scholarly journals Presence of Unabsorbed Free Amino Acids at the End of the Small Intestine of Humans and Pigs: Potential Implications for Amino Acid Bioavailability

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 530-530
Author(s):  
Nikkie van der Wielen ◽  
Sonja de Vries ◽  
Walter Gerrits ◽  
Kim Jannink ◽  
Paul Moughan ◽  
...  
Keyword(s):  
Small Intestine ◽  
Amino Acid ◽  
Protein Quality ◽  
Free Form ◽  
Ileal Digestibility ◽  
Funding Sources ◽  
Single Meal ◽  
The Impact ◽  
Sizable Fraction

Abstract Objectives The protein quality digestible indispensable amino acid scores (DIAAS) require determination of amino acid (AA) bioavailability, which is often quantified as the net disappearance of dietary AAs at the end of the small intestine, so-called true ileal digestibility. It is often assumed that bioavailability is mainly influenced by protein breakdown and that free AAs are completely absorbed by the small intestine. However, some studies report substantial amounts of free AAs in the unabsorbed protein fraction present in terminal ileal digesta. This study quantified free AAs in ileal digesta of humans and pigs and estimated their impact on AA bioavailability. Methods Two studies were performed with 3 diets, i.e., zein, whey or protein-free. In study 1, ileal digesta of 8 human ileostomates was collected over 9 hours after ingestion of a single meal. In study 2, 12 pigs were fed 7 days with one of the 3 diets and ileal digesta was collected over 9 h on the last 2 days according to a standardized digestibility protocol. Total and free AA content were analyzed in ileal digesta. Results All ileal digesta contained free AAs. If the analyzed free AAs would have been absorbed in the small intestine the bioavailability for whey, which was > 95%,  would only increase 0.4%-unit on average for the different AAs in humans and 0.1%-unit in pigs. For zein protein, which is ∼70% bioavailable, the impact of unabsorbed free AAs on bioavailability was on average 2.3 ± 1.2%-unit in humans and 3.5 ± 5.1%-unit in pigs. In both species, the biggest impact was seen for the free essential AA threonine; its potential absorption could increase threonine bioavailability of zein by 6.6 ± 4.0%-units for humans and  6.6 ± 8.6%-units for pigs. Moreover, for both species the proportion of threonine in free form, relative to total threonine, was significantly higher in ileal digesta after ingestion of zein compared to whey or the protein-free condition (p < 0.05). Conclusions Our results show that not all free AAs are fully absorbed by the end of the small intestine. When the AA bioavailability of a protein is low, these unabsorbed AAs can be a quantitatively sizable fraction of ingested AAs. Funding Sources Proteos project, funded by a consortium of food companies and food sectors, coordinated by Global Dairy Platform, USA.

scholarly journals Amino acid digestibility and poultry feed formulation: expression, limitations and application

2010 ◽  
Vol 39 (suppl spe) ◽  
pp. 279-287 ◽  
Author(s):  
Wayne L. Bryden ◽  
Xiuhua Li
Keyword(s):  
Amino Acid ◽  
Protein Quality ◽  
Poultry Feed ◽  
Data Set ◽  
Ileal Digestibility ◽  
Feed Formulation ◽  
Amino Acid Availability ◽  
Sources Of Variation

The nutritional value or quality of dietary proteins used for poultry feed formulation varies: amino acid availability is an important measure of protein quality. Determination of ileal digestibility values has become the preferred method for estimating amino acid availability. This review discusses the different approaches to the expression of digestibility results, including correction for endogenous loss and the derivatisation of standardised values. Sources of variation in values include, the assay protocol, anti-nutritional factors in feedstuffs and feed milling. Feed formulating with ileal digestibility values should allow higher dietary inclusion levels of protein feedstuffs of lower quality provided that values of different feedstuffs are additive, the age of the bird and the use of feed enzymes are considered. An Australian data set of "ileal digestible amino acid values in feedstuffs for poultry" that has recently be published is described. This overview is intended to stimulate interest in the generation and application of ileal digestibility as a method for estimating amino acid availability in poultry nutrition.

scholarly journals Determination of Dietary Amino Acid Digestibility in Humans

2019 ◽  
Vol 149 (12) ◽  
pp. 2101-2109 ◽  
Author(s):  
Paul J Moughan ◽  
Robert R Wolfe
Keyword(s):  
Amino Acid ◽  
Quality Evaluation ◽  
Protein Quality ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Ileal Digestibility ◽  
Growing Pig ◽  
Adult Humans ◽  
Dietary Amino Acid

ABSTRACT Dietary amino acid digestibility is a fundamental measure of importance in protein quality evaluation. Determining amino acid digestibility in humans, as the disappearance of an amino acid across the total digestive tract, has been discredited. Extensive cecal and colonic microbial metabolism renders fecal estimates of amino acids misleading. True ileal amino acid digestibility determined at the end of the small intestine predicts amino acid uptake more accurately. Given that ileal digestibility determination cannot be undertaken routinely in humans, a pig-based assay has been developed and validated. The growing pig values for digestibility, however, relate to healthy adult humans and there is a need to be able to determine amino acid digestibility for humans with specific physiological states. To this end, isotope-based methods for determining dietary amino acid digestibility indirectly show promise but remain to be fully validated.

scholarly journals Digestible Indispensable Amino Acid Score (DIAAS) better Estimates the Protein Value of Pistachios than Digestibility Corrected Amino Acid Score (PDCAAS)

2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Hannah Marie Bailey ◽  
Arianna Carughi ◽  
Hans-Henrik Stein
Keyword(s):  
Amino Acid ◽  
Unsaturated Fatty Acids ◽  
Protein Quality ◽  
Protein Digestibility ◽  
Growing Pigs ◽  
Ileal Digestibility ◽  
Indispensable Amino Acid ◽  
Older Adolescents ◽  
Adolescents And Adults ◽  
Amino Acid Score

AbstractPistachios (Pistacia Vera) are nutrient-dense foods with a healthy nutritional profile that contains fiber, unsaturated fatty acids, essential nutrients, phytochemicals and protein. However, the nutritional quality of the protein has not been characterized to date. Therefore, the objective of this study was to determine the Protein Digestibility Corrected Amino Acid Score (PDCAAS) and Digestible Indispensable Amino Acid Score (DIAAS) for raw and roasted American pistachio nuts in growing pigs. The values for apparent ileal digestibility (AID) of crude protein (CP) and the standard ileal digestibility (SID) where calculated for these proteins. The CP content was greater for raw pistachios (27.1%) compared with roasted pistachios (25.1%). The amino acid (AA) in greatest concentrations for both types of pistachio were arginine followed by leucine. The AA in the lowest concentration were tryptophan followed by methionine. The AID of CP was greater (P < 0.05) for raw pistachios than for roasted pistachios, and the AID of most indispensable AA (IAA), except arginine, isoleucine, and phenylalanine, was greater (P < 0.05) for raw pistachios. The SID of CP was greater (P < 0.05) for raw than for roasted pistachios, and the SID of all IAA, except phenylalanine, was greater (P < 0.05) for raw than for roasted pistachios. The PDCAAS value calculated for both types of pistachios was based on the requirement for children from 2 to 5 years old (FAO, 1991), whereas the DIAAS value was calculated based on the requirement for children 3 years and older, adolescents, and adults (FAO, 2013). Both raw and roasted pistachios had a PDCAAS value of 75. In contrast, the DIAAS was numerically greater for raw pistachios than for roasted pistachios with values of 86 and 83, respectively. For PDCAAS, the first limiting AA in both raw and roasted pistachios when compared with the AA requirements for children 2 to 5 years was threonine. For DIAAS, lysine was the first limiting AA in both raw and roasted pistachios when compared with the AA requirements for children 3 years and older, adolescents, and adults. Based on the DIAAS cut-off values describing protein quality (FAO, 2013), raw pistachios and roasted pistachios can both be considered a ‘Good’ quality protein if consumed by children older than 3 year, adolescents, and adults.

Most meat products have digestible indispensable amino acid scores that are greater than 100, but processing may increase or reduce protein quality

2020 ◽  
Vol 124 (1) ◽  
pp. 14-22 ◽  
Author(s):  
Hannah M. Bailey ◽  
John K. Mathai ◽  
Eric P. Berg ◽  
Hans H. Stein
Keyword(s):  
Amino Acid ◽  
Protein Quality ◽  
Meat Products ◽  
Ground Beef ◽  
Older Children ◽  
Ileal Digestibility ◽  
Indispensable Amino Acid ◽  
High Quality Protein ◽  
Adolescents And Adults ◽  
Beef Jerky

AbstractAn experiment was conducted to test the hypothesis that meat products have digestible indispensable amino acid scores (DIAAS) >100 and that various processing methods will increase standardised ileal digestibility (SID) of amino acids (AA) and DIAAS. Nine ileal-cannulated gilts were randomly allotted to a 9 × 8 Youden square design with nine diets and eight 7-d periods. Values for SID of AA and DIAAS for two reference patterns were calculated for salami, bologna, beef jerky, raw ground beef, cooked ground beef and ribeye roast heated to 56, 64 or 72°C. The SID of most AA was not different among salami, bologna, beef jerky and cooked ground beef, but was less (P < 0·05) than the values for raw ground beef. The SID of AA for 56°C ribeye roast was not different from the values for raw ground beef and 72°C ribeye roast, but greater (P < 0·05) than those for 64°C ribeye roast. For older children, adolescents and adults, the DIAAS for all proteins, except cooked ground beef, were >100 and bologna and 64°C ribeye roast had the greatest (P < 0·05) DIAAS. The limiting AA for this age group were sulphur AA (beef jerky), leucine (bologna, raw ground beef and cooked ground beef) and valine (salami and the three ribeye roasts). In conclusion, meat products generally provide high-quality protein with DIAAS >100 regardless of processing. However, overcooking meat may reduce AA digestibility and DIAAS.

scholarly journals Protein quality in experimental diets and amino acid digestibility

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 28-29
Author(s):  
Chan Sol Park ◽  
Olayiwola Adeola
Keyword(s):  
Amino Acid ◽  
Dietary Protein ◽  
Protein Quality ◽  
Sole Source ◽  
Growing Pigs ◽  
Ileal Digestibility ◽  
Distillers Dried Grains ◽  
Low Protein ◽  
Dietary Casein ◽  
Dietary Treatments

Abstract Digestibility of AA in feed ingredients for pigs has been generally determined by feeding semipurified diets containing test ingredients as a sole source of nitrogen. However, malnutrition caused by feeding semi-purified diets may affect the digestibility of AA. Therefore, the hypothesis of this study was that the standardized ileal digestibility (SID) of AA in distillers’ dried grains with solubles (DDGS) are not affected by the addition of casein in experimental diets. In Exp. 1, 20 growing pigs were allotted to dietary treatments including 2 diets containing either 480 g/kg DDGS or 308 g/kg DDGS and 60 g/kg casein. The SID of Lys and Phe for DDGS in the diet containing casein were greater (P < 0.05) than those without casein. Exp. 2 was conducted with 20 growing pigs assigned to dietary treatments containing 0, 55, 110, or 165 g/kg casein while the concentration of DDGS decreased at 466.8, 311.2, 155.6, or 0 g/kg. The SID of most indispensable AA in DDGS linearly (P < 0.05) decreased with increasing concentration of casein. Experiment 3 was conducted to verify that the results of Exp. 1 were affected by the addition of casein or by the concentration of DDGS or both. Twenty growing pigs were assigned to dietary treatments prepared as a 2 × 2 factorial arrangement with the concentration of DDGS at 466.8 or 155.6 g/kg and casein at 0 or 110 g/kg. The SID of most indispensable AA in DDGS at 466.8 g/kg were greater (P < 0.01) than in DDGS at 155.6 g/kg regardless of dietary casein. Overall, the addition of 60 g/kg casein to experimental diets may increase the SID of AA in low-protein quality ingredients but the addition of higher concentration of casein and low concentration of dietary protein from test ingredients may decrease the SID of AA.

EVALUATION OF PROTEIN IN FOODS: III. A STUDY OF BACTERIOLOGICAL METHODS

1959 ◽  
Vol 37 (11) ◽  
pp. 1351-1360 ◽  
Author(s):  
C. G. Rogers ◽  
J. M. McLaughlan ◽  
D. G. Chapman
Keyword(s):  
Amino Acid ◽  
Protein Quality ◽  
Animal Origin ◽  
Rat Growth ◽  
Amino Acid Requirements ◽  
Growth Assay ◽  
Assay Methods ◽  
Limiting Amino Acid ◽  
Egg Powder

Bacteriological methods for the determination of protein quality were evaluated by comparison with protein efficiency ratio (P.E.R.) values determined by a standardized rat growth assay. Enzyme or acid hydrolyzates of foods were used as the source of amino acids with hydrolyzed whole egg powder as the reference standard. With Streptococcus faecalis A.T.C.C. 9790 autolysis occurred in media containing hydrolyzates of proteins deficient in lysine, and was largely responsible for results which did not agree with P.E.R. values. In methods employing Leuconostoc mesenteroides P-60 A.T.C.C. 8042, growth was influenced only by the most limiting amino acid relative to the requirements of the test organism.Results with enzyme hydrolyzates correlated poorly with P.E.R. values, whereas, with acid hydrolyzates, a good correlation was obtained for cereal proteins. A difference in amino acid requirements was largely responsible for the lack of agreement between the P.E.R. assay and methods employing L. mesenteroides, particularly for legumes and foods of animal origin. It was concluded that bacteriological assay methods which have been proposed for protein evaluation are unsatisfactory as screening procedures for the evaluation of protein in foods.

scholarly journals Quantitative Analysis of Branched-chain Amino Acids in Five Nutritional Supplements Using a Leucine Dehydrogenase Assay (P23-004-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Brendan Eley
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Nutritional Supplements ◽  
Sport Nutrition ◽  
Free Form ◽  
Leucine Dehydrogenase ◽  
Funding Sources ◽  
Branched Chain Amino Acid ◽  
Branched Chain ◽  
The Given

Abstract Objectives The objective of this experiment was to determine the branched-chain amino acid (BCAA) content in five different sport nutrition supplements compared to the amount claimed on the label. Methods To measure the BCAA content of five nutritional supplements, a leucine dehydrogenase enzyme assay was used. This enzyme catalyzes the reaction of turning the given BCAA (L-leucine, L-valine, and L-isoleucine), water, and NAD+ into their respective metabolite, NH3, NADH, and H+. Ultraviolet-visible light spectrophotometry (UV/Vis) was used at 340 nm to create a standard curve. This curve uses the Beer-Lambert Law to measure NADH concentration from absorbance. NADH is in a 1:1 ratio with each BCAA molecule thus relaying the content of the given sample. The assay is specific to the three BCAAs in their free form. Other amino acids, as well as BCAAs in oligopeptides, do not interfere with this experiment. Products including oligo- and polypeptides were not included for testing. The assay was performed for each product and ran against a known standard (≥98% L-leucine) for validation. Due to different supplements having different BCAA amounts per serving, % content of the claimed amount was measured. Results Compared to the amount provided by the labels of each supplement, BCAA content was on average only 61% of the manufacturer claims when compared to ≥98% L-leucine. This shows that these BCAA supplements do not meet label claims for BCAA content (P < 0.01). Conclusions The five tested nutritional supplements contain significantly less branched-chain amino acid content than claimed on the label. This experiment can be expanded on in the future to test content of other BCAA containing supplements to determine how common underdosing is in the industry as a whole. Funding Sources The author claims no funding sources.

scholarly journals Digestible indispensable amino acid score and digestible amino acids in eight cereal grains

2014 ◽  
Vol 111 (9) ◽  
pp. 1663-1672 ◽  
Author(s):  
Sarah K. Cervantes-Pahm ◽  
Yanhong Liu ◽  
Hans H. Stein
Keyword(s):  
Amino Acid ◽  
Protein Quality ◽  
Growing Pigs ◽  
The Other ◽  
Cereal Grains ◽  
Ileal Digestibility ◽  
Indispensable Amino Acid ◽  
Dietary Requirements ◽  
Amino Acid Score ◽  
Digestible Amino Acids

To determine values for the digestible indispensable amino acid score (DIAAS), it is recommended that ileal amino acid (AA) digestibility values obtained in growing pigs are used to characterise protein quality in different foods. Therefore, an experiment was conducted to determine the standardised ileal digestibility (SID) of AA in eight cereal grains (yellow dent maize, Nutridense maize, dehulled barley, dehulled oats, polished white rice, rye, sorghum and wheat) fed to pigs, where SID values in pigs can be used to calculate approximate DIAAS values in humans. In the present experiment, twenty-four barrows with a T-cannula inserted in the distal ileum were allotted to eight diets and fed for three periods to give a total of nine replicate pigs per diet. Each period lasted 14 d, and ileal digesta samples were collected on days 13 and 14. Among the SID values obtained for all cereal grains, values for total indispensable AA were greatest (P< 0·05) in rice and lowest (P< 0·05) in rye and sorghum. The concentrations of SID indispensable AA in rice were less (P< 0·05) than in dehulled oats, but greater (P< 0·05) than in the other cereal grains, and the concentrations of SID indispensable AA in Nutridense maize were greater (P< 0·05) than in yellow dent maize and sorghum, but less (P< 0·05) than in the other cereal grains, except rye. In conclusion, results indicate that to meet dietary requirements for AA in humans, diets based on yellow dent maize or sorghum require more AA supplementation than diets based on other cereal grains.

scholarly journals Comparison of actual and predicted amino acid contents in the duodenal digesta of dairy cows

2010 ◽  
Vol 58 (5) ◽  
pp. 313-320
Author(s):  
Michal Richter ◽  
Jiří Třináctý ◽  
Ludmila Křížová
Keyword(s):  
Small Intestine ◽  
Amino Acid ◽  
Dairy Cows ◽  
Prediction Error ◽  
Prediction Accuracy ◽  
Microbial Protein ◽  
Feed Protein ◽  
Amino Acid Contents ◽  
Mean Prediction Error

In this experiment on three dairy cows with the ruminal and duodenal T-cannulas, the actual and predicted amino acid (AA) profiles of the protein fraction flowed to the small intestine were compared. The prediction was calculated by two methods: with the use of mean published AA profile of microbial protein and of experimentally determined one. The actual AA profile of digesta protein was corrected for glycine (Gly) of bile origin. In comparison to the published AA profile of microbial protein the use of the actual one did not contribute to an improvement of prediction accuracy (mean prediction error: 7.36 vs. 7.54 %, respectively). Inaccurate determination of AA composition of undegraded feed protein and the insufficient correction for Gly of bile origin were the probable sources of the residual variability.

scholarly journals 16 Sulfur amino acid utilization during immune system stimulation in growing pigs

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 15-16
Author(s):  
Anoosh Rakhshandeh
Keyword(s):  
Immune Response ◽  
Immune System ◽  
Amino Acid ◽  
Acute Phase Proteins ◽  
Growing Pigs ◽  
Synthesis Rate ◽  
Ileal Digestibility ◽  
Maintenance Requirement ◽  
Elevated Rate ◽  
The Impact

Abstract Immune system stimulation (ISS) modifies protein and amino acid (AA) metabolism in animals and humans. During ISS, AA are redirected away from growth and reproduction towards mounting an immune response. This redirection can impact AA requirements both qualitatively (i.e., the AA ratio) and quantitatively. Special attention has been given to sulfur-containing amino acid (SAA; Met + Cys) metabolism during ISS, due to their roles as precursors for the synthesis of proteins and metabolites that are involved in the immune response. A series of studies were conducted to investigate the impact of ISS on various aspects of SAA utilization, including ileal digestibility, plasma kinetics, the glutathione (GSH) synthesis rate, the irreversible loss of Cys, and dietary total SAA requirements. In all of the studies, pigs were feed restricted (≥ 2 times the maintenance requirement for ME) to eliminate the confounding effect of ISS on feed intake. Results indicated that ISS alters SAA metabolism and increases SAA requirements per unit of protein deposition. The latter occurs due to increased maintenance requirements for SAA during ISS. The results also showed that the enhanced maintenance requirement for SAA occurs mainly as a result of increased SAA utilization, mainly Cys, for the synthesis of immune system metabolites, such as GSH and acute-phase proteins, as well as the increased catabolism of Cys to taurine. In addition, we found that ISS increases the dietary Met-to-total SAA ratio in pigs, suggesting an enhanced preferential demand for dietary Met during ISS, perhaps to support an elevated rate of transsulfuration. Collectively, our findings point toward a need for developing an optimal dietary AA profile for diseased pigs.

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