accessions of perennial sheepgrass (Leymus chinensis (Trin.) Tzvelev). We determined a new nitrogen-to-protein conversion factor, kP, as the ratio of AP to KN, and applied this factor to estimate the total protein content (TP) as KN × kP. The non-protein nitrogen accounted for 40.5% to 62.4% of the total nitrogen. The average kP value was 3.17 overall, 3.20 in the accessions sampled at the jointing stage, and 3.15 in the accessions sampled at the flowering stage. The TP, calculated as KN × 3.17, was about half that of crude protein contents, calculated as KN × 6.25. Our study suggests that the AP-based kP of 3.17 can be used to more accurately estimate the total protein content in sheepgrass.

scholarly journals Characteristic of the nutritive value of the protein from rye caruopses. I. Amino acid composition of protein and the nitrogen forms in the caryopses of ten rue varieties from the breeding collection

2015 ◽  
Vol 27 (1) ◽  
pp. 105-114 ◽  
Author(s):  
R. Kubiczek ◽  
M. Rakowska
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Protein Content ◽  
Acid Composition ◽  
Nutritive Value ◽  
Dry Weight ◽  
High Protein ◽  
Soluble Nitrogen ◽  
Protein Nitrogen

Total and soluble nitrogen, protein and non-protein -nitrogen was determined as well as the amino acid composition of the caryopses of ten rye varieties including three bred in Poland and cultivated on a commercial scale: 'Dańkowskie Złote', 'Dańkowskie Selekcyjne' and 'Borkowskie Tetra'. and seven foreign varieties characterized by a high total protein content (11.9-16.4% in dry weight). In the varieties examined the amount of protein nitrogen increased in the same degree as did the content of total nitrogen. The amino acids limiting the nutritive value of the protein in rye caryopses were mostly lysine and methionine, and in the varieties with high protein content tryptophan. The low-protein varieties had a relatively higher content of lysine, sulphur amino acids, tryptophan and other amino acids (as % of protein) than the high protein ones, but their absolute amino acid content (as % of dry weight) was lower.

ORGANIC NITROGEN DISTRIBUTION IN SELECTED PEATS AND PEAT FRACTIONS

1978 ◽  
Vol 58 (2) ◽  
pp. 237-249 ◽  
Author(s):  
F. J. SOWDEN ◽  
H. MORITA ◽  
M. LEVESQUE
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Acid Amide ◽  
Amino Sugar ◽  
The Other ◽  
Total N ◽  
Mesh Material ◽  
The Individual

The nitrogenous products formed by 6 N HCl hydrolysis of a variety of peats including a cultivated mesic profile, a virgin humic profile, a sedge, a woody and a sphagnum fibric peat were studied. Peat fractions separated according to particle size, woody and herbaceous materials isolated from a peat sample, and Typha and Carex plants growing on peat soils were also analyzed. Of the two profiles examined, the cultivated mesic peat showed significant quantitative changes in the content of individual amino acids throughout the profile. Also the amino sugar and amino acid N increased to a maximum, then decreased. On the other hand, the virgin humic peat profile exhibited random variations in the content of the individual amino acids and in the amount of amino acid N. Of the other peats examined, the fibric sphagnum had the highest percentage of amino acid N. Among the separates, the 100- to 200-mesh material had the highest proportion of amino acid N. The amino acid composition of the plant remains from the peat was similar to that of the peat from which it was isolated. The amino acid composition of the Typha and Carex plants was different from that of peat in that 75% of their total N content could be accounted for on the basis of amino acid, amide and amino sugar N. The amounts of hydroxyproline and the amino sugars in peats vary more than that of the amino compounds. In contrast to inorganic soils, which tend to have a similar amino acid composition, these limited data suggest that the amino acid and amino sugar contents of peats may be characteristic of individual bogs.

Studies in the biochemistry of cirripede eggs III. Changes in the amino-acid composition during development of Balanus balanoides and B. balanus

1967 ◽  
Vol 47 (1) ◽  
pp. 171-180 ◽  
Author(s):  
H. Barnes ◽  
R. Evens
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Rapid Development ◽  
Calanus Finmarchicus ◽  
Protein Nitrogen ◽  
Early Stages ◽  
The Difference ◽  
Balanus Balanoides

The amino-acid composition of Balanus balanoides (L.) and B. balanus (L.) da Costa eggs during their development has been investigated. Protein accounts for 70–80% of the dry matter. The amino-acid composition of the eggs is similar to that reported for Calanus finmarchicus, for which reliable information is available. Loss of all amino acids takes place during development, but the relative amounts of glycine and alanine increase in the late stages. The rates of loss are far greater in B. balanus, where the eggs themselves develop more rapidly. In B. balanoides there is a distinct ‘ arrest’ in the rate of loss of amino acids at the H-stage; this is coincident with a similar arrest in the loss of other metabolites and in development. Loss of nitrogen from the eggs has been measured directly and the results compared with the values calculated from the analyses. In the early stages the agreement is good if allowance is made for the difference in temperature between the elution experiments and the natural environment.Data have already been presented (Barnes, 1965; Dawson & Barnes, 1966) on the major biochemical constituents of the eggs of two common cirripedes, Balanus balanoides and B. balanus, and on changes in these constituents during development. It has been shown that protein nitrogen is lost throughout development and that the rate of this loss is greatest during the early stages; also that nitrogen utilization relative to that of carbohydrate is greater in B. balanus. The more rapid development of the eggs of the latter species gives rise to a greater rate at which all substrates are utilized, but the proportions disappearing—relative to the initial quantities—are not widely different; rather more is lost in the species that develops more rapidly.

Effects of Nitrogen Source and Concentration on the Free Amino Acid Composition of Developing Wheat Grains

1990 ◽  
Vol 17 (2) ◽  
pp. 199 ◽  
Author(s):  
C Blumenthal ◽  
JW Lee ◽  
EWR Barlow ◽  
IL Batey
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Ammonium Nitrate ◽  
Amino Acid Composition ◽  
Free Amino Acid ◽  
Acid Composition ◽  
Free Amino ◽  
Amino Nitrogen ◽  
Grain Protein ◽  
Protein Nitrogen

Detached wheat heads (7 days post-anthesis) were grown in liquid culture containing nitrogen concentrations of 0.025% or 0.1% in the form of glutamine, ammonium nitrate or asparagine. With each form of the nitrogen, increasing the concentrations of nitrogen in the culture medium led to increases in the total nitrogen and the non-protein nitrogen in the grain. Protein contents (N × 5.7) were approximately 16% and 21% on a dry weight basis in the low and high treatments respectively for all nitrogen sources. Amino acids from the endosperm cavity, the ethanol-soluble extract of the grain, and the grain protein were analysed by HPLC techniques to define the site of transfer between amino acid forms. The results indicated that amino nitrogen from glutamine, ammonium nitrate, or asparagine enters the grain and is found in the endosperm cavity fluid mainly in the form of glutamine, alanine and, to a lesser extent, aspartate (including asparagine). These amino acids are then converted into the various other amino acids required for protein synthesis, as is demonstrated by the increases found in the others in the ethanol-soluble free amino acid fraction with different nitrogen regimes. These variations in the composition of the free amino acids occurred without altering the amino acid composition of the protein component of the grain.

The Catabolism of Nitrogen Compounds in Dendrostomun cymodoceae Edmonds (Sipunculoidea)

1957 ◽  
Vol 8 (2) ◽  
pp. 131 ◽  
Author(s):  
SJ Edmonds
Keyword(s):  
Uric Acid ◽  
Amino Acid ◽  
Total Nitrogen ◽  
Ammonia Nitrogen ◽  
Nitrogen Compounds ◽  
Protein Nitrogen ◽  
Urea Nitrogen ◽  
Amino Acid Nitrogen ◽  
Sipunculus Nudus

The total non-protein nitrogen in the excretory products of fasting specimens of Dendrostomum cymodoceae Edmonds was found to be 1.18-1.40 mg N/100 g wet wt./24 hr. Of the total nitrogen, 83-90 per cent. was excreted as ammonia nitrogen, 4-6 percent, as urea nitrogen, 0-4 percent. as amino acid nitrogen, and none as uric acid; 89-94 percent. of the nitrogen was thus accounted for. The results are compared with the corresponding values obtained by other workers for Sipunculus nudus and some other invertebrates.

Preliminary study on the use of different methods for determining the proportion of bacterial nitrogen in the total nitrogen of rumen contents

1973 ◽  
Vol 81 (1) ◽  
pp. 1-7 ◽  
Author(s):  
J. Anna Nikolić ◽  
M. Jovanović
Keyword(s):  
Amino Acid ◽  
Nucleic Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Total Nitrogen ◽  
Total Protein ◽  
Energy Content ◽  
Diaminopimelic Acid ◽  
Bacterial Protein ◽  
Digestible Energy

SummaryThree different methods have been used to estimate the contribution of bacterial nitrogen to the total nitrogen in rumen digesta from calves receiving ground diets containing different levels of digestible energy and in which part of the nitrogen was supplied as urea. The method based on the ratio of 2, 6-diaminopimelic acid (DAP)-N to total N for rumen contents and rumen bacteria was not successful because the bacterial fraction isolated from pooled rumen contents contained a similar concentration of DAP to whole rumen digesta. The main source of error in the method based on the nucleic acid N/total non-NH3-N ratio for whole rumen contents and bacteria was probably the variability in the ratio for bacteria growing under different conditions. The method utilizing differences in the amino acid composition of the diets, a bacterial fraction and rumen content estimates bacterial protein rather than bacterial nitrogen. The chief limitation is the different rate of degradation of different dietary proteins. Bearing in mind these limitations calculations by the nucleic acid method gave mean values of 61–94 % bacterial nitrogen in the total nitrogen of rumen contents 3 h after feeding four different diets. Values recorded by the amino acid composition method varied between 66 % and 82 % bacterial protein N in the total protein N of rumen contents. The proportional contribution of bacteria increased as the digestible energy content of the diet was decreased in both cases. However, since the ruminal total protein N concentration fell as the digestible energy content of the diet was reduced, the actual concentration of bacterial protein N decreased with decrease in dietary digestible energy.

The amino acid composition of cat (Felis catus) hair

1998 ◽  
Vol 67 (1) ◽  
pp. 165-170 ◽  
Author(s):  
W. H. Hendriks ◽  
M. F. Tarttelin ◽  
P. J. Moughan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Total Nitrogen ◽  
Compartmental Model ◽  
Performic Acid ◽  
Cysteic Acid ◽  
Hair Colour ◽  
Non Linear

AbstractThe amino acid composition of cat hair was determined by conventional 24-h acid hydrolysis and non-linear least-squares extrapolation to time zero of the amino acid composition data from a series of hydrolysis intervals. Twenty-five individual samples of cat hair, consisting of four colours, were also analysed (24-h hydrolysis) to determine if there was an effect of hair colour on amino acid composition. Amino acids were determined following HCl hydrolysis (6 mol/l) with cysteine and methionine determined by performic acid oxidation of the sample prior to hydrolysis.There was no significant (P > 0·05) effect of hair colour on the amino acid composition of cat hair. The non-linear compartmental model used to determine the amino acid composition of cat hair took into account the simultaneously occurring processes of hydrolysis and degradation of amino acids over time. The amino acids cysteic acid, methionine-sulphone, threonine and serine exhibited high loss rates during 6 molll HCl hydrolysis while the peptide bonds involving valine and leucine were slowly hydrolysed. Amino acid nitrogen accounted for 0·94 of the total nitrogen in cat hair when determined by conventional 24-h hydrolysis and 0·99 of the total nitrogen when the compartmental model was applied. The average nitrogen proportion in cat hair protein was found to be 0·175. The amino acid composition of cat hair protein is comparable with that of dog, horse, sheep and human hair although the proline content of cat hair protein appears to be lower than that in the other species.

Sign in / Sign up

Export Citation Format

Share Document