scholarly journals Available versus digestible dietary amino acids

2012 ◽  
Vol 108 (S2) ◽  
pp. S298-S305 ◽  
Author(s):  
Shane M. Rutherfurd ◽  
Paul J. Moughan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Hydrolysis ◽  
Acid Content ◽  
Amino Acid Analysis ◽  
Amino Acid Content ◽  
Cysteic Acid ◽  
Processed Foods ◽  
Dietary Amino Acids ◽  
Available Lysine

Available amino acids are those absorbed from the gastrointestinal tract in a form suitable for body protein synthesis. True ileal digestible amino acids are determined based on the difference between dietary amino acid intake and unabsorbed dietary amino acids at the terminal ileum. The accuracy of ileal digestible amino acid estimates for predicting available amino acid content depends on several factors, including the accuracy of the amino acid analysis procedure. In heat processed foods, lysine can react with compounds to form nutritionally unavailable derivatives that are unstable during the hydrochloric acid hydrolysis step of amino acid analysis and can revert back to lysine causing an overestimate of available lysine. Recently, the true ileal digestible reactive (available) lysine assay based on guanidination has provided a means of accurately determining available lysine in processed foods. Methionine can be oxidised during processing to form methionine sulphoxide and methionine sulphone and cysteine oxidised to cysteic acid. Methionine sulphoxide, but not methionine sulphone or cysteic acid, is partially nutritionally available in some species of animal. Currently, methionine and cysteine are determined as methionine sulphone and cysteic acid respectively after quantitative oxidation prior to acid hydrolysis. Consequently, methionine and cysteine are overestimated if methionine sulphone or cysteic acid are present in the original material. Overall, given the problems associated with the analysis of some amino acids in processed foodstuffs, the available amino acid content may not always be accurately predicted by true ileal amino acid digestibility estimates. For such amino acids specific analytical strategies may be required.

scholarly journals Absorption of Chemically Unmodified Lysine from Proteins in Foods That Have Sustained Damage During Processing or Storage

2005 ◽  
Vol 88 (3) ◽  
pp. 949-954 ◽  
Author(s):  
Paul J Moughan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Hydrolysis ◽  
Acid Content ◽  
Amino Acid Analysis ◽  
Amino Acid Content ◽  
Food Proteins ◽  
New Compounds

Abstract When a food is processed or stored, amino acids can react with a number of chemical entities to produce new compounds that are often nutritionally unavailable to the consumer. During acid hydrolysis used in amino acid analysis, some of these compounds revert back to the parent amino acid, leading to errors in estimates of both the amino acid content of foods and amino acid digestibility. This is a particular concern for the amino acid lysine in damaged food proteins. Chemical assays have thus been developed to allow determination of unaltered or reactive lysine. However, there is evidence that, in damaged food proteins, not all of the reactive lysine is released during digestion and absorbed. The development and application of an assay for absorbed (ileal digestible) reactive lysine is discussed.

scholarly journals ANALISIS KOMPONEN ASAM AMINO IKAN LAYANG DELES (Decapterus Makrosoma) HASIL OLAHAN TRADISIONAL BERDASARKAN LAMA PENYIMPANAN

2019 ◽  
Vol 9 (2) ◽  
pp. 123-132
Author(s):  
Vhindra Engson Lumamuly ◽  
Nikmans Hattu ◽  
Semuel Unwakoly
Keyword(s):  
Amino Acids ◽  
Liquid Chromatography ◽  
Amino Acid ◽  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Acid Content ◽  
Amino Acid Content ◽  
Storage Period ◽  
Ultra Performance Liquid Chromatography ◽  
Amino Acid Concentrations

The aim of this study was to determine the amino acid composition of traditional processed Layang Deles fish (Decapterus macrosoma) which was stored for 2 months. Analysis of amino acid content using by Ultra Performance Liquid Chromatography (UPLC) instrument after content of water and lipid in sample was removed. The results of the analysis showed that there was a change in the concentration of 15 amino acids measured ranging from 85.17% to 2,873.42% in acid hydrolysis and 88.18% to 28.73% in alkaline hydrolysis. The biggest changes occurred in histidine, arginine and serine amino acid concentrations of 2,873.42%, 2,606.74% and 900.00% in acid hydrolysis and in amino acids serine, aspartic acid and histidine which were 88.17%, 62, 99% and 40.02% in alkaline hydrolysis. Based on the results of the research, it can be concluded that the processing of inmana fish with a storage period of 2 months affects the amino acid components of Layang Deles fish (Decapterus macrosoma).

scholarly journals The Chemical Composition of Wool II. Analysis of the Major Histological Components Produced by Ultrasonic Disintegration

1965 ◽  
Vol 18 (2) ◽  
pp. 353 ◽  
Author(s):  
JH Bradbury ◽  
GV Chapman ◽  
NLR King
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Chemical Composition ◽  
Acid Content ◽  
Amino Acid Content ◽  
Dichloroacetic Acid ◽  
Cysteic Acid ◽  
Cortical Cells ◽  
Isoleucine Leucine ◽  
Merino Wool

Ultrasonic disruption of powdered Merino wool in formic acid and dichloroacetic acid causes some protein to be dissolved, but the amino acid content of the residual wool is unchanged by the treatment. Cortical cells and disrupted cortical cells are found to have the same composition as the parent fibre, which is to be expected because the latter consists of about 90 % cortical cells. However, the cuticle of Merino wool is different in composition from the parent fibre, being richer in cysteic acid, serine, proline, glycine, valine, and cystine, and poorer in aspartic acid, threonine, glutamic acid, methionine, isoleucine, leucine, tyrosine, phenylalanine, and arginine than the whole fibre. Thus the cuticle is considerably less polar than the fibre as a whole. With the exceptions detailed below, it is found that the first group of amino acids listed above are classified as non a.helix.forming and the second group as a�helix� forming by Blout (1962). The exceptions are isoleucine and threonine, whilst arginine and glycine are not classified. It is therefore postulated that the cuticle is amorphous because of its high content of non a�helix.forming amino acids. The cuticle of Lincoln wool shows similar differences to those already given for Merino cuticle but, in addition, contains less lysine and histidine than the whole fibre.

scholarly journals The Effect of Hydrolysis Time on Amino Acid Analysis

2005 ◽  
Vol 88 (3) ◽  
pp. 888-893 ◽  
Author(s):  
Alison J Darragh ◽  
Paul J Moughan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Multiple Regression ◽  
Acid Content ◽  
Amino Acid Analysis ◽  
Bond Cleavage ◽  
Amino Acid Content ◽  
Correction Factors ◽  
Hydrolysis Time ◽  
Peptide Bond Cleavage

Abstract Determining the amino acid content of a protein involves the hydrolysis of that protein, usually in acid, until the protein-bound amino acids are released and made available for detection. Both the variability in the ease of peptide bond cleavage and differences in the acid stability of certain amino acids can significantly affect determination of a protein's amino acid content. By using multiple hydrolysis intervals, a greater degree of accuracy can be obtained in amino acid analysis. Correction factors derived by linear extrapolation of serial hydrolysis data are currently used. Compartmental modeling of the simultaneous hydrolysis (yield) and degradation (decay) of amino acids by nonlinear multiple regression of serial hydrolysis data has also been validated and applied to determine the amino acid composition of various biological samples, including egg-white lysozyme, human milk protein, and hair. Implicit in the routine application of serial hydrolysis in amino acid analysis, however, is an understanding that correction factors, derived either linearly or through the more accurate nonlinear multiple regression approach, need to be determined for individual proteins rather than be applied uniformly across all protein types.

Evaluation of seed amino acid content and its correlation network analysis in wild soybean (Glycine soja) germplasm in Japan

2021 ◽  
Vol 19 (1) ◽  
pp. 35-43
Author(s):  
Awatsaya Chotekajorn ◽  
Takuyu Hashiguchi ◽  
Masatsugu Hashiguchi ◽  
Hidenori Tanaka ◽  
Ryo Akashi
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acid ◽  
Acid Content ◽  
Free Amino ◽  
Glycine Soja ◽  
Wild Soybean ◽  
Amino Acid Content ◽  
Soybean Seeds ◽  
Free Amino Acid Content

AbstractWild soybean (Glycine soja) is a valuable genetic resource for soybean improvement. Seed composition profiles provide beneficial information for the effective conservation and utilization of wild soybeans. Therefore, this study aimed to assess the variation in free amino acid abundance in the seeds of wild soybean germplasm collected in Japan. The free amino acid content in the seeds from 316 accessions of wild soybean ranged from 0.965 to 5.987 mg/g seed dry weight (DW), representing a 6.2-fold difference. Three amino acids had the highest coefficient of variation (CV): asparagine (1.15), histidine (0.95) and glutamine (0.94). Arginine (0.775 mg/g DW) was the predominant amino acid in wild soybean seeds, whereas the least abundant seed amino acid was glutamine (0.008 mg/g DW). A correlation network revealed significant positive relationships among most amino acids. Wild soybean seeds from different regions of origin had significantly different levels of several amino acids. In addition, a significant correlation between latitude and longitude of the collection sites and the total free amino acid content of seeds was observed. Our study reports diverse phenotypic data on the free amino acid content in seeds of wild soybean resources collected from throughout Japan. This information will be useful in conservation programmes for Japanese wild soybean and for the selection of accessions with favourable characteristics in future legume crop improvement efforts.

scholarly journals 24-Epibrassinolide Restores the Synthesis of Proteins and Amino Acids in Brassica juncea L. Leaves Under Imidacloprid Stress

2017 ◽  
Vol 25 (2) ◽  
pp. 85-90 ◽  
Author(s):  
Anket Sharma ◽  
Vinod Kumar ◽  
Ashwani Kumar Thukral ◽  
Renu Bhardwaj
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Brassica Juncea ◽  
Total Protein ◽  
Acid Content ◽  
Soil Amendment ◽  
Insect Pests ◽  
Amino Acid Content ◽  
Total Proteins ◽  
Amino Acid Contents

Abstract Pesticides are applied to protect crops from a variety of insect pests but their application cause toxicity to plants that results, among others, in reduction of protein as well as amino acid contents. The present study is aimed at observing the effect of seed pre-soaking with 24-epibrassinolide (EBL) on the protein and amino acid content in the leaves of Brassica juncea L. grown in soil that is amended with pesticide im-idacloprid (IMI). Soil amendment with IMI resulted in a decrease in the contents in leaves of total proteins and 21 amino acids studied. Seed soaking with 100 nM of EBL resulted in the recovery of total protein as well as amino acid contents in leaves, when compared with plants grown in only IMI amended soils.

The Oocytes of the Goby Pomatoschistus minutus. III. Determination of Amino Acid Component

1980 ◽  
Vol 35 (11-12) ◽  
pp. 1094-1095
Author(s):  
Rüdiger Riehl
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Acid Content ◽  
Amino Acid Content ◽  
Acid Component ◽  
Pomatoschistus Minutus ◽  
Protein Amino Acids ◽  
Amino Acid Component

Abstract The oocytes of the marine goby Pomatoschistus minutus were analyzed for their amino acid content. Most of the amino acids exist as protein, only a little part is free or peptide-bound. Among the protein-bound amino acids, high levels of glutamic acid, proline, alanine, aspartic acid, valine and leucine were detected. These represent more than 60% of the protein amino acids. Among the free acids, glutamic acid, serine and alanine, are dominant. There are no certain proofs of the occurrence of peptide pools in the oocytes of Pomatoschistus minutus.

scholarly journals THE AMINO ACID COMPOSITION OF HYPERTENSIN II AND ITS BIOCHEMICAL RELATIONSHIP TO HYPERTENSIN I

1956 ◽  
Vol 104 (2) ◽  
pp. 183-191 ◽  
Author(s):  
Kenneth E. Lentz ◽  
Leonard T. Skeggs ◽  
Kenneth R. Woods ◽  
Joseph R. Kahn ◽  
Norman P. Shumway
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Ion Exchange ◽  
Amino Acid Composition ◽  
Acid Content ◽  
Amino Acid Content ◽  
Converting Enzyme ◽  
Terminal Sequence ◽  
Carboxyl Terminal ◽  
Hydrolysis Of

Preparations of hypertensin II, obtained from the treatment of hypertensin I by the action of the hypertensin converting enzyme of plasma and purified by countercurrent distribution, were quantitatively analyzed for their amino acid content. Chromatography on ion exchange columns showed the presence of equimolar amounts of aspartic acid, proline, valine, isoleucine, tyrosine, phenylalanine, histidine, and arginine. Hypertensin I was found to contain one mole of leucine and one mole of histidine in addition to the amino acids of hypertensin II. These two amino acids were isolated from the conversion products of hypertensin I and identified as the peptide histidylleucine. Carboxypeptidase digestion of hypertensin I showed the carboxyl terminal sequence of amino acids to be residue-phenylalanyl-histidylleucine. Similar studies of hypertensin II demonstrated residue-phenylalanine. It was concluded that the conversion of hypertensin I by the plasma hypertensin converting enzyme involved hydrolysis of the phenylalanyl-histidine bond to form hypertensin II and histidylleucine. The further removal by carboxypeptidase of phenylalanine from hypertensin II destroyed all of the vasoconstrictor activity.

scholarly journals COMPARISON OF AMINO ACIDS IN 8 DIFFERENT BOILED TROPICAL FRUITS

2019 ◽  
pp. 21-23
Author(s):  
Radha Palaniswamy ◽  
Dhanyasri Selvaraj ◽  
Sandhiya Renganathan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Content ◽  
Protein Quality ◽  
Amino Acid Content ◽  
Essential Amino Acids ◽  
Tropical Fruits ◽  
Good Balance

Objective: To determine the protein quality, especially the amino acid content of 8 tropical fruits both raw and boiled samples. Eight different tropical fruits were used in the study (Apricot, Jamun, Dragonfruit, Pomegranate, Mangustan, Litchi, Jackfruit, and Kiwi.Methods: Ninhydrin method was used for the estimation of the concentration of amino acids present in the above fruits. Raw and boiled fruits were used for the study.Results: Both raw and boiled forms which showed thats Jamun and Mangustan contained highest concentration amino acids whereas apricot shows the lowest concentration of amino acids except in Jamun which showed higher values in the raw fruit whereas in others the boiled samples showed higher values.Conclusion: It was evident that tropical fruits have a good balance of the essential amino acids (both raw and boiled fomr) which provide significant sources of protein in our diet.

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