The EZ:Faast Family of Amino Acid Analysis Kits: Application of the GC-FID Kit for Rapid Determination of Plasma Tryptophan and Other Amino Acids

2019 ◽  
pp. 119-130 ◽  
Author(s):  
Abdulla A.-B. Badawy
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Analysis ◽  
Rapid Determination ◽  
Plasma Tryptophan

scholarly journals 60 YEARS OF POMC: Lipotropin and beta-endorphin: a perspective

2016 ◽  
Vol 56 (4) ◽  
pp. T13-T25 ◽  
Author(s):  
D G Smyth
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Analysis ◽  
Structure And Function ◽  
Biologically Active ◽  
Molecular Endocrinology ◽  
And Function ◽  
The Brain ◽  
Quantitative Amino Acid Analysis

Many important fields of research had a humble origin. In the distant past, A J P Martin’s discovery that amino acids could be separated by paper chromatography and Moore and Stein’s use of columns for quantitative amino acid analysis provided the first steps towards the determination of structure in complex biologically active molecules. They opened the door to reveal the essential relationship that exists between structure and function. In molecular endocrinology, for example, striking advances have been made by chemists with their expertise in the identification of structure working with biologists who contributed valuable knowledge and experience. Advantage was gained from the convergence of different background, and it is notable that the whole is greater than the sum. In the determination of structure, it may be recalled that four of the world’s great pioneers (Archibald Martin, Rodney Porter, Fred Sanger and Vincent du Vigneaud) were acknowledged for their fundamental contributions when individually they were awarded the Nobel Prize. They foresaw that the identification of structure would prove of outstanding importance in the future. Indeed, study of the structures of β-endorphin and enkephalin and the different forms of opiate activity they engender has led to a transformation in our understanding of chemical transmission in the brain.

scholarly journals Rapid Determination of Amino Acids of Nitraria tangutorum Bobr. from the Qinghai-Tibet Plateau Using HPLC-FLD-MS/MS and a Highly Selective and Sensitive Pre-Column Derivatization Method

Molecules ◽  
2019 ◽  
Vol 24 (9) ◽  
pp. 1665 ◽  
Author(s):  
Wu Zhou ◽  
Yuwei Wang ◽  
Fang Yang ◽  
Qi Dong ◽  
Honglun Wang ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Content ◽  
Rapid Determination ◽  
Amino Acid Content ◽  
Tibet Plateau ◽  
Relative Standard ◽  
Nitraria Tangutorum ◽  
Qinghai Tibet Plateau

Amino acids are indispensable components of living organisms. The high amino acid content in Nitraria tangutorum Bobr. fruit distinguishes it from other berry plants and is of great significance to its nutritional value. Herein, using 10-ethyl-acridine-3-sulfonyl chloride as a fluorescent pre-column labeling reagent, a method for the efficient and rapid determination of amino acid content in N. tangutorum by pre-column fluorescence derivatization and on-line mass spectrometry was established and further validated. The limits of detection (signal-to-noise ratio = 3) were between 0.13 and 1.13 nmol/L, with a linear coefficient greater than 0.997 and a relative standard deviation between 1.37% and 2.64%. In addition, the method required a short analysis time, separating 19 amino acids within 20 min. Subsequently, the method was used to analyze the amino acid content of Nitraria tangutorum Bobr. from tissues retrieved from seven regions of the Qinghai-Tibet Plateau. Nitraria tangutorum Bobr. was shown to contain a large amount of amino acids, with the total content and main amino acid varying between the different tissues. This research supports the nutritional evaluation, quality control, and development and utilization of Nitraria tangutorum Bobr.

scholarly journals Taurine in Cerebrospinal Fluid in Friedreich's Ataxia

1978 ◽  
Vol 5 (1) ◽  
pp. 125-129 ◽  
Author(s):  
B. Lemieux ◽  
R. Giguere ◽  
A. Barbeau ◽  
S. Melancon ◽  
D. Shapcott
Keyword(s):  
Amino Acids ◽  
Cerebrospinal Fluid ◽  
Amino Acid ◽  
Aspartic Acid ◽  
Amino Acid Analysis ◽  
Friedreich’S Ataxia ◽  
Friedreich's Ataxia

SUMMARY:In a previous study we reported low values of taurine and aspartic acid in the CSF of patients with Friedreich's ataxia, when the results were compared to the literature. Further studies have revealed that tinforetold difficulties with the advertised methodology of sequential multi-sample amino acid analysis were responsible for low values in the determination of these two amino acids in the small volumes necessary for CSF. A corrected method is presented. With the latter method the differences disappear for CSF taurine and aspartic acid, but they remain valid for the previously reported blood and urine values in Friedreich's ataxia. GABA levels are also normal in Friedreich's ataxia CSF.

scholarly journals DETERMINATION OF CERTAIN AMINO ACIDS IN CHYMOTRYPSINOGEN, AND ITS MOLECULAR WEIGHT

1941 ◽  
Vol 25 (2) ◽  
pp. 167-176 ◽  
Author(s):  
Erwin Brand ◽  
Beatrice Kassell
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Osmotic Pressure ◽  
Amino Acid Analysis ◽  
Pressure Measurements ◽  
Sulfur Amino Acids ◽  
Sh Groups

1. A preparation of chymotrypsinogen, obtained from Dr. M. Kunitz, was analyzed for sulfur, the sulfur amino acids, tyrosine, and tryptophane. 2. The protein sulfur of chymotrypsinogen was accounted for as methionine, cysteine, and cystine. 3. A method is presented for calculating the minimum molecular weight of a protein from the distribution of the sulfur amino acids. In the case of chymotrypsinogen, the calculated minimum molecular weight was found to be the actual molecular weight. 4. The molecular weight of chymotrypsinogen is 36,700 by amino acid analysis as compared to 36,000 by osmotic pressure measurements of Kunitz and Northrop. Chymotrypsinogen contains per mol 17 atoms of sulfur, 3 residues of methionine, 4 of cysteine, 10 of half-cystine (i.e. 5 S—S linkages), 6 of tyrosine, and 10 of tryptophane. 5. The tryptophane content of chymotrypsinogen (5.51 per cent) is the highest of any protein so far on record. 6. Chymotrypsinogen contains no reactive SH groups, although it yields cysteine on hydrolysis. This may be due either to preformed but unreactive SH groups or to S—X groups. The term S—X group is used to denote the substitution of the sulfhydryl hydrogen by a constituent X; hydrolysis yields SH groups: S—X + HOH = SH + X—OH.

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.

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