Effect of nitrogen nutrition on distribution of photosynthetically incorporated 14CO2 in Lolium perenne

1975 ◽  
Vol 53 (3) ◽  
pp. 237-242 ◽  
Author(s):  
A. L. Barta
Keyword(s):  
Amino Acids ◽  
Soluble Fraction ◽  
Nitrogen Nutrition ◽  
Insoluble Fraction ◽  
Plant Metabolism ◽  
Ammonium Toxicity ◽  
Nutrient Culture ◽  
N Deficiency ◽  
C Metabolism ◽  
Percentage Conversion

Ryegrass plants grown in low NO3-N, high NO3-N, or high NH4-N nutrient culture were labeled by assimilation of 14CO2 by the tops. Plants were harvested 2, 6, and 24 h after labeling and percentage, 14C incorporation was measured in ethanol-soluble, chloroform-soluble, and ethanol-insoluble fractions of leaves, stems, and roots. Low N roots accumulated the greatest and high NH4-N roots accumulated the least 14C at the end of 24 h. Low NO3-N plants had higher levels of ethanol-soluble 14C and lower chloroform-soluble and ethanol-insoluble 14C than high NO3-N plants. Analysis of the ethanol-soluble fraction revealed higher, 14C content in sugars and less in amino acids in low NO3-N plants than in high NO3-N plants. Labeling patterns in high NH4-N plants suggested incipient ammonium toxicity since 14C metabolism was retarded, yet the plants showed no visual toxicity symptoms. When using percentage conversion of label from the ethanol-soluble to ethanol-insoluble fraction as a criterion for plant metabolism, roots appeared to be more sensitive to N deficiency than were tops. This result implies that reduced root growth and (or) function (nutrient uptake) may be one of the first effects of N deficiency.

Studies in the Natural Coating of Apples IV. the Nature of Cutin

1959 ◽  
Vol 12 (2) ◽  
pp. 175 ◽  
Author(s):  
FE Huelin
Keyword(s):  
Amino Acids ◽  
Alkaline Hydrolysis ◽  
Soluble Fraction ◽  
Protein A ◽  
Insoluble Fraction ◽  
Water Soluble ◽  
Water Soluble Fraction

Cutin purified with snail gut extract yielded, on alkaline hydrolysis, ethersoluble acids, a water-soluble fraction containing carbohydrates, and an insoluble fraction containing protein. A number of sugars and amino acids were identified in the acid hydrolysates of the last two fractions.

scholarly journals The influence of the gut microflora on the digestion of dietary and endogenous proteins: studies of the amino acid composition of the excreta of germ-free and conventional chicks

1974 ◽  
Vol 32 (3) ◽  
pp. 625-637 ◽  
Author(s):  
D. N. Salter ◽  
Rosemary J. Fulford
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Soluble Fraction ◽  
Insoluble Fraction ◽  
Freeze Dried ◽  
True Digestibility ◽  
Egg Albumen ◽  
Endogenous Proteins

1. To assess the part played by the microflora in the digestion of proteins, the amino acid composition of the excreta and the apparent and true digestibilities of individual amino acids were measured in germ-free (GF) and conventional (CV) chicks.2. Three diets were used: diet 1, nitrogen-free; diet 2,280 g protein/kg as (g/kg): casein 80, gelatin 100 and freeze-dried egg albumen 100 and diet 3,280 g protein/kg as diet 2 but with heat-damaged instead of freeze-dried egg albumen. Half of the GF and half of the CV chicks received the N-free diet in the first 7 d of test and the other half of each group received either diet 2 or diet 3. In the second 7 d test period those chicks which had been given the N-free diet received either diet 2 or diet 3 while those which had been given protein diets received the N-free diet. Total amino acids were measured in hydrolysates of the soluble and insoluble fractions of the excreta collected in the last 3 d of each test period.3. The amino acid composition of the soluble fraction of the excreta of chicks given either diet 2 or diet 3 differed markedly from that of chicks given the N-free diet. The amino acid composition of the insoluble fraction of the excreta of chicks given diet 2 was similar to that of chicks given the N-free diet, whereas that of chicks given diet 3 was markedly different and resembled egg albumen in composition.4. In the soluble fraction of excreta from CV chicks given diets 1 and 2 the proportions of threonine, serine and glucosamine were lower and those of methionine, leucine, isoleucine and phenylalanine were higher than in those from GF chicks, particularly on diet 1. In the insoluble fraction of excreta from CV chicks given these two diets, compared with GF chicks, there were lower proportions of serine and proline and higher proportions of cysteic acid and lysine, the latter particularly with diet 1.5. Lower proportions of threonine, serine and glucosamine were also observed in the soluble fractions of excreta from the CV chicks given diets 1 and 3, compared with GF chicks, whereas the proportion of glutamic acid was higher. With these two diets the insoluble fraction from CV chicks contained a higher proportion of alanine. In each instance the environmental effect was greater with diet 1.6. No effect of environment on either apparent or true digestibility of individual dietary protein amino acids was demonstrated, with the exception of threonine in diet 2, the true digestibility of which was higher in GF than in CV chicks.7. It was concluded that the gut microflora of the chick had little influence on the digestion of the proteins in the diets tested, but may serve an important role in the degradation of endogenous proteins and the recycling of N.

scholarly journals The radical scavenging activity of 2-2’ diphenyl -1- picrylhydrazil (DPPH) on the methanol extracts and Ethyl acetate fractions of red dragon fruit peel  (Hylocereus polyrhizus (F.A.C.Weber) Britton dan Rose)

2017 ◽  
Vol 9 (1) ◽  
pp. 79
Author(s):  
Sri Wahdaningsih ◽  
Subagus Wahyuono ◽  
Sugeng Riyanto ◽  
Retno Murwanti
Keyword(s):  
Antioxidant Activity ◽  
Ethyl Acetate ◽  
Methanol Extract ◽  
Soluble Fraction ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Insoluble Fraction ◽  
Fruit Peel ◽  
Activity Test ◽  
Dragon Fruit

<p> </p><p>Red dragon fruit (<em>H. Polyrhizus</em>) is one of the the plants that has a great potential as natural antioxidant. This study tested the activity of radical scavenging of 2-2' diphenyl -1- pikril hidrazil (DPPH) in the methanol extract, as well as in the soluble and insoluble fractions of ethyl acetate of red dragon fruit peel. This research is carried out through various stages, such as: extraction and fractionation to obtain both insoluble fraction and soluble fractions of ethyl acetate. Antioxidant activity test is conducted by the method of thin layer chromatography and spectrophotometry.<strong> </strong>Antioxidant activity test, IC<sub>50 </sub>values of methanol extract, ethyl acetate soluble fraction, and insoluble fraction of ethyl acetate had been obtained consecutively as much as 241.19 µg /mL, 8.34  µg/mL, 46.84 µg/mL. The soluble fraction of ethyl acetate had greater antioxidant activity compared to the methanol extract and the insoluble fractions of ethyl acetate.</p>

scholarly journals The GC-TOF/MS-based Metabolomic Analysis Reveals Altered Metabolic Profiles in Nitrogen-Deficient Leaves and Roots of Tea Plants (Camellia sinensis L.)

2021 ◽  
Author(s):  
Zheng-He Lin ◽  
Chang-Song Chen ◽  
Qiu-Sheng Zhong ◽  
Qi-Chun Ruan ◽  
Zhi-Hui Chen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Organic Acids ◽  
N Fertilizer ◽  
Metabolic Profiles ◽  
Tea Leaves ◽  
N Deficiency ◽  
Leaves And Roots ◽  
Tea Plants ◽  
Potential Biomarkers ◽  
Tof Ms

Abstract Background: Nitrogen (N) fertilizer is commonly considered as one of the most omportant limiting factors in the agricultural production. As a result, modern tea production, a large amount of N fertilizer is used to improve the yield. Unfortunately, the large amount of N fertilizer input has led to increased plant nitrogen-tolerance and decreased amplitude of yield improvement, which results in significant N loss, energy waste and environment pollution.However, the effects of N-deficiency on the metabolic profiles of leaves and roots are not well understood.Results: In the study, seedlings of Camellia sinensis (L.) O. Kuntze cv. Chunlv 2 were treated with 3 mM NH4NO3（as Control）or without NH4NO3（as N-deficiency）for 4 months by sandy culture. The results suggested the N-deficiency induced tea leaf chlorosis, impaired biomass accumulation, decreased the leaf chlorophyll content and N absorption compared to Control. The untargeted metabolomics based on GC-TOF/MS approach revealed discrimination of the metabolic profiles between N-deficient tea leaves and roots. The identification and classification of the altered metabolites indicated the N deficiency upregulated the relative abundances of most phenylpropanoids, organic acids while downregulated the relative abundances of most amino acids in the tea leaves. Differentially, N-deficiency induced the accumulation of most carbohydrates, organic acids and amino acids in the tea roots. The potential biomarkers screened in the N-deficient leaves compared to Control reflected the N deficiency reduced the tea quality. Unlike the N-deficient leaves, the potential biomarkers in the N-deficient roots implied an improved stress response. Conclusions:The results demonstrated the N deficiency had different effects on the primary and secondary metabolic alteration of tea leaves and roots. The findings of the study will facilitate a comprehensive understanding of the N-deficient tea plants and provide a valuable reference for the optimized N nutrient management in the tea plantations.

Regulation of HSP25 expression and phosphorylation in functionally overloaded rat plantaris and soleus muscles

2006 ◽  
Vol 100 (2) ◽  
pp. 451-456 ◽  
Author(s):  
Kimberly A. Huey
Keyword(s):  
Heat Shock ◽  
Muscle Hypertrophy ◽  
Soluble Fraction ◽  
Insoluble Fraction ◽  
Cytoskeletal Proteins ◽  
Time Dependent ◽  
Time Points ◽  
Hindlimb Muscle ◽  
Muscle Loading ◽  
Muscle Remodeling

Functional overload (FO) is a powerful inducer of muscle hypertrophy and both oxidative and mechanical stress in muscle fibers. Heat shock protein 25 (HSP25) may protect against both of these stressors, and its expression can be regulated by changes in muscle loading and activation. The primary purpose of the present study was to test the hypothesis that chronic FO increases HSP25 expression and phosphorylation (pHSP25) in hypertrophying rat hindlimb muscle. HSP25 and pHSP25 levels were quantified in soluble and insoluble fractions of the soleus and plantaris to determine whether 3 or 7 days of FO increase translocation of HSP25 and/or pHSP25 to the insoluble fraction. p38 protein and phosphorylation (p-p38) was measured to determine its association with changes in pHSP25. HSP25 mRNA showed time-dependent increases in both the soleus and plantaris with FO. Three or seven days of FO increased HSP25 and pHSP25 in the soluble fraction in both muscles, with a greater response in the plantaris. In the insoluble fraction, HSP25 was increased after 3 or 7 days in both muscles, whereas pHSP25 was only increased in the 7-day plantaris. p38 and p-p38 increased in the plantaris at both time points. In the soleus, p-p38 only increased after 7 days. These results show that FO is associated with changes in HSP25 expression and phosphorylation and suggest its role in the remodeling that occurs during muscle hypertrophy. Increases in HSP25 in the insoluble fraction suggest that it may help to stabilize actin and/or other cytoskeletal proteins during the stress of muscle remodeling.

Fractionation of Rubber

1941 ◽  
Vol 14 (1) ◽  
pp. 1-14 ◽  
Author(s):  
George F. Bloomfield ◽  
Ernest Harold Farmer
Keyword(s):  
Molecular Weight ◽  
Soluble Fraction ◽  
Insoluble Fraction ◽  
The Other ◽  
Major Fraction ◽  
Low Concentrations ◽  
Fractional Dissolution ◽  
Judicious Choice ◽  
Hydrocarbon Molecules ◽  
Soluble Fractions

Abstract Latex rubber which has been purified to the point at which it contains an insignificant amount of nitrogen can be separated by fractional dissolution in a mixture of petroleum and acetone into a series of hydrocarbon fractions of decreasing solubility and increasing molecular magnitude. All these fractions except the highest are soluble in petroleum and in benzene. Crepe rubber, on the other hand, appears invariably to contain a small, most-soluble fraction of oxygenated rubber, and a small similar quite insoluble fraction of material of high molecular weight. Between these extremes the rubber can be divided into fractions of increasing molecular weight, although, up to the present, about 70 per cent of the total rubber has appeared in a single fraction. It may be possible later, by judicious choice of another pair of solvents, to resolve this major fraction into a series of subfractions. Kemp and Peters refer to the effect of polar nonsolvents in reducing the viscosity of rubber solutions and also in assisting to bring gel rubber into solution, phenomena to which the polar molecules conceivably contribute by countering the forces of association between the rubber molecules. The present series of fractionations was conducted throughout in the presence of a polar nonsolvent (acetone), and hence may be considered to approach towards a separation of true rubber molecules as distinct from molecular aggregates. It is found, however, that, whereas the more soluble fractions of acetone-extracted crepe rubber contain small proportions of nitrogen, the least soluble fractions contain substantial proportions. Any effect which the nitrogenous material may have in assisting to link together hydrocarbon molecules to which it is attached, i. e., in contributing to the high-molecular condition of a portion of natural rubber, remains at present uncertain in character. The fractions of rubber, and especially the higher ones, show a strong tendency to become insoluble when they have once been freed from the last traces of solvent. It seems doubtful whether the decreased solubility is due to oxygen as it would require to be effective at exceedingly low concentrations.

Investigations on the root nodule bacteria of leguminous plants: XIX. Influence of various factors on the excretion of nitrogenous compounds from the nodules

1937 ◽  
Vol 27 (3) ◽  
pp. 332-348 ◽  
Author(s):  
Artturi Ilmari Virtanen ◽  
Synnöve von Hausen ◽  
Tauno Laine
Keyword(s):  
Amino Acids ◽  
Nitrogen Fixation ◽  
Root Nodule ◽  
Nitrogen Nutrition ◽  
Nitrogen Compounds ◽  
Nodule Bacteria ◽  
Fixed Nitrogen ◽  
Nitrogenous Compounds ◽  
Primary Products ◽  
Equal Effectiveness

1. It has been shown experimentally that the excretion of nitrogen noted by us in cultures of inoculated legumes takes place from the nodule bacteria, probably from the intranodular ones, and not from the roots. No excretion of amino acids occurs in cultures of uninoculated legumes growing on nitrate nitrogen.2. Our earlier hypothesis that the legumes receive their nitrogen nutrition from the nodules in the form of organic nitrogen compounds, particularly amino acids, is in perfect accord with our new observations concerning the process of excretion. All facts indicate that the amino acids concerned are primary products of the nitrogen fixation, and not breakdown products of proteins. Bond's valuable work along quite different lines produced results which support this conclusion. He, however, did not study the chemical nature of the nitrogen compounds in question.3. The excretion of nitrogen occurs in media capable of absorbing the excreted nitrogen compounds (cellulose, kaolin, sand, soil). The demonstration of the excretion is not possible in water cultures except when very large quantities of water are used. On the basis of these facts a hypothesis is advanced to explain the nature of the excretion.4. The term total fixed nitrogen has been used as an expression for the extent of nitrogen fixation, while the term extent of excretion is employed to indicate that percentage of the total fixed nitrogen which is excreted from the nodules.5. The extent of excretion depends largely on the strain used for inoculation. With strains of apparently equal effectiveness in nitrogen fixation, the extent of excretion may vary considerably, so that actually such strains differ in their effectiveness.

scholarly journals On the Nitrogen Nutrition of Silage Strains of Lactic Acid Bacteria

1966 ◽  
Vol 19 (1) ◽  
pp. 105 ◽  
Author(s):  
CJ Brady
Keyword(s):  
Amino Acids ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Free Amino Acids ◽  
Free Amino ◽  
Nitrogen Nutrition ◽  
Synthetic Medium ◽  
Post Harvest ◽  
Synthetic Media ◽  
Time Of Harvest

Consideration is given to the adequacy of the free amino acids in plant juices at the time of harvest as nitrogen substrate for strains of lactic acid bacteria isolated from silage. The requirements of several strains of the bacteria for free amino acids in synthetic media were compared with the concentration of these acids in the liquid phase of plants at the time of harvest; this comparison suggested that several amino acids, and particulady lysine, may at times be rate.limiting. Ethanolic extracts of plants, sampled before and after a period of post-harvest wilting, were assayed as nitrogen substrates for the bacteria. A marked response to additions of lysine, some response to arginine, and evidence of deficiency of other acids were noted. The importance of post-harvest proteolysis to the amino acid nutrition of the bacteria in the silage environment is discussed. Certain fractions of the plant extracts were found to promote early growth of the bacteria in the synthetic medium, and the distribution of this activity in different fractions is described.

Formate metabolism and betaine formation in healthy and rust-infected wheat

1970 ◽  
Vol 48 (4) ◽  
pp. 803-811 ◽  
Author(s):  
Margaret S. Bowman ◽  
R. Rohringer
Keyword(s):  
Amino Acids ◽  
Nucleic Acid ◽  
Stem Rust ◽  
Betaine Lipids ◽  
Dark Metabolism ◽  
Synthesis Activity ◽  
C Metabolism ◽  
Wheat Leaves ◽  
Wheat Tissues ◽  
Formate Metabolism

Formate-14C was fed to detached primary leaves of wheat and the distribution of activity among various fractions was examined after 2 to 26 h of metabolism in the light or 4 h of metabolism in the dark.All samples contained activity in free neutral, acidic, and basic compounds. The radioactive metabolites in the basic fraction were examined in detail. Initially, in the light, glutamate, aspartate, serine, and an unknown, chromatographically similar to, but not identical with histidine, contained most of the activity. Activity in betaine increased with time until, at 26 h, it contained nearly half of the activity in this fraction. Following dark metabolism, most of the activity resided in glutamate and serine. Glycine was not radioactive, and most of the activity in serine resided in carbon 3, indicating that formate served as a precursor of C1-units that were used for serine synthesis. Activity was also detected in a number of other amino acids and choline, both in the light and dark.A comparison of formate-14C metabolism in the dark in stem rust resistant and susceptible wheat leaves revealed that betaine, lipids, nucleic acid bound adenine and guanine, and a protein-containing residue from rust-infected susceptible leaves contained much more activity than the corresponding components from healthy susceptible or from healthy or rust-infected resistant leaves.Activity from glycine-2-3H, methionine-14CH3, serine-3-14C, ethanolamine-1,2-14C, and choline-14CH3 was incorporated into betaine in the dark, but was not detected in sarcosine or dimethylglycine. These results support the view that betaine was synthesized from glycine via serine, ethanolamine, and choline with methionine as the methyl donor, and not by direct N-methylation of glycine.Betaine-14CH3 was translocated but not metabolized in healthy or rust-infected primary leaves of wheat, or in aerial portions of adult wheat plants. In these wheat tissues, betaine would thus appear to be a metabolic end product.

Production, isolation and identification of low molecular mass peptides from blue cheese by high performance liquid chromatography

1991 ◽  
Vol 58 (3) ◽  
pp. 363-372 ◽  
Author(s):  
Dolores Gonzalez de Llano ◽  
M. Carmen Polo ◽  
Mercedes Ramos
Keyword(s):  
Amino Acids ◽  
Molecular Mass ◽  
High Performance ◽  
Phosphotungstic Acid ◽  
Soluble Fraction ◽  
Water Soluble ◽  
Isolation And Identification ◽  
Blue Cheese ◽  
Water Soluble Fraction ◽  
Gel Permeation

SummaryThe blue cheese nitrogenous fractions soluble in water and in 5% phosphotungstic acid (PTA) were analysed by HPLC after 3–180 d ripening. In the water-soluble fraction, in addition to four or five major peaks corresponding to amino acids, there were many minor peaks, which increased during ripening. The low molecular mass peptides, soluble in 5% PTA, showed ripening-induced increments. A method combining precipitation with 5% PTA, gel permeation and subsequent HPLC was used to isolate some peptides of cheese. Four peptides containing between seven and ten residues were isolated and their amino acid composition and N-terminal residues determined.

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