Amino acid bioavailability

Lewis, A. J.; Bayley, H. S.

doi:10.1016/b978-012056250-3/50029-9

Cited by 39 publications

(24 citation statements)

References 90 publications

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“…Assays of nutrient bioavailability, which provide relative information on the capacity of a feed ingredient to supply a specific limiting nutrient and promote growth, are usually considered the ultimate standards against which other methods are judged due to the inherent feature of taking into account all of the processes of digestion, absorption and utilization of the specific limiting amino acid (Lewis and Bayley, 1995). The data from these studies suggest that the bioavailabilities of thr and trp in peanut meal, using weight gain or gain-to-feed ratio as dependent variables, are 72% to 76% and 76% to 92%, respectively.…”

Section: Discussionmentioning

confidence: 99%

“…Factors affecting this bioavailability include digestibility and utilization of the absorbed amino acids for incorporation into protein; moreover, not all the digested and absorbed amino acids are available for use in protein synthesis. Bioavailability assays based on animal performance provide relative information on the capacity of a feed ingredient to provide a specific limiting amino acid for maintenance and growth, and are usually considered as the ultimate standards against which other methods are judged (Lewis and Bayley, 1995). Commonly used variables in a slope-ratio assay are weight gains and gain : feed ratio (Adeola, 1996).…”

Section: Introductionmentioning

confidence: 99%

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Bioavailability of threonine and tryptophan in peanut meal for starter pigs using slope-ratio assay

Adeola

2009

Animal

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The objective of the two studies was to determine the bioavailability of threonine (thr) and tryptophan (trp) in peanut meal, relative to L-thr and L-trp, for starter pigs using the slope-ratio bioassay. Basal diets (BDs) contained surfeit amounts of all amino acids for 10 to 20 kg pigs, except for thr (Experiment 1) or trp (Experiment 2). In the first study, four reference diets were formulated by supplementing the BD with 0, 0.4, 0.8 or 1.2 g of L-thr/kg at the expense of cornstarch; two test diets were formulated by replacing cornstarch in the BD with peanut meal at 32 or 64 g/kg of diet to supply 0.4 or 0.8 g thr/kg, respectively. Four reference diets consisting of the BD supplemented with 0, 0.15, 0.3 or 0.45 g of L-trp/kg at the expense of cornstarch and two test diets in which cornstarch in the BD was replaced with peanut meal at 30 or 60 g/kg of diet to supply 0.14 or 0.28 g trp/kg, respectively were used in the second study. Body weight gain responded in a linear way to supplemental L-thr or thr from peanut meal ( P , 0.001). There was a linear response ( P , 0.001) to thr supplementation from L-thr or peanut meal in gain-to-feed ratio. The addition of trp to the BD linearly increased ( P , 0.05) body weight gain, feed intake and gainto-feed ratio regardless of the trp source. Common-intercept, multiple linear regression in slope-ratio methodology using weight gain or gain-to-feed ratio as dependent variables and supplemental thr intake as independent variable gave relative bioavailability estimates of 71.9% or 75.7%, respectively. Corresponding values for trp were 92% and 75.7%. The fiducial limits for none of the relative bioavailability estimates included 100%. The data from these studies suggest that the bioavailabilities of thr and trp in peanut meal are less than those of L-thr and L-trp, and that the bioavailabilities of thr and trp in peanut meal are 72% to 76% and 76% to 92%, respectively.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Bioavailability of threonine and tryptophan in peanut meal for starter pigs using slope-ratio assay

Adeola

2009

Animal

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“…In recent years much interest has focused on covering amino acid requirements of animals for growth, development and productivity (Batterham, 1992;Lewis and Bayley, 1995;Zebrowska and Buraczewska, 1998;Ravindran and Bryden, 1999). Thus, because amino acid composition is so important, physiologists, geneticists or nutritionists should be interested in developing more accurate and precise amino acid analyses.…”

Section: Introductionmentioning

confidence: 99%

Determination of free- and protein primary amino acids in biological materials by high-performance liquid chromatography and photodiode array detection

Czuderna¹,

Kowalczyk²,

Niedźwiedzka³

et al. 2002

J. Anim. Feed Sci.

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Work from this laboratory resulted in improved high-performance liquid chromatography methods for quantification of free-and protein primary amino acids in biological materials. Biological samples were hydrolyzed with 6 M HC1 for 20 h at 104±2°C. Primary amino acids, with the exception of tryptophan, were separated after pre-column derivatization with o-phthaldialdehyde (OPA) in the presence of ethanethiol (ESH). Derivatized amino acids were analyzed using a Nova Pak C 18 column (4 jum, 250 x 4.6 mm I.D., Waters) by quaternary gradient system I. Detection was carried out simultaneously using UV monitoring at 337 nm and fluorescence detection (\J^c m -336/425 nm). Derivatized amino acids were completely resolved from all interfering species in about 50 min. HPLC system I with two detection modes can also be used for quantification of free primary amino acids in ovine blood plasma. A trace amount of cysteine as its OPA/ESH derivative can be quickly quantified (~ 3.5 min) using an isocratic HPLC system with UV detection at 274 nm. Separation and quantification of tryptophan in alkaline hydrolysates was achieved without derivatization using the same HPLC column by ternate gradient elution system II with UV monitoring at 219 nm or fluorescence detection (^e x /^e m = 280/360 nm). The obtained average recoveries of assayed amino acids added to biological samples were near 100% when UV and fluorescence detection were applied. Generally, fluorescence detection in comparison with UV monitoring offers lower limits of detection (0.04-1.25 vs 0.05-12.7 jumoM" 1 ) and quantification (0.12-11.7 vs 0.18-42.0 jumol-l" 1 ), however, the sensitivity of the UV detection mode is satisfactory for accurate and precise quantification of free-and protein amino acids in biological materials. The HPLC systems with UV detection assured better resolution of amino acid peaks in comparison with fluorescence detection. Satisfactory purity of analytical amino acid peaks (near 100%) and precision of HPLC systems with both detection modes renders these procedures suitable for routine analysis of amino acid concentrations in large numbers of 144 METHODS OF AMINO ACIDS DETERMINATION biological samples. HPLC system I enabled quantification of 2,6-diaminopimelic acid, so the current chromatographic system can also be applied for the estimation of bacterial protein production in ruminants.

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“…Bioavailability is defined as the extent to which an ingested nutrient is digested and absorbed in a form that can be utilized by the animal (Batterham, 1992;Lewis and Bayley, 1995). Bioavailability of ingredients or supplemental products, such as L-lysine sulfate and L-lysine HCl, can be compared in order to understand their relative ability to supply a nutrient.…”

Section: Introductionmentioning

confidence: 99%

Assessing the bioavailability of l-lysine sulfate compared to l-lysine HCl in rainbow trout (Oncorhynchus mykiss)

Powell

Chowdhury²,

Bureau

2015

Aquaculture

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Amino acid bioavailability

Cited by 39 publications

References 90 publications

Bioavailability of threonine and tryptophan in peanut meal for starter pigs using slope-ratio assay

Bioavailability of threonine and tryptophan in peanut meal for starter pigs using slope-ratio assay

Determination of free- and protein primary amino acids in biological materials by high-performance liquid chromatography and photodiode array detection

Assessing the bioavailability of l-lysine sulfate compared to l-lysine HCl in rainbow trout (Oncorhynchus mykiss)

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