Amino Acid Profiles, Total Nitrogen Contents, and Computed-Protein Efficiency Ratios of Manihot esculenta Root and Dioscorea rotundata Tuber Peels

Tuberous roots of cassava and yam are major sources of dietary carbohydrate to human, alternative sources of energy in livestock feeds, and sources of starch in small-scale industries. Investigations on amino acid profiles, total nitrogen contents, and computed-protein efficiency ratios (C-PER) of tuberous root peels of Manihot esculenta Crantz and Dioscorea rotundata Poir. were carried out. Amino acid analysis was carried out using ion-exchange chromatography methods. Total nitrogen content was measured using the micro-Kjeldahl methods. The C-PER was calculated using regression equation. The concentrations of amino acids detected in the cassava peels ranged from 0.54 to 6.54 g/100 g protein, whereas those of yam peels were between 0.37 and 6.25 g/100 g protein. The total amino acid concentration of the cassava peels was not significantly (p>0.05) higher than that of the yam peels. Essential amino acid scores showed that Phe + Tyr and Met + Cys were the most abundant and limiting amino acids, respectively, in cassava and yam peels. The percentage nitrogen content and C-PER of the cassava peels were significantly (p<0.05) higher than those of the yam peels. The cassava and yam peels were not sources of good quality proteins. Therefore, the use of cassava or yam peels as livestock feeds should be supplemented with other sources rich in good quality proteins.

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Changes in Amino Acid Profiles and Bioactive Compounds of Thai Silk Cocoons as Affected by Water Extraction

Molecules ◽

10.3390/molecules26072033 ◽

2021 ◽

Vol 26 (7) ◽

pp. 2033

Author(s):

Chuleeporn Bungthong ◽

Sirithon Siriamornpun

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Silk Protein ◽

Extraction Time ◽

Antioxidant Power ◽

Silk Cocoon ◽

Amino Acid Profiles

Silk proteins have many advantageous components including proteins and pigments. The proteins—sericin and fibroin—have been widely studied for medical applications due to their good physiochemical properties and biological activities. Various strains of cocoon display different compositions such as amino-acid profiles and levels of antioxidant activity. Therefore, the objectives of this study were to find a suitable silk protein extraction method to obtain products with chemical and biological properties suitable as functional foods in two strains of Bombyx mori silk cocoon (Nangsew strains; yellow cocoon) and Samia ricini silk cocoon (Eri strains; white cocoon) extracted by water at 100 °C for 2, 4, 6 and 8 h. The results showed that Nangsew strains extracted for 6 h contained the highest amounts of protein, amino acids, total phenolics (TPC) and total flavonoids (TFC), plus DPPH radical-scavenging activity, ABTS radical scavenging capacity, and ferric reducing antioxidant power (FRAP), anti-glycation, α-amylase and α-glucosidase inhibition. The longer extraction time produced higher concentrations of amino acids, contributing to sweet and umami tastes in both silk strains. It seemed that the bitterness decreased as the extraction time increased, resulting in improvements in the sweetness and umami of silk-protein extracts.

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Serum Amino Acid Profiles in Childhood Predict Triglyceride Level in Adulthood: A 7-Year Longitudinal Study in Girls

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2016-1053 ◽

2016 ◽

Vol 101 (5) ◽

pp. 2047-2055 ◽

Cited By ~ 11

Author(s):

Petri Wiklund ◽

Xiaobo Zhang ◽

Xiao Tan ◽

Sirkka Keinänen-Kiukaanniemi ◽

Markku Alen ◽

...

Keyword(s):

Amino Acids ◽

Longitudinal Study ◽

Amino Acid ◽

High Risk ◽

Triglyceride Level ◽

Early Adulthood ◽

Health Science ◽

Model Assessment ◽

Pubertal Growth ◽

Amino Acid Profiles

AbstractContext:Branched-chain and aromatic amino acids are associated with high risk of developing dyslipidemia and type II diabetes in adults.Objective:This study aimed to examine whether serum amino acid profiles associate with triglyceride concentrations during pubertal growth and predict hypertriglyceridemia in early adulthood.Design:This was a 7.5-year longitudinal study.Setting:The study was conducted at the Health Science Laboratory, University of Jyväskylä.Participants:A total of 396 nondiabetic Finnish girls aged 11.2 ± 0.8 years at the baseline participated in the study.Main Outcome Measures:Body composition was assessed by dual-energy x-ray absorptiometry; serum concentrations of glucose, insulin, and triglyceride by enzymatic photometric methods; and amino acids by nuclear magnetic resonance spectroscopy.Results:Serum leucine and isoleucine correlated significantly with future triglyceride, independent of baseline triglyceride level (P < .05 for all). In early adulthood (at the age of 18 years), these amino acids were significantly associated with hypertriglyceridemia, whereas fat mass and homeostasis model assessment of insulin resistance were not. Leucine was the strongest determinant discriminating subjects with hypertriglyceridemia from those with normal triglyceride level (area under the curve, 0.822; 95% confidence interval, 0.740–0.903; P = .000001).Conclusions:Serum leucine and isoleucine were associated with future serum triglyceride levels in girls during pubertal growth and predicted hypertriglyceridemia in early adulthood. Therefore, these amino acid indices may serve as biomarkers to identify individuals at high risk for developing hypertriglyceridemia and cardiovascular disease later in life. Further studies are needed to elucidate the role these amino acids play in the lipid metabolism.

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Chemical composition and nutritional quality of short-ripened rennet cheeses produced by traditional methods

Medycyna Weterynaryjna ◽

10.21521/mw.5971 ◽

2018 ◽

Vol 74 (10) ◽

pp. 5971-2018 ◽

Cited By ~ 1

Author(s):

PRZEMYSŁAW KNYSZ ◽

MICHAŁ GONDEK ◽

RENATA PYZ-ŁUKASIK ◽

MONIKA ZIOMEK ◽

ŁUKASZ DROZD ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Chemical Composition ◽

G Protein ◽

Nutritive Value ◽

Salt Content ◽

Amino Acid Content ◽

Traditional Methods ◽

Dairy Starter Cultures ◽

Limiting Amino Acids

The aim of the study was to determine the variability in the chemical composition and nutritive value parameters of smoked and unsmoked short-ripened rennet cheeses and unsmoked long-ripened rennet cheeses produced by traditional methods. The raw material for the production of short-ripened cheeses was pasteurized cows’ milk obtained from a dairy, whereas the long-ripened cheeses were manufactured from raw cows’ milk obtained from the producer’s farm. All three varieties of cheese examined were produced with commercial dairy starter cultures. The material for the study was collected in winter, directly at the producers’ retail outlets in southern and eastern Poland. The basic chemical composition was determined according to the Polish Standards, whereas the amino acid profiles of proteins from the cheeses were determined by ion-exchange chromatography. The result analysis revealed significant differences between the different varieties of cheese in terms of their water content, ranging from 32.2% to 42.1%, as well as protein content, which varied from 25.6% to 31.6%. Fat levels ranged between 22.2% and 24%, whereas total ash content amounted to 5.1-5.8%. The significantly highest salt content was found in unsmoked short-ripened cheeses. In all three cheese varieties, the total exogenous amino acid content was comparable, ranging from 46.17 g to 47.36 g/100 g protein, and that of endogenous amino acids varied from 52 g to 53 g/100 g protein. The biological value of proteins was determined by calculating to the chemical score (CS), as described by Mitchell and Block, and the essential amino acid index (EAAI), as described by Oser. A comparison of the results with the standard chicken egg white proteins showed that the limiting amino acids for all varieties of cheese were methionine and cysteine. On the other hand, a comparison with the FAO/WHO-suggested pattern of amino acid requirements (1991) for all age groups over 1 year of age showed that the limiting amino acids were methionine and cysteine in smoked and unsmoked short-ripened cheeses, and treonine in long-ripened cheeses. Considering the chemical indices, such as CS and EAAI, it may be concluded that the traditional rennet cheeses produced in southern and eastern Poland have a favourable amino acid composition of proteins and a high nutritive value..

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131 MODIFICATION OF AMINO ACID CONCENTRATIONS IN MEDIUM BY PIG EMBRYOS FROM THE ZYGOTE TO THE BLASTOCYST STAGE

Reproduction Fertility and Development ◽

10.1071/rdv17n2ab131 ◽

2005 ◽

Vol 17 (2) ◽

pp. 216

Author(s):

P. Booth ◽

T. Watson ◽

H. Leese

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Embryonic Development ◽

Amino Acid Profile ◽

Blastocyst Stage ◽

Morula Stage ◽

Amino Acid Profiles ◽

The Difference ◽

Amino Acid Concentrations

Pre-implantation embryos can produce and consume amino acids in a manner dependent upon stage of embryonic development (Partridge and Leese 1996 Reprod. Fert. Dev. 8, 945) that may also be predictive of subsequent viability (Houghton et al. 2002 Hum. Reprod. 17, 999). To examine these relationships in the pig, the appearance or depletion of 18 amino acids from a presumptive near-physiological mixture was determined by HPLC in porcine in vitro-produced embryos from the zygote to the blastocyst stage. Cumulus oocyte complexes derived from slaughterhouse prepubertal pig ovaries were matured for 40 h in modified TCM-199 before being fertilized (Day 0) with frozen thawed semen in tris-based medium. After 6 h, presumptive zygotes were denuded and cultured in groups of 20 in NCSU medium modified to contain a physiological mixture of 18 amino acids including 0.1 mM glutamine (NCSUaa). Groups of 2–10 embryos (dependent on stage) were removed on Day 0 (1 cell), Day 1 (2- and 4-cell), Day 4 (compact morula), and Day 6 (blastocyst) and placed in 4 μL NCSUaa for 24 h. After incubation, the embryos were removed and the medium analyzed by HPLC. Each stage was replicated 3–9 times. Since amino acid profiles of 2- and 4-cell embryos were not different, data were combined. Overall, arginine (1.19 ± 0.33), glutamine (0.78 ± 0.34) and threonine (0.05 ± 0.04) were significantly (P < 0.01) depleted from the medium whereas alanine (0.21 ± 0.1), glycine (0.20 ± 0.06), asparagine (0.13 ± 0.5), lysine (0.1 ± 0.03), isoleucine (0.08 ± 0.01), valine (0.05 ± 0.01), leucine (0.04 ± 0.02), phenylalanine (0.03 ± 0.01), and histidine (0.02 ± 0.04) significantly (P < 0.05) accumulated (mean of the 4 sampling timepoints; all values pmol/embryo/h ± SEM). The difference between amino acid accumulation and depletion (balance) was approximately equivalent between Day 0 and the morula stage although turnover (sum of depletion and accumulation) steadily decreased during this period from 3.1 on Day 0 to 1.35 pmol/embryo/h at the morula stage. However, at the blastocyst stage, turnover and balance increased to 6.32 and 2.42 pmol/embryo/h, respectively, i.e. net appearance occurred. Notable changes in amino acid profile during development included decreases in accumulation of asparagine, glutamate, and glycine in the medium and the depletion of glutamine over Days 0, 1, and 4, followed by reversal of these trends by Day 6. These data suggest that pig embryos can alter the accumulation and depletion rates of amino acids in a manner that is dependent on the specific amino acid and the stage of embryonic development. This work was supported by BBSRC.

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Metabolic Effects of the Use of Protein-Sparing Infusions in Postoperative Patients

Clinical Science ◽

10.1042/cs0580507 ◽

1980 ◽

Vol 58 (6) ◽

pp. 507-515 ◽

Cited By ~ 5

Author(s):

K. J. Foster ◽

K. G. M. M. Alberti ◽

C. Binder ◽

Leslie Hinks ◽

S. Karran ◽

...

Keyword(s):

Amino Acids ◽

Blood Glucose ◽

Amino Acid ◽

Total Nitrogen ◽

Insulin Infusion ◽

Ketone Bodies ◽

Treated Group ◽

Saline Infusion ◽

Nitrogen Excretion ◽

Protein Sparing

1. The mechanism of the purported protein-sparing effects of different postoperative intravenous regimens still remains controversial. We have therefore measured circulating concentrations of metabolites and hormones in blood and urine nitrogen excretion in patients receiving (a) sodium chloride solution (saline), (b) 1.5 g of glucose day−1 kg−1 body weight, (c) 1.5 g of glucose day−1 kg−1 with insulin (0.56 unit day−1 kg−1) or (d) mixed amino acids (1.5 g day−1 kg−1) after abdominal operation. 2. Compared with results for saline-treated patients, glucose infusion resulted in raised glucose and insulin concentrations and lowered ketone body and non-esterified fatty acid concentrations but did not influence protein catabolism. 3. Addition of insulin lowered blood glucose by approximately 1 mmol/l. Total nitrogen excretion during glucose/insulin infusion was significantly less than during saline infusion. 4. Infusion of amino acids, compared with saline infusion, resulted in raised blood glucose, alanine, serum insulin and plasma glucagon concentrations but lower concentrations of plasma non-esterified fatty acids and blood ketone bodies. Insulin concentrations, however, were similar in both amino acid- and glucose-treated groups. 5. Amino acid infusion increased urea and total nitrogen excretion but net nitrogen loss was only 1.9 mmol of nitrogen day−1 kg−1 compared with 12.7 mmol day−1 kg−1 in the saline-treated group and 11.0 mmol day−1 kg−1 in the glucose-treated group. 6. Glucose (and insulin) infusion appeared to inhibit gluconeogenesis, and amino acids to enhance it. The nitrogen-sparing effect of amino acids appears largely related to their mass and is apparently unrelated to changes in ketone bodies and insulin.

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Dissociation between plasma and brain amino acid profiles and short-term food intake in the rat

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1994.266.5.r1675 ◽

1994 ◽

Vol 266 (5) ◽

pp. R1675-R1686 ◽

Cited By ~ 3

Author(s):

G. H. Anderson ◽

E. T. Li ◽

S. P. Anthony ◽

L. T. Ng ◽

R. Bialik

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Food Intake ◽

Amino Acid Mixture ◽

Acid Mixture ◽

Short Term ◽

Egg Albumin ◽

Amino Acid Profiles ◽

Total Mixture ◽

Brain Amino Acid

The relationship between plasma and brain amino acids and short-term food intake after administration of albumin, or its constituent amino acids, was examined. Rats given protein (0.85 g chicken egg albumin) or an amino acid mixture patterned after egg albumin reduced their food intake during 1 h of feeding beginning 30 min after gavage. Similarly, when given separately, the essential (EAA) and nonessential amino acid (NEAA) fractions of egg albumin caused comparable decreases in food intake. As the dose increased from 0.5 to 1.5 g the duration of anorexia prolonged to 12 h. Little change occurred in plasma amino acids at 30 and 60 min after albumin at 0.85 g, although many increased by 25-50% at 60 min after 1.5 g. Marked changes in plasma occurred after gavage with the total mixture of constituent free amino acids and after either EAA or NEAA fractions. Brain amino acid concentrations were little affected by albumin and did not show consistent changes after the amino acid treatments. Thus the reductions in food intake after ingestion of albumin or of its constituent amino acids were not predicted from the resulting changes in either plasma or brain concentrations of amino acids.

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Minireview: Nutrient Sensing by G Protein-Coupled Receptors

Molecular Endocrinology ◽

10.1210/me.2013-1100 ◽

2013 ◽

Vol 27 (8) ◽

pp. 1188-1197 ◽

Cited By ~ 49

Author(s):

Eric M. Wauson ◽

Andrés Lorente-Rodríguez ◽

Melanie H. Cobb

Keyword(s):

Amino Acids ◽

Amino Acid ◽

G Protein ◽

Taste Receptor ◽

Sweet Taste ◽

Nutrient Sensing ◽

G Protein Coupled Receptors ◽

Amino Acid Availability ◽

Class C ◽

G Protein Coupled

G protein-coupled receptors (GPCRs) are membrane proteins that recognize molecules in the extracellular milieu and transmit signals inside cells to regulate their behaviors. Ligands for many GPCRs are hormones or neurotransmitters that direct coordinated, stereotyped adaptive responses. Ligands for other GPCRs provide information to cells about the extracellular environment. Such information facilitates context-specific decision making that may be cell autonomous. Among ligands that are important for cellular decisions are amino acids, required for continued protein synthesis, as metabolic starting materials and energy sources. Amino acids are detected by a number of class C GPCRs. One cluster of amino acid-sensing class C GPCRs includes umami and sweet taste receptors, GPRC6A, and the calcium-sensing receptor. We have recently found that the umami taste receptor heterodimer T1R1/T1R3 is a sensor of amino acid availability that regulates the activity of the mammalian target of rapamycin. This review focuses on an array of findings on sensing amino acids and sweet molecules outside of neurons by this cluster of class C GPCRs and some of the physiologic processes regulated by them.

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Amino acids and some other nitrogenous compounds in Calanus finmarchicus

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400000461 ◽

1963 ◽

Vol 43 (2) ◽

pp. 485-493 ◽

Cited By ~ 47

Author(s):

C. B. Cowey ◽

E. D. S. Corner

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Free Amino Acid ◽

Total Nitrogen ◽

Free Amino ◽

Sea Water ◽

Particulate Material ◽

Calanus Finmarchicus ◽

Acid Fraction ◽

Particulate Nitrogen

Amino acids, both free and combined as protein, and some other nitrogenous constituents of Calanus finmarchicus have been examined. Seventy-six per cent of the total nitrogen in C. finmarchicus was present in protein amino acids, 14% in the free amino acid fraction, 6% in trimethylamine oxide, and 1·5% in betaine. These findings are discussed in relation to previous work on nitrogenous constituents of Calanus.The free amino acid fraction of Calanus is compared with that of higher Crustacea and it is suggested that this fraction may be important in the adaptation of the animal to dilute sea water.Amino acid nitrogen made up 40% of the total nitrogen of particulate material from Clyde sea water. This finding is compared with other recent analyses of the phytoplanktonic nitrogen and total particulate nitrogen of inshore waters.

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Proline as an essential amino acid for the young pig

British Journal Of Nutrition ◽

10.1079/bjn19860072 ◽

1986 ◽

Vol 55 (3) ◽

pp. 659-668 ◽

Cited By ~ 62

Author(s):

Ronald O. Ball ◽

James L. Atkinson ◽

Henry S. Bayley

Keyword(s):

Amino Acids ◽

Amino Acid ◽

G Protein ◽

Crude Protein ◽

Protein Diet ◽

Single Amino Acid ◽

Amino Acid Supplementation ◽

Protein Nitrogen ◽

Dietary Amino Acids ◽

Arginine Concentration

1. The catabolism of L-[ l-14C]phenylalanine was used to indicate the effects of single amino acid supplementation of an inadequate protein diet (200 g crude protein (nitrogen x 6.25)/kg) on the utilization of dietary amino acids in pigs of 2.5 kg body-weight reared on an adequate protein diet (240 g crude protein/kg) containing skim milk and a mixture of free amino acids.2. The oxidation of phenylalanine was decreased by the addition of proline or arginine to the inadequate protein diet but not by the addition of threonine, methionine, lysine or a mixture of essential amino acids, indicating that proline and arginine were limiting the utilization of dietary amino acids in the inadequate protein diet.3. Dietary proline concentrations of 13.9 and 14.2 g/kg minimized phenylalanine oxidation in diets containing 200 or 260 g protein/kg. This indicates a dietary proline requirement of 14 g/kg.4. Increasing the dietary arginine concentration in a diet containing 240 g protein/kg showed that an arginine concentration of 5.1 g/kg minimized phenylalanine oxidation. However, increasing the arginine concentration in a diet containing 200 g protein/kg increased phenylalanine oxidation, suggesting an amino acid imbalance involving arginine at this lower level of protein.

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