Important Essential Amino Acids Research Articles

Boerhavia diffusa and Coccinia grandis: Two indigenous vegetables as a source of essential minerals, vitamins, amino acids, and fatty acids

Since the nutritional makeup of many plants is still unknown, people have historically included them in their diets without even being aware of their health advantages. Therefore, the present study aimed to uncover the proximate composition, minerals, vitamins, amino acids, and fatty acids composition of two locally consumed vegetables, namely Boerhavia diffusa and Coccinia grandis. From the analysis, these vegetables had a significant protein, fat, and carbohydrate content. Regarding mineral contents, both plants had a great amount of potassium, calcium, iron, sodium, and zinc. These vegetables had a remarkable content of vitamins such as B1, B2, B3, B5, B6, and C. The leaves of both plants had important essential amino acids such as leucine, lysine, and phenylalanine, as well as non-essential amino acids. Unsaturated fatty acids such as linolenic acid, linoleic acid, and erucic acid were more prominent in Coccinia grandis than Boerhavia diffusa. In addition, both plants had a significant amount of saturated fatty acids such as palmitic acid, stearic acid, and lauric acid. Thus, it can be concluded that these two vegetables have magnificent profiles of nutrients which could make them as important sources of minerals, vitamins, and fatty acids.

Full nutritional spectrum and hazard risk assessment of high commodity value aquaculture species in Penang, Malaysia

Aquaculture is a rapidly growing food production sector that aims to alleviate global hunger, malnutrition, food security and nutrient deprivation. This study aimed to update the full spectrum of nutritional composition using aquaculture species. High commodity value aquaculture species in Penang, Malaysia have been shortlisted, followed by nutritional quantification and health risk estimation. Nutritional compositional analysis involved proximate analysis, and amino acid, fatty acid, vitamin, mineral and heavy metal quantification. Health risk assessment was conducted to determine whether the benefits were greater than the risks in the long term. Ten (10) aquaculture species, namely golden pomfret, golden snapper, seabass, bigeye trevally, red snapper, grouper, African catfish, blood cockles, white-leg shrimp and tiger prawn, have been studied extensively. The results showed that all species contained adequate protein and lipid contents, ranging from 13.6 % to 26.9 % and 0.4–15.8 %, respectively. The essential amino acid (EAA) to total amino acid (TAA) ratio of the culture species was comparable to the FAO reference values (50 %), with leucine and lysine demonstrating the most important EAAs. Fatty acid profiling revealed that both seabass and grouper were rich in polyunsaturated fatty acids, particularly docosahexaenoic acid. Golden pomfret and red snapper contained the greatest amounts of riboflavin and pyridoxine. The atherogenic and thrombogenic indices were within the permissible ratio (<1), except for those of African catfish. Notably, the arsenic (As) content in blood cockles exceeded the permissible criterion values. Hazard index (HI) assessment indicated that prolonged consumption of blood cockles, white-leg shrimp, tiger prawn, bigeye trevally and golden snapper demonstrated potent non-carcinogenic risk for both adults and children. This study provides an initial platform for informing consumers, stakeholders and policy makers about aquaculture nutritional benefits, consumption safety concern and health indicators.

Acrylate-guided chemoselective fluorescent detection of arginine and lysine in aqueous media

Arginine (Arg) and lysine (Lys), as two important essential amino acids, are widely used in many fields. Here, a novel fluorescent probe (R)-3 based on 1,1′-binaphthol (BINOL) was synthesized and it could chemoselectively detect Arg and Lys by complexing with zinc ions. The response time of each amino acid only need 1 min. The detection limit of the probe for D-/L-Arg were 60 nM and 123 nM, respectively, and the detection limit for Lys was 53 nM. Mechanistic studies revealed that the chemoselectivity comes from the selective 1,4-Michael addition to the acrylate group of the probe. The probe advantaged in low detection limit, high sensitivity, chemoselectivity and that the fluorescent detection proceeded in aqueous phase. A test strip for rapid detection of arginine was prepared, which gave yellowish color to Arg under natural light and bright yellow to Arg under 254 nm ultraviolet light. The test strip allows rapid detection and easy visualization for Arg.

A fast survey on recent developments in designing colorimetric and fluorescent sensors for the selective detection of essential amino acids.

Owing to the biological significance of various amino acids, developing accurate and cost-effective sensing techniques for the selective detection of amino acids has recently attracted growing interest. This review discusses the recent advancements of chemosensors in the selective detection of only essential amino acids out of a total of twenty amino acids, which have been applied in chemosensing research, and the mechanism of their action. The focus is directed towards the detection of the most important essential amino acids, like leucine, threonine, lysine, histidine, tryptophan and methionine, since isoleucine and valine are yet to be explored in regard to chemosensing. According to their chemical and fluorescence properties, different sensing techniques, such as the reaction-based approach, DNA-based sensors, nanoparticle formation, coordination ligand binding, host-guest chemistry, the fluorescence indicator displacement (FID) approach, electrochemical sensors, carbon dot-based sensors, MOF-based sensors and metal-based techniques, have been described.

The Role of Branched-Chain Amino Acids and Branched-Chain α-Keto Acid Dehydrogenase Kinase in Metabolic Disorders.

Branched-chain amino acids (BCAAs), composed of leucine, isoleucine, and valine, are important essential amino acids in human physiology. Decades of studies have revealed their roles in protein synthesis, regulating neurotransmitter synthesis, and the mechanistic target of rapamycin (mTOR). BCAAs are found to be related to many metabolic disorders, such as insulin resistance, obesity, and heart failure. Also, many diseases are related to the alteration of the BCAA catabolism enzyme branched-chain α-keto acid dehydrogenase kinase (BCKDK), including maple syrup urine disease, human autism with epilepsy, and so on. In this review, diseases and the corresponding therapies are discussed after the introduction of the catabolism and detection methods of BCAAs and BCKDK. Also, the interaction between microbiota and BCAAs is highlighted.

Dietary lysine level affects digestive enzyme, amino acid transport and hepatic intermediary metabolism in turbot (Scophthalmus maximus)

Lysine is one of the most important essential amino acids in fish, especially in the feed formulated with high levels of plant ingredients. Lysine restriction always led to growth inhibition and poor feed utilization. However, little information was available on its effects on digestion, absorption, and metabolism response in fish. In the present study, three experimental diets were formulated with three lysine levels, 1.69% (LL group), 3.32% (ML group), and 4.90% (HL group). A 10-week feeding trial was carried out to explore the effects of dietary lysine levels on the digestive enzymes, amino acid transporters, and hepatic intermediary metabolism in turbot (Scophthalmus maximus). As the results showed, the activities of lipase and trypsin in ML group were higher than in other groups. Lysine restriction inhibited the expression levels of peptides and amino acid transporters such as PpeT1, y+LAT2, b0,+AT, and rBAT but significantly induced the expression of CAT1. Meanwhile, lysine deficiency elevated the content of T-CHO and LDL-C in plasma, while a higher HDL-C/LDL-C ratio was observed in ML group. For hepatic intermediary metabolism, the increase of lysine level induced the mRNA expression of G6Pase1 and FBPase, but no differences were observed in the expression of the key regulators in glycolysis pathway, such as GK and PK. Furthermore, an appropriate increase in the level of lysine promoted the genes involved in lipolysis, including PPARα, ACOX1, CPT1A, and LPL. However, no differences were observed in the expression of PPARγ, FAS, SREBP1, and LXR, which were important genes related to lipid synthesis. These results provide clues on the metabolic responses on dietary lysine in teleost.

Improvement of acetyl-CoA supply and glucose utilization increases l-leucine production in Corynebacterium glutamicum.

l-Leucine is an important essential amino acid with multiple industrial applications, whose market requirements cannot be met because of the low productivity. In this study, a strain of Corynebacterium glutamicum with high l-leucine yield was constructed to enhance its acetyl-CoA supply and glucose utilization. One copy of leuA under the control of a strong promoter was incorporated into the C. glutamicum genome. Then, acetyl-CoA supply was increased by the integration of a terminator in front of gltA and by the heterogeneous overexpression of acetyl-CoA synthetase (ACS) and deacetylase (CobB) derived from Escherichia coli. Next, the transcriptional regulator sugR was deleted to enhance glucose uptake via a phosphotransferase-mediated route. In fed-batch fermentation performed in a 5-L reactor, l-leucine production of 40.11 ± 0.73g L-1 was achieved under the optimized conditions, with an l-leucine yield and productivity of 0.25g g-1 glucose and 0.59g L-1 h-1 , respectively. These results represent a significant improvement in the l-leucine production of C. glutamicum, indicating that the process possesses high potential for industrial application. These strategies can be also expanded to enable the production of other value-added biochemicals derived from the intermediates of central carbon metabolism.

PRODUCTION OF COMPOUND FEEDS FOR BUDGERIGARS-PROSPECTIVE DIRECTION OF COMPOUND FEED DEVELOPMENT

The article describes that budgerigar is one of the most popular domestic birds. Budgerigars have become so popular thatthey have "overtaken" even canaries in this regard.The budgerigars eat the same as other parrots. They like nuts, millet, oats and wheat. Undoubtedly, they need fruits andvegetables for development and growth. They like to indulge in slices of tangerine and lemon, pears and apples.It is advisable to use pelleted feed to meet all the needs of parrots in nutrients and biologically active substances. These aresmall dry pellets balanced in the amount of nutrients, with the addition of important essential amino acids and vitamins. Pelleted feedis made from a mixture of cereals, vegetables, mineral and vitamin supplements. No additional synthetic vitamins or supplements arerequired when feeding pelleted feed.Parrots are popular in the world. The budgerigars rank 4th in Ukraine in popularity among pets after cats and dogs.The pet feed market has existed for about 20 years in Ukraine, so in terms of volumes it lags far behind the world's leadingmarkets. At the same time, the Ukrainian pet feed market is characterized as fast-growing according to analysts at Euromonitor International.It is considered that Ukraine is in 8th place in the TOP-10 fast-growing pet feed markets. However, the Ukrainian marketis dominated by foreign producers feed from countries such as Hungary, Russia, the United States, France and others.The following brands are among the budgies feed in Ukraine: «Lori», «Nature», «Maxi», «Special One», etc.Proper feeding of budgies does not cause much trouble nowadays. Parrots like solid feed consisting of a mixture of cereals,and soft feed from fruits, vegetables and protein foods.Pellets are a solution for parrot owners who haven’t time to closely monitor their pet's diet. The pellets contain choppedfruits, vegetables and other useful components (depending on the brand and product). They can be given to the bird if it is not possibleto get fresh food.The pellets have advantages and disadvantages. The disadvantages include the difficult transition to a such diet, as theparrot does not understand that it is food. Advantages: the composition of pellets is enriched with essential and non-essential aminoacids and vitamins. Pelleted feed is well balanced for the daily diet and haven’t husks as an additional positive effect.The cost of raw materials for the developed pelleted feed is on average 10 UAH per 1 kg. It is advisable to produce pelletedfeed for budgies, because the low cost and high quality will attract owners of budgies.

Nutritional Evaluation of the Leaf Meal of &amp;lt;i&amp;gt;Gongronema latifolia&amp;lt;/i&amp;gt;

Background: The leaves of G. latifolia have long been employed in ethnomedical practices, and as food additive among the local populations in Nigeria. This study was carried out to evaluate the nutritive value of G. latifolia through the proximate, mineral and phytochemical analysis of G. latifolia leaf meal (GLLM), as well as analysis of amino acid profile of GLLM protein. Methods: Standard analytical procedures were employed for proximate, mineral and phytochemical analysis of GLLM, and amino acid analysis of GLLM protein. Results: Values obtained for proximate fractions on dry matter basis were: crude protein, 14.25%; Ether extract, 2.84%; and Ash, 6.26%. Others included Crude Fiber, 2.84%; Nitrogen free extractive, 60.39%, and Metabolizable energy, 2903.41Kcal/kg. The concentrations (mg/100g) of the five minerals investigated were Calcium, 10.80; Magnesium, 45.0; Potassium, 486.0; Sodium, 3.86, and Phosphorus, 395.0. Amino acid analysis of the leaf meal protein of the plant revealed that it contains nutritionally important essential and non-essential amino acids in concentrations that compare favorably with standard provisional requirement pattern: The total amino acids (TAA) content was 66.38g/100g protein; Total Essential amino acid (TEAA) with histidine was 32.53g/100g protein; Total Non-essential Amino acid (TNEAA) was 33.85g/100g protein; Percentage Total Essential Amino acid with Histidine was 49.01 protein; Percentage Essential Amino acid without Histidine recorded 45.71g/100g protein; Percentage Total Non-essential Amino acid was 50.99g/100g protein. The amino acid scores, vis-avis standard provisional scoring pattern were: Leucine, 95.7%; Isoleucine, 85.0%; Lysine, 72.7%; Methionine + cysteine, 48.6%; Phenylalanine + Tyrosine, 115.0%; Threonine, 75.0%; Valine, 80.0% The amino acids which were in abundance relative to others were: Glutamic acid, Aspartic acid, Leucine, Arginine, Valine, Phenylalanine, Lysine, Glycine and Isoleucine with the values of 9.27, 7.75, 6.70, 4.42, 4.09, 4.01, 3.97, 3.60 and 3.39 (g/100g protein), respectively. However, the first limiting amino acid(s) recorded in its amino acid profile were the two Sulphur-containing amino acids, methionine + cystein, the sum of which scored 48.60% in the amino acid scoring system. The phytochemical factors studied and their percentage compositions wer: alkaloids, 1.03%; flavonoids, 0.37%; saponins, 0.47% and tannins 0.55%. Other phytochemicals measured (mg/100g) included Phenols, 0.17; Phytates, 0.12, and Cyanogenic glycosides, 7.07. Conclusion: The result of this study suggests that Gongronema latifolia could contribute significant nutritional benefits to human and livestock nutritional needs. However, further research is needed to ascertain specific administration regimen of GLLM or the phyto-nutrients of G. latifolia leaf extracts.

Dietary Valine Ameliorated Gut Health and Accelerated the Development of Nonalcoholic Fatty Liver Disease of Laying Hens.

Valine is an important essential amino acid of laying hens. Dietary supplemented with BCAAs ameliorated gut microbiota, whereas elevated blood levels of BCAAs are positively associated with obesity, insulin resistance, and diabetes in both humans and rodents. General controlled nonrepressed (GCN2) kinase plays a crucial role in regulating intestinal inflammation and hepatic fatty acid homeostasis during amino acids deficiency, while GCN2 deficient results in enhanced intestinal inflammation and developed hepatic steatosis. However, how long-term dietary valine impacts gut health and the development of nonalcoholic fatty liver disease (NAFLD) remains unknown. Hence, in the present study, we elucidated the effects of dietary valine on intestinal barrier function, microbial homeostasis, and the development of NAFLD. A total of 960 healthy 33-weeks-old laying hens were randomly divided into five experimental groups and fed with valine at the following different levels in a feeding trial that lasted 8 weeks: 0.59, 0.64, 0.69, 0.74, and 0.79%, respectively. After 8 weeks of treatment, related tissues and cecal contents were obtained for further analysis. The results showed that diet supplemented with valine ameliorated gut health by improving intestinal villus morphology, enhancing intestinal barrier, decreasing cecum pathogenic bacteria abundances such as Fusobacteriota and Deferribacterota, and inhibiting inflammatory response mediated by GCN2. However, long-term intake of high levels of dietary valine (0.74 and 0.79%) accelerated the development of NAFLD of laying hens by promoting lipogenesis and inhibiting fatty acid oxidation mediated by GCN2-eIF2α-ATF4. Furthermore, NAFLD induced by high levels of dietary valine (0.74 and 0.79%) resulted in strengthening oxidative stress, ER stress, and inflammatory response. Our results revealed that high levels of valine are a key regulator of gut health and the adverse metabolic response to NAFLD and suggested reducing dietary valine as a new approach to preventing NAFLD of laying hens.

Micro determination of tyrosine by spectrophotometric techniques

The Tyrosine compound could be considered most important essential amino acid for biological activities, also extremely very important and so vital to successes for the process of neurotransmitter synthesis. The main aim of this paper was to improvement and modified procedure for ultra micro assessment of Tyrosine compound through a reaction of coupling between our target material Tyrosine and diazotized solution of Anthranilic acid in basic medium to yield a salt complex with a higher absorptivity at 455nano meter. Different parameter should be evaluated, standard calibration curve have been done to concentration range (8.09×10−7 - 1.11×101ig/mL), also the value for absorptivity of molar founded 1.7×103 L. mol−1.cm−1, beside to we found that (R.S.D.) value was less than1.12% and the value of recovery it is 99.78%. Mole ratio appeared as 1:1 (Tyrosine: Anthranilic acid). Our procedure confirmed different advantages like simplicity, not necessary providing expertize person to do this work and could be recommended for ultra micro determination of tyrosine in all field. This method could be properly validated for assessment of tyrosine in biologically samples.

Arginine supplementation in plant‐rich diets affects growth, feed utilization, body composition, blood biochemical indices and gene expressions of the target of rapamycin signaling pathway in juvenile Asian red‐tailed catfish (Hemibagrus wyckoiides)

AbstractArginine (Arg) is an important essential amino acid required for optimum fish growth. However, its role in plant‐rich diets on growth and the required level in juvenile Hemibagrus wyckioides are currently unknown. This study evaluated the effects of Arg supplementation in plant‐rich diets on growth, feed utilization, whole body composition, blood biochemical indicators and gene expressions of the target of rapamycin (TOR) signaling pathway in juvenile H. wyckioides. A total of 450 fish (6.40 ± 0.06 g) were randomized into six equal groups and fed on diets with graded Arg levels: 0 (control), 3, 6, 9, 12 and 15 g/kg of dry feed for eight weeks. The results revealed that specific growth rate (SGR) and feed conversion ratio of juvenile H. wyckioides were significantly improved and reduced, respectively in fish fed on 9 g/kg of Arg supplementation (p &lt; .05). The optimum amount of dietary Arg content in plant‐rich diets for H. wyckioides was 63.77 g/kg diet based on SGR. Feeding fish with dietary Arg supplementation ranging from 9 to 12 g/kg improved significantly (p &lt; .05) whole body protein contents and decreased lipid deposition. The mRNA levels of TOR, eukaryotic translation initiation factor 4E (4EBP) and ribosomal protein S6 kinase 1 (S6K1) in muscle and liver were significantly affected by increasing dietary Arg levels. Meanwhile, the mRNA relative expression levels of TOR and S6K1 in the liver and muscle increased significantly as Arg supplementation increased. On the other hand, the mRNA relative expression levels of 4EBP was significantly higher in fish fed on the 9 g/kg Arg diet compared to those fed on the control and 15 g/kg Arg diets. In conclusion, our current results indicate that dietary Arg supplementation in plant‐rich diets, might activate the TOR signaling pathway, which promotes protein synthesis and reduces lipid accumulation of H. wyckioides, resulting in improved growth.

Raw materials and feed production technology for valuable fish species in the Republic of Belarus

The paper raises problems of production of domestic compound feed for valuable fish species. The following representatives of valuable fish species are reared in the Republic of Belarus: rainbow trout, sterlet sturgeon, sturgeon, European and African catfish. All these types need high-quality and inexpensive compound feeds. Production of such feed is developing in our country. All the feeds for valuable fish species are extruded in the modern world. A range of raw materials has been studied that can be used as part of compound feeds for valuable fish species, such as Belarusian made fish meal, dry hemoglobin, soy concentrate, and whey fat concentrate. It has been determined that Belarusian fishmeal is of high quality and not inferior in balance to the amino acid composition of imported fishmeal made in Mauritania, and in terms of leucine and isoleucine level, over 2 times exceeds the imported one. Amino acid composition of dry hemoglobin was studied. It was determined that this feed additive can be used only for balancing feed for crude protein level and practically does not contain such an important essential amino acid as methionine. Valuable fish species are predators, for this reason compound feed contain high amount of protein (up to 50 %) and fat (up to 30 %) depending on the type and age of the fish. Therefore, soy protein concentrate can be used in terms of protein content and absence of anti-nutritional substances in compound feed, and whey-fat concentrate can be used for balancing the formulation for fat content. At the same time, the need for development of such deep processing industry in our republic is noted.

Effect of Planting Methods on the Quality of Three Egyptian Rice Varieties

Abstract In Egypt, the traditional transplanting method of rice planting is substituted by broadcasting and dibbling recently. This paper studies the effects and the changes occur in different rice varieties due to different methods on grain quality and amino acids of rice. Three Egyptian rice cultivars belonging to japonica, japonica/indica and indica subspecies were investigated for grain quality, protein and amino acid composition under three planting methods, i.e., broadcasting, seedling transplanting and dibbling. A strip plot design with three replications was used; the investigated three rice cultivars occupied the horizontal main plot, while three planting methods were devoted to the vertical main plot. The method of planting did not affect significantly the grain dimension, but it affected significantly the milling characters and the 1,000-grain weight. The highest milling characters and 1,000-grain weight came from transplanting, while the lowest one from the dibbling method. There was no significant difference between transplanting and broadcasting in milling characters and 1,000-grain weight. The chemical and cooking characters of grains showed no significant differences in moisture content and gelatinization temperature characters, while the differences in protein content and elongation were significant among the varieties and planting methods. The interaction between the planting method and rice had significant effect on the protein content. The most important essential amino acids according to the FAO/WHO pattern were not affected significantly by the different methods of planting. This means that the biological value of rice grains is not affected by different methods of planting.

Expression and characterization of a lysine rich protein in cow milk

The lysine is considered as the most important essential amino acid, because it is the most limiting in the cereals grains. In this study, a lysine-rich (LR) gene, and the expression vector pcDNA3.1-LR and pBC1-LR were constructed. The LR was expressed in 293T cells driven by the vector pcDNA3.1-LR and checked by RT-PCR and WB. The mammary gland tissue-specific expression vector carrying the LR was injected directly into the lactating mammary glands of cows and the milk samples were checked by a complete amino acid analysis. The results showed that the LR protein was expressed successfully in cells and in cow milk; the expression of LR lasted for 6 d, and the lysine level of the injection group was significantly higher than that of negative controls (p Lass Than 0.05). This study provide a better understanding of how mammary gland expression systems increase the lysine content of milk that can be applied to transgenic dairy cow.

Untapped amaranth (Amaranthus spp.) genetic diversity with potential for nutritional enhancement

Significant genetic diversity was observed in 218 out of a total of 1309 accessions of amaranth (Amaranthus hypochondriacus L.) and its seven wild relatives, A. spinosus L., A. dubius Mart. ex Thell., A. hybridus L., A. tricolor L., A. cruentus L., A. caudatus L., A. retroflexus L. for 24 nutritional parameters including total oil content, fatty acid profile, total protein content and amino acid profile. Diversity for total oil content (6.42–12.53%), linoleic acid (25.68–54.34%), oleic acid (21.97–42.01%) of the total fatty acids, total protein content (7.84–18.01%), among important essential amino acids; lysine content (0.66–11.12 g/16 g N), methionine (0.35–4.80 g/16 g N) and half cystine and (0.12–8.32 g/16 g N) was reported. The un-weighted pair-group method using arithmetic average cluster analysis based on pair wise Euclidean genetic distance grouped the accessions into seven major clusters. Histidine, half cystine, tyrosine, essential amino acids, total oil content, linoleic acid and oleic acid content were the major parameters contributing significantly to genetic diversity. Present findings indicate that significant diversity exists for nutritional parameters in amaranth germplasm. The promising accessions with higher multiple nutritive traits; protein content (>16%), oil content (>11%), lysine content (>7.5 g/16 g N) and EAA higher than the FAO reported values, were identified. This is the first report on detailed nutritional analysis of diversity collected worldwide. These could be used as potential breeding material for nutritional enhancement through genetic improvement. This will help in overcoming the “triple burden” of malnourishment, hidden hunger, and obesity.

Indoleamine 2,3-dioxygenase (IDO): Only an enzyme or a checkpoint controller?

Abstract Tryptophan (Trp) is one of the important essential amino acids and Kynurenine pathway (KP) is the first and rate limiting step of degrading Trp to active metabolites. Recent studies showed that KP metabolites have antimicrobial and immunosuppressive roles. The main controller enzyme of this pathway is indoleamine-2,3-dioxygenase (IDO). IDO is an intracellular monomeric, heme-containing enzyme that controls the Trp breakdown in the KP. In this review, we discuss IDO functions on cancer progression and prognosis, and possible therapeutic aspects of inhibition of IDO on cancer immunotherapy.

Leucine Metabolism in T Cell Activation: mTOR Signaling and Beyond

AbstractIn connection with the increasing interest in metabolic regulation of the immune response, this review discusses current advances in understanding the role of leucine and leucine metabolism in T lymphocyte (T cell) activation. T cell activation during the development of an immune response depends on metabolic reprogramming to ensure that sufficient nutrients and energy are taken up by the highly proliferating T cells. Leucine has been described as an important essential amino acid and a nutrient signal that activates complex 1 of the mammalian target of rapamycin (mTORC1), which is a critical regulator of T cell proliferation, differentiation, and function. The role of leucine in these processes is further discussed in relation to amino acid transporters, leucine-degrading enzymes, and other metabolites of leucine metabolism. A new model of T cell regulation by leucine is proposed and outlines a chain of events that leads to the activation of mTORC1 in T cells.

Low Light During Grain Filling Stage Deteriorates Rice Cooking Quality, but not Nutritional Value

To investigate the effect of low light (LL, 50% natural light) during grain filling (GF) stage on rice transamination, amino acid (AA) accumulation, nutritional value, and cooking quality in three different rice genotypes, transaminase activities and AA levels in grains during GF stage and the traits that significantly affected rice quality (physical appearance, cooking quality, and nutritional value) were analyzed. LL did not disturb transamination in rice grains during GF stage, as minimal impact was found on alanine and aspartate transaminase activities. Nevertheless, most AAs in caryopses, including lysine and threonine, increased in response to LL, except for sulfur-containing AAs. These results suggest that AA metabolism and accumulation in rice grains were rarely suppressed by LL during GF stage. Rice nutritional ingredients at harvest, such as major protein components including glutelin and most important essential amino acids (EAAs) including lysine and threonine, increased significantly in response to LL, whereas most protein and EAA ratios were rarely affected. However, LL markedly affected physical appearance of rice grains by reducing brown rice rate, milled rice rate, and 1000-grain weight and increasing the chalkiness rate. In addition, cooking qualities decreased in response to LL, while breakdown values and amylose levels decreased and setback values increased. We concluded that LL during GF stage decreased the cooking quality of rice, but could potentially improve the nutritional value of rice.

Inter-relationship among nutritional quality parameters of maize (Zea mays) genotypes

The present study was taken up to understand the inter-relationship among various nutritional components of maize (Zea mays L.) kernel. For this purpose, 23 elite maize genotypes received from different centres of All India Coordinated Research Projects on Maize during 2009 and 2010 were used. The samples were ground to powder and processed for the estimation of various nutritional quality parameters such as protein quality, starch, oil and carotenoids and the data was correlated to find the interrelationship between these components. The results showed that the protein content exhibited a significant negative correlation with two important essential amino acids such as tryptophan and lysine. An inverse correlation was found between starch and oil indicating that breeding for high oil maize may lead to lower grain yield. A significant positive correlation was observed between oil content and 100-kernel weight postulating that although increase in oil down-regulate the starch content, the total grain yield, however, would remain unaffected. Protein content showed a non-significant negative correlation with 100-kernel weight. A significant positive correlation was noticed between protein and starch. Another important finding of this study is the positive correlation observed between oil and fat soluble total carotenoids. Breeding for high oil, therefore, would have the added advantage of biofortification of maize. The findings will help to develop improved maize having an answer to better nutrition.