Commercial Amino Acid Research Articles

Commercial amino acids for yield and its components of common bean Azufrado Reyna in Northern Sinaloa

Objective: To investigate the effect of foliar commercial amino acids on yield and its components of common bean Azufrado Reyna under field conditions. Design/methodology/approach: Randomized complete block design with four replicates and four treatments (three commercial amino acids and a control). Grain yield, aboveground biomass, number of pods and normal seeds per unit surface, number of grains per pod, number of normal seeds per pod, weight of 100 seeds, and individual weight of seed were evaluated. Results: All biostimulants influenced the increase in grain yield, aboveground biomass, number of normal pods and seeds per unit surface as well as the number of seeds per pod with respect to the control. Limitations on study/implications: The study only assessed the evaluation of agronomic variables; therefore, it is necessary the measurement of morpho-physiological traits that provide evidence about the benefits of foliar aminoacids on yield and the formation of each component under field conditions. Findings/conclusions: Foliar biostimulant application had a positive effect on grain yield and some of its components as compared to the control. The number of normal seeds per normal pod was the variable that showed the highest correlation with grain yield.

A classical peptide coupling approach for the total synthesis of simnotrelvir

The total synthesis of an oral small-molecule antiviral agent; a structure based developmental drug simnotrelvir has been accomplished. The synthesis involves readily accessible commercial amino acids L-tert-leucine, 4-hydroxy-l-proline and l-glutamic acid that are easily converted to the key intermediates and are coupled together following classical peptide coupling technique using HATU and NMM. One of the crucial step in the synthesis involved a one pot Boc-deprotection and trifluoroacetylation of tert-leucine amino acid moiety mediated by ZnCl2.

Liquid fertilizers produced by microwave-assisted acid hydrolysis of livestock and poultry wastes and their effects on hot pepper cultivation.

Liquid fertilizers (LFs) produced by microwave-assisted acid hydrolysis of livestock and poultry wastes were applied to potted hot pepper (Capsicum annuum L.) to evaluate their potential to be used as amino acid LFs. A preliminary experiment was conducted to determine the optimum acid-hydrolysis conditions for producing LFs from a mixture of pig hair and faeces (P) and another mixture of chicken feathers and faeces (C). Two LFs were produced under the optimum acid-hydrolysis conditions (acidification by sulphuric acid (7.5 mol L-1) in a microwave (200 W) for 90 minutes), and a commercial amino acid LF (Guo Guang (GG)) was used for comparison. P, C and GG fertilizers were tested in potted hot pepper cultivation at two doses, whereas no fertilizer application served as the control (CK). P and C fertilizers significantly increased the fruit yield compared with GG fertilizer, particularly at the higher dose. Moreover, the treatments improved the fruit vitamin C and soluble sugar contents in the order of C > P > GG compared with CK. These results could be attributed to more types of amino acids in C fertilizer than in P and GG fertilizers. The results also indicated that the prepared fertilizers could significantly increase the shoot and root dry weight, soil available nitrogen and phosphorus contents and nitrogen, phosphorus, and potassium (NPK) uptake by plants compared with CK. In conclusion, microwave-assisted acid hydrolysis could effectively convert unusable wastes into valuable fertilizers comparable or even superior to commercial fertilizers.

A Study of the Literature on Intrauterine Treatment Options for Chronic Placental Insufficiency with Intrauterine Growth Restriction Using Intrauterine Intravascular Amino Acid Supplementation.

Intrauterine growth retardation (IUGR) is a very serious prenatal condition with 3-5% incidence of all pregnancies. It results from numerous factors, including chronic placental insufficiency. IUGR is associated with an increased risk of mortality and morbidity and is considered a major cause of fetal mortality. Currently, treatment options are significantly limited and often result in preterm delivery. Postpartum, IUGR infants also have higher risks of disease and neurological abnormalities. The PubMed database was searched using the keywords "IUGR", "fetal growth restriction", "treatment", "management" and "placental insufficiency" for the period between 1975 and 2023. These terms were also combined together. There were 4160 papers, reviews and articles dealing with the topic of IUGR. In total, only 15 papers directly dealt with a prepartum therapy of IUGR; 10 of these were based on an animal model. Overall, the main focus was on maternal intravenous therapy with amino acids or intraamniotic infusion. Treatment methods have been tested since the 1970s to supplement the fetuses with nutrients lacking due to chronic placental insufficiency in various ways. In some studies, pregnant women were implanted with a subcutaneous intravascular perinatal port system, thus infusing the fetuses with a continuous amino acid solution. Prolongation of pregnancy was achieved, as well as improvement in fetal growth. However, insufficient benefit was observed in infusion with commercial amino acid solution in fetuses below 28 weeks' gestation. The authors attribute this primarily to the enormous variation in amino acid concentrations of the commercially available solutions compared with those observed in the plasma of preterm infants. These different concentrations are particularly important because differences in the fetal brain caused by metabolic changes have been demonstrated in the rabbit model. Several brain metabolites and amino acids were significantly decreased in IUGR brain tissue samples, resulting in abnormal neurodevelopment with decreased brain volume. There are currently only a few studies and case reports with correspondingly low case numbers. Most of the studies refer to prenatal treatment by supplementation of amino acids and nutrients to prolong pregnancy and support fetal growth. However, there is no infusion solution that matches the amino acid concentrations found in fetal plasma. The commercially available solutions have mismatched amino acid concentrations and have not shown sufficient benefit in fetuses below 28 weeks' gestation. More treatment avenues need to be explored and existing ones improved to better treat multifactorial IUGR fetuses.

2D/2D porous Co3O4/rGO nanosheets act as an electrochemical sensor for voltammetric tryptophan detection

Herein, 2D/2D porous Co3O4 nanosheets/rGO composites modified GCE (Co3O4/rGO/GCE) were proposed for electrochemical detection of tryptophan (Trp). The surface morphology and structure of Co3O4/rGO nanosheets were carried out using SEM, XRD, and Raman spectra. Electrochemical performance of Trp on as-synthesized modified electrodes were discussed by CV and EIS techniques. Moreover, the best electrochemical property was also investigated by varying test condition detailedly. Consequently, oxidation peak intensity and current density were 130.3 μA and 336.7 μA·cm−2 on Co3O4/rGO/GCE at working potential of 0.78 V (vs. SCE electrode), respectively. They were more than 23-times greater than these on bare GCE in electrochemical detection of Trp. It was attributed to the synergy effect of 2D porous Co3O4 nanosheets (high catalytic activity) and 2D rGO nanosheets (large electrochemical active area). After the optimization, wide linear determination ranges (from 1.0 to 800 μM) and low LOD of 0.26 μM (S/N = 3) were acquired. In addition, these electrodes were further successfully applied to the determination of Trp in commercial amino acid injection samples. This 2D porous Co3O4/rGO modified GCE sensor could provide a slight view on the design of 2D/2D composite materials with high electrochemical properties.

Enhancing surface functionalization of activated carbon using amino acids from natural source for CO2 capture

Amino acids-functionalized solid porous materials are promising adsorbents for CO2 capture but could not be considered economically viable for large scale application. This study investigated the feasibility of utilizing egg white as an alternative cheap source to commercial amino acids, as a surface modifier to enhance the adsorption capacity of palm shell activated carbon. The adsorbent was successfully prepared via facile activation process and was evaluated for its CO2 adsorption capacity using a fixed-bed column system. The effects of egg white loading, impregnation ratio, adsorption temperature, feed gas flow rate and CO2 inlet concentration were examined. The best sample prepared with 10 wt.% of egg white (ACEW-10) exhibited remarkable CO2 uptake enhancement by 76%, at 25 °C and 1 atm. Characterization study performed using scanning electron microscope, surface area and pore volume analyzer, elemental analyzer, Fourier transform infrared spectroscopy, temperature programmed desorption and thermogravimetric analysis evidently showed that increase in CO2 adsorption capacity was attributed to the introduction of amide functional group of egg white on the surfaces of activated carbon. The adsorbent demonstrated good recyclability over five consecutive adsorption–desorption cycles with >93% regeneration efficiency. All findings indicate that egg white-impregnated activated carbon is a promising green adsorbent for CO2 capture which further allows for potential reutilization of egg white industrial wastes. This research also aims to attract more researchers to explore on other possible natural sources of amino acids for the development of low-cost, sustainable and eco-friendly CO2 adsorbents.

Clinician Experience with Using Hypoallergenic Formulas to Treat Infants with Suspected Cow's Milk Protein Allergy: A Secondary Analysis of a Prospective Survey Cohort.

Cow's milk protein allergy (CMPA) is a common condition in infants, but little is known about healthcare providers' clinical experience treating infants with CMPA. To address this gap, we analyzed prospectively collected data from healthcare providers (HCPs) who treated infants under six months old with suspected CMPA using hypoallergenic formulas. The study focused on a commercial extensively hydrolyzed formula containing Lactobacillus rhamnosus GG (ATCC53103) (eHF-LGG) or a commercial amino acid formula (AAF). In this secondary analysis of prospectively collected survey data, 52 HCPs treated 329 infants under six months old with suspected CMPA using hypoallergenic formulas. A series of two de-identified surveys per patient were collected by HCPs to assess short-term symptom relief in the patients and HCP's satisfaction with the management strategies. The initial survey was completed at the initiation of treatment of CMPA, and the second survey was completed at a follow-up visit. The majority of HCPs (87%) in the study were general pediatricians, and most saw 2 to 10 CMPA patients weekly. Results showed that clinicians reported satisfaction with treatment in 95% of patients in the EHF cohort and 97% of patients in the AAF cohort and achieved expected clinical results in 93% and 97% of patients using eHF and AAF, respectively. Furthermore, few patients were switched from the hypoallergenic formula once initiated. The study provides new insights into HCP perspectives on treating infants with CMPA and supports using hypoallergenic formulas to manage this condition. However, additional prospective controlled studies are needed to confirm these initial findings.

ROLE OF AMINO ACIDS IN IMPROVING GROWTH, YIELD AND PHYSIOLOGICAL PARAMETERS OF SOME EGYPTIAN CLOVER CULTIVARS

The lack of green forage of good quality is considered the main constraints that contribute to the lack of livestock development. An experiment was performed at Sakha Agricultural Research Station Farm, Kafr El-Sheikh Governorate, Egypt, to study the role of spraying commercial amino acids (g-plus) and pure tryptophan on forage yield and chemical composition of three Egyptian clover cultivars during the two successive winter seasons 2019/2020 and 2020/2021.
 The experiment was laid out in a strip-plot design with three replications. The main plots were occupied by amino acids treatments i.e. spray with water (control), spray with g-plus (5cm/l water) and spray with tryptophan at two concentration (200 and 400 mg/l). While sub-plots contained three cultivars of berseem; Helaly, Serw1 and Giza 6. The results showed that, the maximum total fresh forage yield, total dry forage yield, average of plant height, number of stem per 0.25 m2, fresh leaf/stem percent and dry leaf/stem percent were obtained for variety Helaly spraying by amino acid g-plus (5cm/l water). Also, the obtained results showed that, foliar spraying of amino acids caused significant increase of most physiological characters in comparison to the control. The highest values of chlorophyll content, relative water content (RWC %), protein % and NPK% were obtained with spraying g-plus. Concerning, the cultivars effects showed a wide range of variation in their productivity where, Helaly was the highest values of the most physiological parameters as well as yield and yield components. The interaction effects of foliar spraying of amino acids and cultivars showed that, Helaly treated with g-plus (5cm/l) gave the highest values of growth and physiological parameters.

A ubiquitous amino acid source for prokaryotic and eukaryotic cell-free transcription-translation systems.

Cell-free gene expression (CFE) systems are an attractive tool for engineering within synthetic biology and for industrial production of high-value recombinant proteins. CFE reactions require a cell extract, energy system, amino acids, and DNA, to catalyse mRNA transcription and protein synthesis. To provide an amino acid source, CFE systems typically use a commercial standard, which is often proprietary. Herein we show that a range of common microbiology rich media (i.e., tryptone, peptone, yeast extract and casamino acids) unexpectedly provide an effective and low-cost amino acid source. We show that this approach is generalisable, by comparing batch variability and protein production in the following range of CFE systems: Escherichia coli (Rosetta™ 2 (DE3), BL21(DE3)), Streptomyces venezuelae and Pichia pastoris. In all CFE systems, we show equivalent or increased protein synthesis capacity upon replacement of the commercial amino acid source. In conclusion, we suggest rich microbiology media provides a new amino acid source for CFE systems with potential broad use in synthetic biology and industrial biotechnology applications.

Alkaline intracellular pH (pHi) increases mTORC1 and mTORC2 signaling through PI3K to promote protein synthesis and cell survival

The conserved kinase mTOR (mechanistic target of rapamycin) regulates cell metabolism and promotes cell growth, proliferation, and survival in response to diverse environmental cues (e.g., nutrients; growth factors; hormones). mTOR forms the catalytic core of two multiprotein complexes, mTORC1 and mTORC2, which possess unique downstream targets and cellular functions. While mTORC1 and mTORC2 often respond to distinct upstream cues, they share a requirement for PI3K in their activation by growth factors. While many studies agree that amino acids activate mTORC1 but not mTORC2, several studies reported paradoxical activation of mTORC2 by amino acids. We noted that stimulating amino acid starved cells with a commercial mixture of amino acids increased mTORC2‐dependent Akt S473 phosphorylation rapidly while re‐feeding cells with complete DMEM containing amino acids failed to do so. Interestingly, we found the pH of the commercial amino acid mixture to be ~ pH 10. Upon controlling for pH, stimulating starved cells with amino acids at pH 10 but not 7.4 increased mTORC2 signaling. Moreover, DMEM at alkaline pH was sufficient to increase mTORC2 catalytic activity and signaling. Using a fluorescent pH‐sensitive dye (cSNARF‐1‐AM) coupled to ratio‐metric live cell imaging, we confirmed that alkaline extracellular pH (pHe) translated into a rapid increase in intracellular pH (pHi). Moreover, blunting this increase with a pharmacological inhibitor of an H+ transporter attenuated the increase in mTORC2 signaling by pHe. Alkaline pHi also activated AMPK, a canonical sensor of energetic stress that promotes mTORC2 signaling, as reported previously by us. Functionally, we found that alkaline pHi attenuated apoptosis caused by growth factor withdrawal through activation of AMPK‐mTORC2 signaling. These results indicate that alkaline pHi augments mTORC2 signaling to promote cell survival, in part through AMPK. In the course of this work, we noted that pHi increased phosphorylation of several downstream targets of PI3K (e.g., Akt P‐T308 and P‐S473; S6K1 P‐T389 and P‐T229; PRAS40 P‐T246; Tsc2 P‐S939), suggesting that PI3K itself responds to changes in pHi. Indeed, alkaline pHi increased PI‐3’,4’,5’‐P3 levels in a manner sensitive to the PI3K inhibitor BYL‐719. Thus, alkaline pHi elevates PI3K activity, which increases both mTORC1 and mTORC2 signaling. Mechanistically, we found that activation of PI3K by alkaline pHi induced dissociation of Tsc2 from lysosomal membranes, thereby relieving TSC‐mediated suppression of Rheb, a mTORC1‐activating GTPase. Functionally, we found that activation of PI3K by alkaline pHi increased mTORC1‐mediated 4EBP1 phosphorylation, which initiates cap‐dependent translation by eIF4E. Alkaline pHi also increased mTORC1‐driven protein synthesis. Taken together, these findings reveal alkaline pHi as a previously unrecognized activator of PI3K‐mTORC1/2 signaling that promotes protein synthesis and cell survival. As elevated pHi represents an under‐appreciated hallmark of cancer cells, these findings suggest that by alkaline pHi sensing by the PI3K‐mTOR axis and AMPK‐mTORC2 axes may contribute to tumorigenesis.

Responses of Peppermint and Spearmint Crops to Excessive Biostimulant Application and Increased Salinity in a Closed Soilless Production System

A floating system was established in a heated glass greenhouse in order to investigate whether the effect of amino acids (0.25 or 0.50% of a commercial amino acid (AA) solution Amino16®) during peppermint and spearmint production on plant developmental and nutritional status may be in part attributed to salinity induced osmotic stress. For this reason, in some nutrient solutions, three levels of salinity were induced by adding 0, 10, or 20 mM NaCl. According to the results, it can be concluded that spearmint is mostly favored by the highest amino acid supplement of the nutrient solution (0.50%) in terms of a substantial improvement of the antioxidant nutritional quality (by up to 130%) at the expense of a reduced biomass production (by <30%). Enzymic antioxidant defense mechanism (APX and POD) was efficiently activated, preventing severe lipid peroxidation and the accumulation of reactive oxygen species such as H2O2 and maintaining the proline content at the normal levels. The osmotic stress that was induced by the excessive AA concentration and confirmed by the chlorophyl fluorescence variations was probably related to NH4+ excess supply in the growing media and was not associated with the elevated electrical conductivity in the solution. The absence of any adverse stressful consequences upon the addition of 20 mM NaCl may be attributed to the high salt tolerance of peppermint and spearmint species.

The effect of seed priming and foliar application of anti-stress materials on quantitative and qualitative yield of chickpea (Cicer arietinum L.) Adel cultivar under irrigation regimes

IntroductionThe chickpea is mainly cultivated in agricultural systems in arid and semi-arid regions and needs low input. Specifications such as the ability to fix nitrogen, deep rooting and the effective use of atmospheric depression have led the plant to play an important role in stabilizing crop production systems. On average chickpea seed contain 23% protein is highly digestible. Water deficit stress is the most important factor limiting the growth and agricultural products in arid and semi-arid regions of the world. Drought stress is one of the most important factors in grain yield reduction of chickpea during pod formation and grain filling. Amino acids facilitate the transfer of food in the vascular system by improving the permeability of the cell membrane. In plants under drought stress or salinity, proline is widely used as an osmotic regulator. In fact, amino acids are the main chain in the protein structure, and in turn, are effective in plant growth. Increased proline in chickpea leaves is a mechanism for osmotic adjustment under water stress conditions. Using the priming method is one of the methods for improving seed function and increasing the quality of seeds in adverse environmental conditions, In fact, priming shortens the time from planting to emergence and protects seed of harmful biotic and abiotic factors in the critical stage of seedling establishment. These treatments also result in the emergence of uniformity, resulting in a uniform establishment and improved yield in the crop. Materials and methodsIn order to study the effect of Anti-stress materials priming and foliar application on quantitative and qualitative yield of chickpea (Cicer arietinum) Adel cultivar under Irrigation regime an experiment was conducted at the Research Farm of Agriculture of Tarbiat Modares University as randomized complete block design arrangement in split plot with three replications. The main plots were included 1- optimal irrigation 2- Moderate Irrigation 3- severe Irrigation as withholding irrigation until depletion of 20, 45 and 70 percent of soil available water at root development zone respectively and then the plots were irrigated to field capacity from flowering to plant harvest. Priming and foliar application of anti-stress materials including proline, valine, alanine, commercial combination of amino acids and distilled water together with without anti-stress materials were randomized to the subplot units.ResultsThe results showed that priming and foliar application of anti-stress materials and optimal irrigation incresed the number of primary branches to the 58.31% and 36.38%, plant fresh weight to the 108.25% and 36.16%, chlorophyll a to the 40.90% and 68.35%, number of seeds/plant to the 74.48% and 34.66%, pod per plant to the 48.13% and 45.12%, duration of ripening to the 9.53% and 8.65, yield forage to the 30.56% and 39.44%, biological yield to the 65.16% and 44.82% in chekpea in compring with using severe irrigation and without priming and anti-stress materials foliar application treatments repectively. Also 1000 kernel weight and harvest index were increased %20.67 and 27.82% in optimal irrigation related to severe irrigation. Interaction effects between irrigation regimes and anti-stress materials on chlorophyll b showed that the highest rate chlorophyll b related to optimal irrigation with using commercial amino acids to to the 80% and the least it related to severe irrigation without anti-stress materials to the 24%. Application of amino acids was significant in most traits such as number of primary branches, plant fresh weight, chlorophyll a, chlorophyll b, Number of seeds/plant, pod per plant, duration of ripening, yield forage, biological yield. ConclusionDrought stress reduced photosynthesis and limited the amount of assimilate and thus reduced the yield and yield components In this experiment. In most cases, the application of priming and foliar application of amino acids had a positive effect on the traits, including number of primary branches, plant fresh weight, chlorophyll a, chlorophyll b, number of seeds/plant, pod per plant, duration of ripening, yield forage, biological yield at drought stress condition. Therefore, the use of amino acids, especially its commercial combination or proline, is recommended to reduce the effects of water deficit stress in the chickpea Adel cultivar.

Biomimetic Amino Acid Functionalized Phenazine Flow Batteries with Long Lifetime at Near-Neutral pH.

Aqueous organic redox flow batteries (AORFBs) are a promising electrochemical technology for large-scale energy storage. We report a biomimetic, ultra-stable AORFB utilizing an amino acid functionalized phenazine (AFP). A series of AFPs with various commercial amino acids at different substituted positions were synthesized and studied. 1,6-AFPs display much higher stability during cycling when compared to 2,7- and 1,8-AFPs. Mechanism investigations reveal that the reduced 2,7- and 1,8-AFPs tend to tautomerize and lose their reversible redox activities, while 1,6-AFPs possess ultra-high stability both in their oxidized and reduced states. By pairing 3,3'-(phenazine-1,6-diylbis(azanediyl))dipropionic acid (1,6-DPAP) with ferrocyanide at pH 8 with 1.0 M electron concentration, this flow battery exhibits an OCV of 1.15 V and an extremely low capacity fade rate of 0.5 % per year. These results show the importance of molecular engineering of redox-active organics for robust redox-flow batteries.

Biomimetic Amino Acid Functionalized Phenazine Flow Batteries with Long Lifetime at Near‐Neutral pH

AbstractAqueous organic redox flow batteries (AORFBs) are a promising electrochemical technology for large‐scale energy storage. We report a biomimetic, ultra‐stable AORFB utilizing an amino acid functionalized phenazine (AFP). A series of AFPs with various commercial amino acids at different substituted positions were synthesized and studied. 1,6‐AFPs display much higher stability during cycling when compared to 2,7‐ and 1,8‐AFPs. Mechanism investigations reveal that the reduced 2,7‐ and 1,8‐AFPs tend to tautomerize and lose their reversible redox activities, while 1,6‐AFPs possess ultra‐high stability both in their oxidized and reduced states. By pairing 3,3′‐(phenazine‐1,6‐diylbis(azanediyl))dipropionic acid (1,6‐DPAP) with ferrocyanide at pH 8 with 1.0 M electron concentration, this flow battery exhibits an OCV of 1.15 V and an extremely low capacity fade rate of 0.5 % per year. These results show the importance of molecular engineering of redox‐active organics for robust redox‐flow batteries.

A rapid and simple gas chromatographic method for direct determination of nicotinamide in commercial vitamins and tonic drinks

A simple and rapid method was developed to determine the presence of nicotinamide in tonic drinks using the megapore semi-polar column (CP-Sil 8 CB, 30 m x 0.53 mm) with direct injection gas chromatography. Direct quantitative analysis of nicotinamide in amino acid drinks, vitamin drinks, essence of chicken and tonic drinks was carried out without any sample pretreatment procedure. Water soluble compound 1,9-nonanediol was used as an internal standard. The detection limit for nicotinamide was 2-5 μg/mL. Recovery studies were performed using 1 mL of vitamin drink and tonic drink, each spiked with nicotinamide at 105.5, and 211.0 μg, respectively. The recoveries were found in the range of 94-99% and 93-108%, respectively. The coefficients of variation being less than 9.8%. Forty-two commercial amino acid drinks, vitamin drinks, essences of chicken and tonic drinks were analyzed with this method. The nicotinamide contents were found as: 131-246, 24-112, 0-134 and 0-263 μg/mL, respectively. These results indicated that, one bottle each of the amino acid drink, vitamin drink, essences of chicken and tonic drink contain nicotinamide levels of: 39-74, 5-22, 0-10 and 0-21 mg/bottle. The results also showed that in 12 out of 4 of commercial amino acid and vitamin drinks, the nicotinamide exceeded the ROC's acceptable daily intake (RNDA, 14.4 mg) level; and 3 out of 10 commercial tonic drinks exceeded the ROC's RNDA level for nicotinamide.

Continuous Process for the Production of Taurine from Monoethanolamine

Taurine, 2-aminoethane-1-sulfonic acid, is a commercial amino acid manufactured from either ethylene oxide or monoethanolamine (MEA). Taurine is a valuable nutritional additive that is widely used in the production of energy drinks, pet food, nutritional supplements, and infant formula. The industrial production of taurine from MEA is a two-step batch process in which the first step is the reaction of MEA with sulfuric acid to produce the ester 2-aminoethyl hydrogen sulfate (AES) and the second step is the reaction of AES with a sulfite reagent. This report summarizes the results of a study of the fundamental chemistry for this two-step MEA-based chemical route to taurine as well as the application of this fundamental understanding to a process design for a scalable and cost-advantaged continuous process that is capable of commercial-scale production of taurine on a multikiloton scale. In order to maximize taurine yields, the water formed during the first esterification step must be effectively removed to avoid equilibrium limitations on the conversions of MEA and sulfuric acid to form the solid AES intermediate product. For the second AES sulfonation step in aqueous medium, we found that operation above 100 °C under a moderate pressure of an inert gas resulted in significantly higher taurine yields (>80 mol %) compared to those reported in current commercial production technology (typically 55–65 mol %).

Evaluation of the incidence of acute nausea and vomiting after administration of an amino acid solution containing only arginine and lysine with lutetium Lu-177 dotatate.

12113 Background: Lutetium Lu-177 dotatate is used to treat patients with gastroenteropancreatic neuroendocrine tumors, and an amino acid (AA) solution must be administered concurrently to mitigate nephrotoxicity. AA solutions may lead to increased rates of nausea and vomiting (NV) due to the inclusion of unnecessary non-essential and essential AA. Methods: This study is a single academic center retrospective chart review from October 6th, 2015 to December 17th, 2019 evaluating the incidence of acute NV in adult patients after administration of an AA solution containing only arginine 25 grams and lysine 25 grams in 1 liter of normal saline (Arginine-Lysine amino acid [AL AA]) with lutetium Lu-177 dotatate. The incidence of acute NV will be compared to the historical incidence in patients administered Parenteral amino acids 10%, Aminosyn II 10% or Clinisol 15% (commercial AA). Secondary endpoints include the incidence of rescue anti-emetic usage and the percentage of patients that require interruption of the AA infusion. Acute NV are defined as any occurrence of NV within twenty-four hours of the AA infusion. Results: 53 patients received a total of 164 treatments with the AL AA, while 18 patients received a total of 48 treatments with the commercial AA. The AL AA significantly decreased the incidence of acute NV, the mean AA infusion time, the interruption of the AA infusion, and the utilization of rescue anti-emetics compared to the commercial AA (Table) in patients on lutetium Lu-177 dotatate. Conclusions: The study findings support the use of an AL AA to be administered concurrently with lutetium Lu-177 dotatate to minimize commercial AA related acute NV. [Table: see text]

2,3-Diaminopropanols Obtained from d-Serine as Intermediates in the Synthesis of Protected 2,3-l-Diaminopropanoic Acid (l-Dap) Methyl Esters.

A synthetic strategy for the preparation of two orthogonally protected methyl esters of the non-proteinogenic amino acid 2,3-l-diaminopropanoic acid (l-Dap) was developed. In these structures, the base-labile protecting group 9-fluorenylmethyloxycarbonyl (Fmoc) was paired to the p-toluensulfonyl (tosyl, Ts) or acid-labile tert-butyloxycarbonyl (Boc) moieties. The synthetic approach to protected l-Dap methyl esters uses appropriately masked 2,3-diaminopropanols, which are obtained via reductive amination of an aldehyde prepared from the commercial amino acid Nα-Fmoc-O-tert-butyl-d-serine, used as the starting material. Reductive amination is carried out with primary amines and sulfonamides, and the process is assisted by the Lewis acid Ti(OiPr)4. The required carboxyl group is installed by oxidizing the alcoholic function of 2,3-diaminopropanols bearing the tosyl or benzyl protecting group on the 3-NH2 site. The procedure can easily be applied using the crude product obtained after each step, minimizing the need for chromatographic purifications. Chirality of the carbon atom of the starting d-serine template is preserved throughout all synthetic steps.

Evaluation of tetraalkylammonium amino acid ionic liquids as chiral ligands in ligand-exchange capillary electrophoresis

The application of chiral ionic liquids (ILs) in capillary electrophoresis (CE) for enantioseparation has received considerable attention in the past few years; however, the use of chiral ILs as ligands in ligand-exchange capillary electrophoresis (LE-CE) has been reported only in a few papers. In this work, several tetraalkylammonium amino acid ILs (TAA-AAILs) including tetramethylammonium-l-arginine (TMA-l-Arg), tetramethylammonium-l-proline (TMA-l-Pro) and tetramethylammonium-l-glutamic acid (TMA-l-Glu) were first applied in LE-CE to act as chiral ligands for enantioseparation. The results show that TMA-l-Arg-is an excellent chiral ligand, and able to yield equal or even better resolutions (Rs) in much shorter migration times for most tested analytes compared with previously reported AAILs ligands or free l-Arg-ligand. Parameters of the new TAA-AAILs-based LE-CE system such as the alkane chain length of TAA-AAILs, ILs configuration, ILs concentration, the type and concentration of central metal ion, buffer pH and applied voltage were optimized. Satisfactory enantioseparations were achieved for most selected free- or dansyl-amino acids. The method was then successfully applied to the enantiomeric impurity test of a commercial amino acid sample. This work indicates that the application of TAA-AAILs as chiral ligands in LE-CE is of great potential for enantioseparation.

44 Amino acids in livestock: A historical perspective

Abstract The advent of commercially viable synthetic amino acids (AA) and least cost formulation (LCF) have fundamentally changed swine and poultry diets over the past 40 years. Amino acids can be produced by chemical synthesis, hydrolysis of intact proteins and fermentation. Chemical synthesis of AA was first reported by Strecker (1850). Discovery of glutamate as the basis of Umami taste category (1907) spurred commercial AA production by hydrolysis. The discovery of commercially viable fermentative production of glutamate, by Kyowa Hakko Kogyo Co. (1957), revolutionized AA production. Their parallel discovery of lysine (Lys) production, using a natural C. glutmanicum mutant subsequently followed. This led to further screening for bacterial mutants for threonine (Thr, 1961), tryptophan (Trp, 1972), valine (Val, 1959) and isoleucine (Ile, 1972). The next milestone occurred with development of the first main-frame LCF programs (1960s). The first commercial application of dietary AA involved methionine (Met) for poultry, followed closely by Lys in swine. Use of other synthetic AA was cost-prohibitive, but they served as research tools. The next revolution involved recombinant DNA technology (1980s), which dramatically increased AA yield and reduced production cost. Simultaneously, development of PC based LCF enabled cost effective formulation. Subsequently, growth-derived AA ratio’s emerged from the labs of Fuller (1989) and Baker (1992). Patent expirations in the late 1980s led to new companies that produced rapid advances in fermentation methods, with new recombinant strains. Production cost declined further for Lys (1988), and production efficiencies allowed Thr (1995) and Trp (2000) to enter commercial diets. Advances in fermentation technology have enabled production of all ten essential AA. Extensive AA displacement of protein supplements has led to an ever-expanding global tonnage of AA for food and pet animals. With routine addition of 4–6 AA in swine diets, we question whether non-essential AA nitrogen may emerge as limiting (essential).