DISTRIBUTION OF NITROGEN IN THE BLACK SOLONETZIC AND BLACK CHERNOZEMIC SOILS OF ALBERTA

1971 ◽  
Vol 51 (2) ◽  
pp. 185-193 ◽  
Author(s):  
S. U. KHAN ◽  
F. J. SOWDEN

More N was brought into solution by hydrolysis with 6 N HCl from the Ah horizons of a Black Solonetz and a Black Solod than from the Ah horizon of a Black Chernozem soil of Alberta. The percentages of total N represented by the ammonium-N, amino acid-N and amino sugar-N were similar for the three soils. The proportion of soil-N present as amino acid-N and amino sugar-N decreased and that of ammonium-N increased with depth in all three profiles. The acid hydrolysis of the water-extract obtained from Ah horizon of the Black Solonetz released more (ammonium + amino acid + amino sugar)-N than did that of the Ah horizons of the other two soils. The humic acid fractions obtained from Ah horizons contained more total N than did the humic acids extracted from the B horizons of the three soils. While the proportions of N accounted for as (ammonium + amino acid + amino sugar)-N in the humic acid fractions from Ah horizons of the soils were similar, they increased in the order Chernozem > Solod > Solonetz for the B horizons. In general, there were few noteworthy differences in the amino acid distribution between the three soils or between the various horizons of the same soil. The hydrolyzates of the water-extracts of Ah horizons showed higher values for the molar distribution of threonine, serine, glycine and alanine, and lower values for aspartic acid and glutamic acid than did the corresponding hydrolyzates of the soils; the amounts of free amino acids in these extracts were very small. There was little difference in the amino acid composition of the humic acid fractions obtained from the three soils or from the different horizons of the same soil; it was, in general, similar to that of the soils. The data indicate that differences in the salt regime in the Solonetzic, Solodic and Chernozemic soils do not result in the different kinds of nitrogenous organic matter.

1980 ◽  
Vol 60 (3) ◽  
pp. 541-548 ◽  
Author(s):  
M. SCHNITZER ◽  
D. A. HINDLE

Three humic and one fulvic acid were degraded by mild chemical oxidation with peracetic acid, with special emphasis on the effects of this type of oxidation on N-containing components. The different types of N that were considered were NH4+-N, amino acid-N, amino sugar-N, NO2−-N + NO3−-N, and by difference from total N, "unknown" N. The behaviour toward mild chemical oxidation of all four preparations was essentially similar: there were decreases in mino acid-N, amino sugar-N and "unknown" N, increases in NH4+-N, NO2−-N + NO3−-N with one material, and in N-gases. The "unknown" N was not inert. Between 16.6 and 59.1% of the latter appeared to be converted, as a result of mild chemical oxidation, to NH3 and N-gases which were expelled from the systems. The results presented provide an insight into what happens to N-containing humic components as a result of mild oxidation.


Some time ago, two of the authors of the present communication, in seeking a method for the separation of the amino-acids from the carbohydrates, found that under certain conditions the former could be readily separated in the form of the barium salts of their carbamates, a class of compounds originally described by Siegfried. As these carbamates, on heating with water, are readily decomposed into barium carbonate and the free amino-acid, it was suggested that a convenient method might be evolved, using the formation of these compounds as a basis, for the separation of the hydrolysis products of the proteins.* This suggestion was followed up, and a method was subsequently elaborated and applied to the separation of the hydrolysis products of gelatin by one of the authors in conjunction with Miss H. L. Kingston. Since the publication of the two papers just quoted, the researches on the use of the “carbamate method,” as it may be conveniently called, have been continued, and promise results, which may ultimately lead to a satisfactory separation of most of the hydrolysis products of the proteins when only relatively small amounts of material are available for investigation. During the course of this work the base, which is the chief subject discussed in this paper, was discovered.


1966 ◽  
Vol 19 (4) ◽  
pp. 667 ◽  
Author(s):  
DL Ingles

Sulphurous acid alone and in admixture with other stronger acids has been used to hydrolyse 5-amino, 5-N-cyclohexylamino, and 5-N-piperidino derivatives of 5-deoxy-l,2-O-isopropylidene-D-xylose. The bisulphite addition compounds of the corresponding amino sugars were thus isolated. Similarly, methyl 5-amino-5-deoxy- 2,3-O-isopropylidene-D-riboside was hydrolysed to yield the bisulphite addition compound of 5-amino-5-deoxy-D-ribose. Treatment of the bisulphite addition compound of 5-amino-5-deoxy-D-xylose with barium hydroxide gave the free amino sugar as a syrup in 96% yield. Removal of bisulphite from the addition compound of 5-X-cyclohexylamino-5-deoxy-D-xylose gave the free sugar in 30% yield together with an amino acid (XVI).


HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 796C-796
Author(s):  
Guihong Bi* ◽  
Carolyn Scagel ◽  
Lailiang Cheng ◽  
Leslie Fuchigami

June-budded `Nonpareil/Nemaguard' almond (Prunus dulcis (Mill) D.A. Webb) trees were fertigated with one of five nitrogen (N) concentrations (0, 5, 10, 15, or 20 mm) in a modified Hoagland's solution from July to September. In October, the trees were sprayed twice with either water or 3% urea, then harvested after natural leaf fall and stored at 2°C. Trees were destructively sampled during winter storage to determine their concentrations of amino acids, protein, and non-structural carbohydrates (TNC). Increasing N supply either via N fertigation during the growing season or with foliar urea applications in the fall increased the concentrations of both free and total amino acids, whereas decreased their C/N ratios. Moreover, as the N supply increased, the proportion of nitrogen stored as free amino acids also increased. However, protein was still the main form of N used for storage. The predominant amino acid in both the free and total amino-acid pools was arginine. Arginin N accounted for an increasing proportion of the total N in both the free and total amino acids as the N supply was increased. However, the proportion of arginine N was higher in the free amino acids than in the total amino acids. A negative relationship was found between total amino acid and non-structural carbohydrate concentrations, suggesting that TNC is increasingly used for N assimilation as the supply of N increases. Urea applications decreased the concentrations of glucose, fructose, and sucrose, but had little influence on concentrations of sorbitol and starch. We conclude that protein is the primary form of storage N, and that arginine is the predominant amino acid. Furthermore, the synthesis of amino acids and proteins comes at the expense of non-structural carbohydrates.


1996 ◽  
Vol 75 (2) ◽  
pp. 217-235 ◽  
Author(s):  
G. E. Lobley ◽  
A. Connell ◽  
D. K. Revell ◽  
B. J. Bequette ◽  
D. S. Brown ◽  
...  

AbstractThe response in whole-body and splanchnic tissue mass and isotope amino acid transfers in both plasma and blood has been studied in sheep offered 800 g lucerne (Medicago sutiva) pellets/d. Amino acid mass transfers were quantified over a 4 h period,by arterio-venous procedures, across the portal-drained viscera (PDV) and liver on day 5 of an intravenous infusion of either vehicle or the methylated products, choline (0.5 g/d) plus creatine (10 g/d). Isotopic movements were monitored over the same period during a 10 h infusion of a mixture of U-13C-labelled amino acids obtained from hydrolysis of labelled algal cells. Sixteen amino acids were monitored by gas chromatography-mass spectrometry, with thirteen of these analysed within a single chromatographic analysis. Except for methionine, which is discussed in a previous paper, no significant effects of choline plus creatine infusion were observed on any of the variables reported. Whole-body protein irreversible-loss rates ranged from 158 to 245 g/d for the essential amino acids, based on the relative enrichments (dilution of the U-13C molecules by those unlabelled) of free amino acids in arterial plasma, and 206-519 g/d, when blood free amino acid relative enrichments were used for the calculations. Closer agreement was obtained between lysine, threonine, phenylalanine and the branched-chain amino acids. Plasma relative enrichments always exceeded those in blood (P < 0.001), possibly due to hydrolysis of peptides or degradation of protein within the erythrocyte or slow equilibration between plasma and the erythrocyte. Net absorbed amino acids across the PDV were carried predominantly in the plasma. Little evidence was obtained of any major and general involvement of the erythrocytes in the transport of free amino acids from the liver. Net isotope movements also supported these findings. Estimates of protein synthesis rates across the PDV tissues from [U-13C] leucine kinetics showed good agreement with previous values obtained with single-labelled leucine. Variable rates were obtained between the essential amino acids, probably due to different intracellular dilutions. Isotope dilution across the liver was small and could be attributed predominantly to uni-directional transfer from extracellular sources into the hepatocytes and this probably dominates the turnover of the intracellular hepatic amino acid pools.


2014 ◽  
Vol 60 (No. 2) ◽  
pp. 63-68 ◽  
Author(s):  
J. Kaur ◽  
Singh JP

A long-term experiment was used to evaluate the effects of different nutrient management practices on the distribution of soil organic N fractions and their contribution to N nutrition of a rice-wheat system. Continuous rice-wheat cultivation for 13 years without any fertilization was unable to maintain total soil nitrogen level to its original level and resulted in a decrease at 8.3 mg N/kg/year. Likewise, amino acid N, amino sugar N, ammonia N, hydrolysable unknown N, total hydrolysable N and non-hydrolysable N decreased by 37.2, 29.6, 33.7, 10.4, 26.6 and 20.4%, respectively over their initial status. However, application of inorganic fertilizers alone or in combination with organic manures led to a marked increase in total N and its fractions. The increase in total N with the application of farmyard manure, press mud and green manure along with inorganic fertilizer over treatment with inorganic fertilizer alone was 23.1, 34.4 and 7.0%, respectively. These results imply that integrated use of inorganic fertilizers with organic manures represent a sound practice for sustaining N reserves in soil. On average, amino acid-N, amino sugar-N, ammonia-N and hydrolysable unknown-N constituted about 27.9, 10.7, 28.7 and 32.7% of the total hydrolysable-N, respectively.


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