Quantitative Methods for Amino Acid Analysis in Biological Fluids

Walker, Valerie; Mills, Graham A.

doi:10.1177/000456329503200103

Cited by 69 publications

(37 citation statements)

References 150 publications

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“…with a 30,000-MW cutoff, in the presence of a gas buffer (95% O 2 , 5% CO 2 ) to stabilize pH. Free Trp, Total Trp and the BCAA (leucine, isoleucine, valine) were analyzed using high-performance liquid chromatography similar to methods previously reported (Walker and Mills 1995) …”

Section: Blood Analysesmentioning

confidence: 99%

Effect of n-3 fatty acids on free tryptophan and exercise fatigue

et al. 2004

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Free tryptophan (Trp), which is augmented by liberated free fatty acids (FFA) from adipose tissue, can induce mental fatigue via serotonin during exercise. Since an attenuation in FFA has been observed with omega-3 fatty acid (n-3fa) use, our purpose was to examine the effect of n-3fa supplementation on free Trp availability and exercise fatigue. Ten recreationally trained men ( n=5) and women ( n=5), with maximal oxygen consumption (VO(2max))of 51.6 (3.0) and 44.3 (1.4) ml kg(-1) min(-1), respectively, were studied on two occasions following an overnight fast, before and after n-3fa supplementation (4 g day(-1) for 4 weeks). The exercise trials consisted of a 75-min treadmill run at 60% VO(2max) followed immediately by a high-intensity incremental bout to fatigue. Measurements included exercise monitors, plasma volume (PV), triglycerides (TG), FFA, glycerol, lactate, and glucose. Free Trp and branched-chain amino acids (BCAA) were measured and correlated with time to fatigue; all blood variables were corrected for PV. Free Trp, lactate, glucose, FFA, and glycerol were not significantly different between trials, but TG ( P<0.001) and the free Trp/BCAA ratio were significantly lower after n-3fa use [1.76 (0.18)x10(-2) microg ml(-1)] versus before supplementation [2.17 (0.22), P=0.033]. There was a non-significant increase in time to fatigue after supplementation [10.2 (0.3) min] versus before n-3fa use [9.7 (0.2), P=0.068], and a tendency for higher BCAA levels after supplementation, P=0.068. However, neither free Trp nor the free Trp/BCAA ratio significantly predicted time to fatigue. In conclusion, n-3fa supplementation did not diminish free Trp concentrations or significantly improve endurance performance during a maximal bout of exercise.

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Section: Blood Analysesmentioning

confidence: 99%

Effect of n-3 fatty acids on free tryptophan and exercise fatigue

et al. 2004

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“…Amino acid (AA) analysis in biological fluids is an important laboratory test in the diagnosis of inherited disorders of AA metabolism, the monitoring of bone and muscle disorders and of patients requiring long-term nutritional support, evaluation of new baby milks and parenteral and enteral feeds, and detection of renal drug toxicity (for a review, see Walker and Mills 1995 ). In psychopharmacological research and practice, the monitoring of tryptophan, and other aromatic and branched-chain AA (BCAA) under basal conditions and following the acute tryptophan depletion (or loading) test (Young et al 1985 ; Reilly et al 1997 ) is a vital research and diagnostic tool for assessing the role of the brain indolylamine 5-hydroxytryptamine (5-HT or serotonin) in mood and other behavioural disorders.…”

Section: Introductionmentioning

confidence: 99%

“…In psychopharmacological research and practice, the monitoring of tryptophan, and other aromatic and branched-chain AA (BCAA) under basal conditions and following the acute tryptophan depletion (or loading) test (Young et al 1985 ; Reilly et al 1997 ) is a vital research and diagnostic tool for assessing the role of the brain indolylamine 5-hydroxytryptamine (5-HT or serotonin) in mood and other behavioural disorders. Walker and Mills ( 1995 ) examined many of the problems encountered with the various AA analytical procedures. One such problem is the relatively long time required for sample preparation and analysis.…”

Section: Introductionmentioning

confidence: 99%

Application of the Phenomenex EZ:faast™ amino acid analysis kit for rapid gas-chromatographic determination of concentrations of plasma tryptophan and its brain uptake competitors

2007

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The Phenomenex EZ:faast TM amino acid analysis kit is available for gas (GC) or liquid (LC) chromatographic analysis of amino acids (AA) using mass spectrometry (MS) and other GC detectors. We used it for rapid GC determination of plasma tryptophan, its brain uptake competitors (Val, Leu, Ile, Phe and Tyr) and many other amino acids. Based on solid-phase extraction, this fast method enables one person to process two plasma samples in 8-10 min and six samples in *15 min up to GC injection and a 7-min GC run per plasma sample. Using a PerkinElmer Clarus 500 GC, a Total Chrome software, a flameionisation detector (FID) and norvaline as internal standard, we used this method to analyse *1,000 plasma samples from normal subjects undergoing acute tryptophan depletion and loading tests. The limit of detection for most amino acids is 1 nmol/ml (1 lM) and in many cases less. With manual injection, coefficients of variation for the above six amino acids were 1.5-6.2% (intra-assay) and 3.8-9.7% (interassay). This simple, rapid and elegant method will be valuable to the amino acid analyst and researcher, as it can save much manpower time and meet urgent emergency requests and the demands of a high-throughput laboratory.

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“…PUFAs have potential in reducing coronary heart disease, atherosclerosis, cancer, arthritis, hypertension and Alzheimer 3,8,14,22,25,29,30 . The percentage decrease in fat content after 1, 10 and 20 hours of exposure are 2.72, 5.51 and 7.79 respectively.…”

Section: Resultsmentioning

confidence: 99%

A Study of Ultra-Violet Irradiation on Epithelial Tissue of Fresh Water Fish, “Puntiussophore”

Sharma¹,

Srivastava²

2016

Orient. J. Chem

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The small indigenous fishes (SIFs) are known to be micronutrient rich. The gene Puntius comprises of about 134 beautiful species, out of which Puntius Sophore is an important species. Comprehensive nutrient profile of Puntius Sophore showed that it is rich in protein and minerals. In the present study we are investigating the effect of UV irradiation on epithelial tissue of fish, Puntius Sophore. The quantities of various mineral constituents, fat and amino acids were analyzed at different time intervals. This study was undertaken to evaluate the mineral and organic chemical constituents present in scale of fish, Puntius Sophore. The minerals (Na, Ca, Mg, P, and F), CO 2 and organic constituents (fat, protein and nitrogen) were determined before and after the time intervals of 1 hour, 10 hours and 20 hours of U.V. irradiation. All mineral constituents remain unchanged after U.V. irradiation. Total nitrogen, crude fat and crude protein showed continuous decrease with increase in the time of exposure. Percentage decrease in total nitrogen, crude fat and crude protein after 20 hour exposure was 2.784, 7.79 & 2.88 respectively. Likewise Amino acids content in fish scale decreases, maximum being in case of valine after 20 hours exposure. The reason for this decrease is the C-C bond cleavage with the formation of free radicals and evolution of ammonia. Exposure also reduced the weight of the scale powder.

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Quantitative Methods for Amino Acid Analysis in Biological Fluids

Cited by 69 publications

References 150 publications

Effect of n-3 fatty acids on free tryptophan and exercise fatigue

Effect of n-3 fatty acids on free tryptophan and exercise fatigue

Application of the Phenomenex EZ:faast™ amino acid analysis kit for rapid gas-chromatographic determination of concentrations of plasma tryptophan and its brain uptake competitors

A Study of Ultra-Violet Irradiation on Epithelial Tissue of Fresh Water Fish, “Puntiussophore”

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