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Journal articles on the topic 'Alanine Amino acids Vetch Infrared spectroscopy'
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Parker, Stewart F., and Parvez I. Haris. "Inelastic neutron scattering spectroscopy of amino acids." Spectroscopy 22, no. 4 (2008): 297–307. http://dx.doi.org/10.1155/2008/815790.
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A combination of infrared, Raman and inelastic neutron scattering (INS) spectroscopies are used to provide complete vibrational spectra of several amino acids and dipeptides. The amino acids studied were glycine, alanine, glutamine, cysteine, methionine and phenylalanine and the dipeptides studied were Gly–Gln and Gly–Ala. The findings of this study have shown how the complementarity of infrared, Raman and INS spectroscopies can be exploited to provide complete vibrational spectra of amino acids and peptides. In particular, the strengths of INS spectroscopy are highlighted: the absence of selection rules, that hydrogenic motions are emphasised, the ready access to the low energy regime (<400 cm−1) and the straightforward calculation of intensities. In the future, it should be possible to apply this approach to the study of larger peptides as well as proteins.
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Ihs, A., B. Liedberg, K. Uvdal, C. Törnkvist, P. Bodö, and I. Lundström. "Infrared and photoelectron spectroscopy of amino acids on copper: Glycine, l-alanine and β-alanine." Journal of Colloid and Interface Science 140, no. 1 (November 1990): 192–206. http://dx.doi.org/10.1016/0021-9797(90)90335-l.
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El-Haramein, F. Jaby, A. Abd-El Moneim, H. Nakkoul, and P. C. Williams. "Prediction of the Neuro-Toxin Beta-N-Oxalyl-Amino-L-Alanine in Lathyrus Species, Using near Infrared Reflectance Spectroscopy." Journal of Near Infrared Spectroscopy 6, A (January 1998): A93—A96. http://dx.doi.org/10.1255/jnirs.173.
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Grasspea or chickling vetch ( Lathyrus spp.) is a common food legume, widely grown and eaten in northern India, Bangladesh, Pakistan, Nepal and Ethiopia. It contains the neurotoxin beta-N-oxalyl-amino-L-alanine (BOAA), which can cause the disease known as “neuro-lathyrism”, an irreversible paralysis of the lower limbs, if BOAA-rich seeds form a large proportion of the diet. Lathyrus is a drought-tolerant crop, and ICARDA seeks to breed high-yielding lines that are low in BOAA. Conventional methods for determination of BOAA are time-consuming, expensive, and not practicable for screening large numbers of genotypes. Near infrared (NIR) reflectance spectroscopy offers a rapid, inexpensive method of analysis. Application of NIR reflectance spectroscopy to the prediction of BOAA in Lathyrus has been achieved by developing NIR reflectance spectroscopy equations involving 88 samples, which represented three species: L. sativus, L. cicera and L. ochrus. Both intact and ground seeds were studied. Content of BOAA ranged from 0.09 to 0.83%. Seeds of L. cicera were significantly lower than those of the other two species. The best results were obtained from whole seeds, using multiple linear regression. The standard error of prediction of 0.05% and coefficient of determination ( r2) of 0.94 are considered quite adequate for use in the Lathyrus breeding programme.
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Kamei, Shun, Jigen Hibi, Yoshiyuki Ohtsubo, Hiroshi Watanabe, and Shin-ichi Kimura. "Infrared Evaluation of Enantiometric Amount and Application to Racemization at the Interface Between L- and D-Alanine." Applied Spectroscopy 72, no. 7 (April 20, 2018): 1074–79. http://dx.doi.org/10.1177/0003702818770575.
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Amino acids, except for glycine, have two types of molecular structures, L- and D-forms, which are enantiomers. As the L- and D-form molecules have identical chemical and physical properties, they cannot be easily identified by conventional methods. In this study, we found that the amount and the spatial distribution of D-enantiomers in an L-alanine (CH3CH(COOH)NH2) matrix in evaporated thin films, which is one of amino acid molecules, can be evaluated quantitatively using an infrared micro spectroscopy with synchrotron radiation. This method was applied to the evaluation of the volume fraction of a racemic component appearing at the interface between L- and D-alanine thin films.
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Nechifor, Aurelia Cristina, Andreia Pîrțac, Paul Constantin Albu, Alexandra Raluca Grosu, Florina Dumitru, Ioana Alina Dimulescu (Nica), Ovidiu Oprea, Dumitru Pașcu, Gheorghe Nechifor, and Simona Gabriela Bungău. "Recuperative Amino Acids Separation through Cellulose Derivative Membranes with Microporous Polypropylene Fiber Matrix." Membranes 11, no. 6 (June 5, 2021): 429. http://dx.doi.org/10.3390/membranes11060429.
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The separation, concentration and transport of the amino acids through membranes have been continuously developed due to the multitude of interest amino acids of interest and the sources from which they must be recovered. At the same time, the types of membranes used in the sepa-ration of the amino acids are the most diverse: liquids, ion exchangers, inorganic, polymeric or composites. This paper addresses the recuperative separation of three amino acids (alanine, phe-nylalanine, and methionine) using membranes from cellulosic derivatives in polypropylene ma-trix. The microfiltration membranes (polypropylene hollow fibers) were impregnated with solu-tions of some cellulosic derivatives: cellulose acetate, 2-hydroxyethyl-cellulose, methyl 2-hydroxyethyl-celluloseand sodium carboxymethyl-cellulose. The obtained membranes were characterized in terms of the separation performance of the amino acids considered (retention, flux, and selectivity) and from a morphological and structural point of view: scanning electron microscopy (SEM), high resolution SEM (HR-SEM), Fourier transform infrared spectroscopy (FT-IR), energy dispersive spectroscopy (EDS) and thermal gravimetric analyzer (TGA). The re-sults obtained show that phenylalanine has the highest fluxes through all four types of mem-branes, followed by methionine and alanine. Of the four kinds of membrane, the most suitable for recuperative separation of the considered amino acids are those based on cellulose acetate and methyl 2-hydroxyethyl-cellulose.
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Nosrati, Hamed, Hossein Hamzehei, Saeed Afroogh, Seyedeh Ashabi, Elahe Attari, and Hamidreza Manjili. "Phenyl alanine & Tyrosine Amino acids Coated Magnetic Nanoparticles: Preparation and Toxicity study." Drug Research 69, no. 05 (September 6, 2018): 277–83. http://dx.doi.org/10.1055/a-0664-0431.
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AbstractIn this study we reported the synthesis of L-phenyl alanine (Phe) & L-tyrosine (Tyr) Natural Amino acids coated iron oxide magnetic nanoparticles under one-pot and in situ reaction. Functionalized iron oxide magnetic nanoparticles were characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Vibrating Sample Magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) techniques. Cellular toxicity of amino acids coated iron oxide magnetic nanoparticles was also investigated on HEK-293 cell lines. Additionally, a hemolysis test of as prepared magnetic nanoparticles were performed. It was found that the synthesized Phe and Tyr coated magnetic nanoparticles (F@Phe NPs and F@Tyr NPs) were spherical in shape with an average size less than 25 nm, also the saturation magnetization (Ms) of the F@Phe NPs and F@Tyr NPs were about 30.02 and 58.23 emu/g, respectively, which was lower than those of bare Fe3O4. The TGA results show that apart from this weight loss, the coated sample shows a weight loss of 5.48, and 6.88% respectively corresponding to loss of Tyr, and Phe which is coated on the Fe3O4 nanoparticles. At a high concentration, less than 2.92 and 3.13% hemolytic activity were observed for F@Phe NPs and F@Tyr NPs, respectively. The F@Phe NPs and F@Tyr NPs show the possibility of using this nanoparticles in the development of in vitro and in vivo pharmaceutical and biomedical fields due to do not possess a toxic effect, good ζ-potential and related small and narrow size distribution.
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Hobart, David B., Michael A. G. Berg, Hannah M. Rogers, and Joseph S. Merola. "Synthesis, Characterization, and Non-Covalent Interactions of Palladium(II)-Amino Acid Complexes." Molecules 26, no. 14 (July 17, 2021): 4331. http://dx.doi.org/10.3390/molecules26144331.
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The reaction of palladium(II) acetate with acyclic amino acids in acetone/water yields square planar bis-chelated palladium amino acid complexes that exhibit interesting non-covalent interactions. In all cases, complexes were examined by multiple spectroscopic techniques, especially HRMS (high resolution mass spectrometry), IR (infrared spectroscopy), and 1H NMR (nuclear magnetic resonance) spectroscopy. In some cases, suitable crystals for single crystal X-ray diffraction were able to be grown and the molecular structure was obtained. The molecular geometries of the products are discussed. Except for the alanine complex, all complexes incorporate water molecules into the extended lattice and exhibit N-H···O and/or O···(HOH)···O hydrogen bonding interactions. The non-covalent interactions are discussed in terms of the extended lattice structures exhibited by the structures.
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Vialykh, E. A., S. A. Ilarionov, H. M. Abdelrahman, and I. A. Vialykh. "Changes in amino acids content of humic acids sequentially extracted from peat and sod–Podzolic soil." Canadian Journal of Soil Science 94, no. 5 (November 2014): 575–83. http://dx.doi.org/10.4141/cjss2013-064.
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Vialykh, E. A., Ilarionov, S. A., Abdelrahman, H. M. and Vialykh, I. A. 2014. Changes in amino acids content of humic acids sequentially extracted from peat and sod–Podzolic soil. Can. J. Soil Sci. 94: 575–583. Amino acids (AA) and peptides are thought to be part of humic acids (HA), but debate whether they are an integral part of the HA is still going. Humic acids sequentially extracted from peat and sod-podzolic soil were analyzed for their AA content, elemental composition and by Fourier transform infrared spectroscopy. Extracted HA were hydrolyzed in 6 M HCl for 16 h for AA release, which was detected by a capillary electrophoresis system. Alanine, arginine, sum of aspartic acid and asparagine, sum of cysteic acid and cysteine, sum of glutamic acid and glutamine, glycine, histidine, leucine and isoleucine, lysine, methionine, phenylalanine, proline, serine, threonine, tyrosine, valine were identified. The total content of hydrolyzable AA in sod-Podzol HA increased by 6.2–8.2% with increasing the extraction cycles while an inverse tendency was observed for AA released from peat HA. Moreover, individual AA expressed as percentages of total AA were constant values with coefficients of variation lower than 20% for the studied HA.
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Naglah, Ahmed M., Mohamed A. Al-Omar, Abdulrahman A. Almehizia, Ahmad J. Obaidullah, Mashooq A. Bhat, Nasser S. Al-Shakliah, Kaouther Belgacem, Badriah M. Majrashi, Moamen S. Refat, and Abdel Majid A. Adam. "Synthesis, Spectroscopic, and Antimicrobial Study of Binary and Ternary Ruthenium(III) Complexes of Ofloxacin Drug and Amino Acids as Secondary Ligands." Crystals 10, no. 3 (March 20, 2020): 225. http://dx.doi.org/10.3390/cryst10030225.
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This article aimed to synthesis, spectroscopic, physicochemical characterizations, and catalytic studies on some ofloxacin (OFL) complexes with ruthenium(III) [Ru(III)] metal ions. The Ru(III)-OFL complex, [Ru(OFL)2(Cl)2]Cl and two mixed-ligand complexes, [Ru(OFL)(AA)(H2O)2]Cl2 derived from OFL as the primary ligand and amino acids [AA; either glycine (Gly) or alanine (Ala)] as the secondary ligands, were synthesized and characterized using microanalytical, spectroscopic, and physical techniques including element composition, molar conductivity, infrared, electronic spectra, thermal, X-ray powder diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), Scanning electron microscopy (SEM), and Transmittance electron microscopy (TEM) analyses. The element analysis data describe the formation of 1:2 [Ru(III):OFL] and 1:1:1 [Ru(III):OFL:AA] complexes. The octahedral geometry of the complexes was confirmed by their magnetic moment and diffused reflectance. Fourier Transform Infrared spectroscopic (FTIR) measurements suggested that the ligands chelated with Ru(III) ions through the nitrogen atoms of the piperazine ring. In vitro antibacterial efficiency of the OFL compounds was evaluated by paper disc diffusion method. Significant antimicrobial activities were observed for some compounds of the series.
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Miranda, Luis F. C., Rogéria R. Gonçalves, and Maria E. C. Queiroz. "A Dual Ligand Sol–Gel Organic-Silica Hybrid Monolithic Capillary for In-Tube SPME-MS/MS to Determine Amino Acids in Plasma Samples." Molecules 24, no. 9 (April 27, 2019): 1658. http://dx.doi.org/10.3390/molecules24091658.
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This work describes the direct coupling of the in-tube solid-phase microextraction (in-tube SPME) technique to a tandem mass spectrometry system (MS/MS) to determine amino acids (AA) and neurotransmitters (NT) (alanine, serine, isoleucine, leucine, aspartic acid, glutamic acid, lysine, methionine, tyrosine, and tryptophan) in plasma samples from schizophrenic patients. An innovative organic-silica hybrid monolithic capillary with bifunctional groups (amino and cyano) was developed and evaluated as an extraction device for in-tube SPME. The morphological and structural aspects of the monolithic phase were evaluated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), nitrogen sorption experiments, X-ray diffraction (XRD) analyses, and adsorption experiments. In-tube SPME-MS/MS conditions were established to remove matrix, enrich analytes (monolithic capillary) and improve the sensitivity of the MS/MS system. The proposed method was linear from 45 to 360 ng mL−1 for alanine, from 15 to 300 ng mL−1 for leucine and isoleucine, from 12 to 102 ng mL−1 for methionine, from 10 to 102 ng mL−1 for tyrosine, from 9 to 96 ng mL−1 for tryptophan, from 12 to 210 ng mL−1 for serine, from 12 to 90 ng mL−1 for glutamic acid, from 12 to 102 ng mL−1 for lysine, and from 6 to 36 ng mL−1 for aspartic acid. The precision of intra-assays and inter-assays presented CV values ranged from 1.6% to 14.0%. The accuracy of intra-assays and inter-assays presented RSE values from −11.0% to 13.8%, with the exception of the lower limit of quantification (LLOQ) values. The in-tube SPME-MS/MS method was successfully applied to determine the target AA and NT in plasma samples from schizophrenic patients.
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Tabandeh, Sara, and Lorraine Leon. "Engineering Peptide-Based Polyelectrolyte Complexes with Increased Hydrophobicity." Molecules 24, no. 5 (March 1, 2019): 868. http://dx.doi.org/10.3390/molecules24050868.
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Polyelectrolyte complexation is a versatile platform for the design of self-assembled materials. Here we use rational design to create ionic hydrophobically-patterned peptides that allow us to precisely explore the role of hydrophobicity on electrostatic self-assembly. Polycations and polyanions were designed and synthesized with an alternating sequence of d- and l-chiral patterns of lysine or glutamic acid with either glycine, alanine or leucine due to their increasing hydrophobicity index, respectively. Two motifs were considered for the oppositely charged patterned peptides; one with equal residues of charged and uncharged amino acids and the other with increased charge density. Mass spectroscopy, circular dichroism, H- and F-NMR spectroscopy were used to characterize the polypeptides. Polyelectrolyte complexes (PECs) formed using the sequences were characterized using turbidity measurements, optical microscopy and infrared spectroscopy. Our results show that the critical salt concentration, a key measure of PEC stability, increased with both increasing charge density as well as hydrophobicity. Furthermore, by increasing the hydrophobicity, the amount of PEC formed increased with temperature, contrary to purely ionic PECs. Lastly, we assessed the encapsulation behavior of these materials using a hydrophobic dye. Concluding that encapsulation efficiency increased with hydrophobic content of the complexes providing insight for future work on the application of these materials for drug delivery.
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Gouttenoire, Jérôme, Valérie Castet, Roland Montserret, Naveen Arora, Vincent Raussens, Jean-Marie Ruysschaert, Eric Diesis, Hubert E. Blum, François Penin, and Darius Moradpour. "Identification of a Novel Determinant for Membrane Association in Hepatitis C Virus Nonstructural Protein 4B." Journal of Virology 83, no. 12 (April 8, 2009): 6257–68. http://dx.doi.org/10.1128/jvi.02663-08.
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ABSTRACT Nonstructural protein 4B (NS4B) plays an essential role in the formation of the hepatitis C virus (HCV) replication complex. It is a relatively poorly characterized integral membrane protein predicted to comprise four transmembrane segments in its central portion. Here, we describe a novel determinant for membrane association represented by amino acids (aa) 40 to 69 in the N-terminal portion of NS4B. This segment was sufficient to target and tightly anchor the green fluorescent protein to cellular membranes, as assessed by fluorescence microscopy as well as membrane extraction and flotation analyses. Circular dichroism and nuclear magnetic resonance structural analyses showed that this segment comprises an amphipathic α-helix extending from aa 42 to 66. Attenuated total reflection infrared spectroscopy and glycosylation acceptor site tagging revealed that this amphipathic α-helix has the potential to traverse the phospholipid bilayer as a transmembrane segment, likely upon oligomerization. Alanine substitution of the fully conserved aromatic residues on the hydrophobic helix side abrogated membrane association of the segment comprising aa 40 to 69 and disrupted the formation of a functional replication complex. These results provide the first atomic resolution structure of an essential membrane-associated determinant of HCV NS4B.
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Proniewicz, Edyta, Grzegorz Burnat, Helena Domin, Izabela Małuch, Marta Makowska, and Adam Prahl. "Application of Alanine Scanning to Determination of Amino Acids Essential for Peptide Adsorption at the Solid/Solution Interface and Binding to the Receptor: Surface-Enhanced Raman/Infrared Spectroscopy versus Bioactivity Assays." Journal of Medicinal Chemistry 64, no. 12 (June 10, 2021): 8410–22. http://dx.doi.org/10.1021/acs.jmedchem.1c00397.
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Antón-Herrero, Rafael, Carlos García-Delgado, Begoña Mayans, Raquel Camacho-Arévalo, and Enrique Eymar. "Impact of New Micro Carbon Technology Based Fertilizers on Growth, Nutrient Efficiency and Root Cell Morphology of Capsicum annuum L." Agronomy 10, no. 8 (August 8, 2020): 1165. http://dx.doi.org/10.3390/agronomy10081165.
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The aim of this study was to determine the effects of new Micro Carbon Technology (MCT®) fertilizers based on humic acids biologically digested on the growth and development of pepper plants. In this work, the biostimulant effect of MCT® fertilizers was compared to conventional mineral fertilizers. In order to evaluate MCT® fertilizers, a previous chemical characterization (infrared spectroscopy, liquid chromatography and mass spectrometry) of seven MCT® fertilizers was performed. Two fertilization tests of pepper plants were carried out in hydroponic conditions, where the fertilization and the age of the plants were studied in order to evaluate the specific effects on roots and leaves. Plant weight and foliar analysis (chlorophyll indices and nutrients) have been determined. Transmission electron microscopy was used to visualize the morphological differences in the root and leaf cells. Comparison between conventional and MCT® based fertilizers showed that, with the MCT® fertilizers, the plant is exposed to the presence of free amino acids (Glycine and Alanine), polyphenols and humic substances. Although no significant differences were found in plant mass production, the plants fertilized with MCT® products presented better nutritional status than plants treated with conventional fertilization in terms of nutrient content in leaves. Important morphological differences in root cells were found. A large central vacuole that represented the 68–83% of the total root cell area was shown if the MCT® products were used, suggesting significant changes of membrane permeability in terms of water adsorption and consequently nutrient storage. The morphological differences observed in the root cells were more noticeable in adult plants.
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Mohammed, Mohammed H., Firas Aziz Rahi, and Hasanain Amer Naji. "Synthesis and Preliminary Kinetic Study of 5-fluorouracil Derivatives for Targeting Colon Tumor." JOURNAL OF ADVANCES IN CHEMISTRY 7, no. 1 (April 19, 2011): 1175–83. http://dx.doi.org/10.24297/jac.v7i1.973.
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5-Fluorouracil (5-FU) is used widely as an anticancer drug to treat solid cancers, such as colon, breast, rectal, and pancreatic cancers; although it’s clinical application is greatly limited by its short plasma half-life, poor tumor affinity, myelosuppression, and gastrointestinal toxicity. To tackle these problems, numerous modifications of the 5- Fu structure have been performed.Thus, 5-Fu as possible colon specific prodrugs were synthesized in which 5-Fu is attached to amino acids (alanine & phenylalanine) using succinate group as a spacer via amide or ester bond. An approach to improve the properties of 5-fluorouracil is the chemical transformation into bioreversible derivatives (prodrugs) which are converted to the parent drug by enzymatic and / or chemical hydrolysis. The synthesis of the target compounds were accomplished following multistep reaction procedures, the chemical reaction followed up and the purity of the products were checked by TLC. The structures of the final compounds were confirmed by their melting points, infrared spectroscopy and 1H-NMR spectra. The hydrolysis of compounds III, IV, V, and VI in aqueous buffer solutions of pH 1.2 and pH 7.4 were studied. Compounds III, IV, V and VI had enough stability at pH 1.2 (t = 429.874min, t =429.874min, t=334.336min and t =376.139min respectively) and at pH 7.4 (t=601.823min, t=601.823min, t=429.874min and t=501.519min respectively); expecting that hydrolysis of these compounds by microbial enzymes in the colon will deliver 5-fluorouracil spontaneously.
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Puri, Aamarpali Ratna. "Estimation of Alanine and Glycine in Cane Juice Using Near Infrared Spectroscopy." International Journal of Food Engineering 3, no. 1 (March 26, 2007). http://dx.doi.org/10.2202/1556-3758.1140.
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The ICUMSA or AOAC (Association of Official Agricultural Chemists) traditional test methods for testing individual constituents, pol and brix, are time consuming, operator dependent and involve the use of hazardous chemicals. The increased awareness of environmental and health topics makes it desirable to avoid the clarification of cane juice with basic lead acetate. Widely used in the food and agricultural industries, Near Infrared Spectroscopy NIR has now made considerable inroads into the more lengthy and wet chemistry procedures. Near Infrared is the region of combination bands and overtones due to interatomic forces. Hydrogenic atoms being the lightest vibrate within the near infrared region due to N-H, O-H and C-H groups. These are common atoms present within most food products. As near infrared wavelengths are specific, individual components can be identified so it can be used for quantitative analysis of phosphates, silicates and amino acids in cane juice. Amino acids are important as they, along with other nitrogenous bodies, react with reducing sugars to form colored compounds. Analyzing amino acids in a sample can help solve color problem in sugar. Alanine and glycine are commonly found amino acids in sugarcane. In the present research the online estimation of alanine and glycine is done in cane juice using Near-Infrared spectroscopy. Near Infrared Spectrophotometer of Elico (India) range (600-2500nm) has been used in its transmittance mode in conjunction with two multivariate calibration procedures, i.e., Partial Least Square Regression analysis (PLSR) and Stepwise Multivariate Linear Regression analysis (SMLR) for the analysis of alanine and glycine in cane juice. Multi linear regression analysis was also carried out to find out the most correlating wavelengths along with the standard deviation.
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Mehta, CHABUKSWAR AR, and PREETI M. GANDHI. "SYNTHESIS AND EVALUATION OF AMINO ACID ESTER CONJUGATES OF HIV PROTEASE INHIBITOR." Asian Journal of Pharmaceutical and Clinical Research, May 24, 2019, 342–46. http://dx.doi.org/10.22159/ajpcr.2019.v12i6.33521.
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Objective: Ester conjugates of HIV protease inhibitor, lopinavir (LP) with various amino acids were synthesized to improve its physicochemical and pharmacokinetic profile and consequently therapeutic potential.
Materials and Methods: Conjugates of LP with amino acids; glycine, alanine, valine, and serine were prepared by dicyclohexylcarbodiimide coupling method. The synthesized compounds were characterized by nuclear magnetic resonance, mass, and Fourier-transform infrared spectroscopy and evaluated for their solubility, partition coefficient, hydrolytic stability, cytotoxicity, and permeability through Caco-2 cells.
Results: Aqueous solubility studies indicated significantly better solubility profiles of all conjugates as compared to LP. With respect to hydrolysis, all the conjugates displayed higher stability under acidic conditions while undergo hydrolysis with rise in pH. Conjugates did not exhibit cytotoxicity for concentration as high as 100 μg/ml, which indicates promising therapeutic potential. Absorptive diffusion of drug across Caco-2 cell monolayers was improved by amino acid conjugation.
Conclusion: Amino acid ester conjugates of LP not only showed better solubility but also significantly higher permeability than LP. Thus, direct conjugation of L-amino acids is a viable approach to improve oral absorption and thereby oral bioavailability of protease inhibitors.
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Zhang, Da, Jian Wu, Guan Li, and Chun Shi. "The screening and preliminary construction of quality mutant population for cultivar “Nipponbare” in japonica rice (Oryza sativa)." Biologia 67, no. 6 (January 1, 2012). http://dx.doi.org/10.2478/s11756-012-0106-x.
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AbstractProgenies of Oryza sativa cv. Nipponbare induced with 0.4% ethyl methane sulphonate (EMS) were screened for quality mutants and the preliminary quality mutant population was constructed in present experiment. A total of 2210 materials were first screened using near infrared reflectance spectroscopy (NIRS) from which 208 quality mutants were obtained for a second screening and then yielded 73 quality mutants including amylase content (AC), gel consistency (GC), gelatinization temperature (GT), protein content (PC), rapid viscosity analysis (RVA) parameters and amino acid contents. The screening yielded 11 PC mutants with a mutation frequency of 4.98‰, followed by 7 rice floury viscosity mutants (3.17‰), 5 AC mutants (2.26‰), 4 chalky mutants, GT and GC mutants (1.81‰), and 2 ASV mutants (0.9‰). The relative contents of 17 kinds of amino acid mutations, including 7 kinds for essential amino acids and 10 kinds for nonessential amino acids were identified. With the variation of 10% as the screening standard, mutants were obtained for lysine and leucine at 0.45‰ and for valine at 4.98‰, but no mutants were found for isoleucine, phenylalanine, threonine. For nonessential amino acids, mutants of glutamic (0.45‰), arginine (3.62‰), alanine (3.17‰), serine (0.45‰), glycine (0.45‰), tyrosine (1.81‰), proline (2.71‰), and histidine (0.45‰) were obtained, but none was found for aspartic, phenylalanine nor threonine. At 100% as the screening standard for methionine and cysteines, the mutation frequency of these two amino acid mutants were 0.9‰ and 4.98‰ respectively. Quality mutants in this preliminary library of rice could play important role in gene function and breeding of rice quality.
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Gladue, D. P., E. Largo, I. de la Arada, V. M. Aguilella, A. Alcaraz, J. L. R. Arrondo, L. G. Holinka, et al. "Molecular Characterization of the Viroporin Function of Foot-and-Mouth Disease Virus Nonstructural Protein 2B." Journal of Virology 92, no. 23 (September 19, 2018). http://dx.doi.org/10.1128/jvi.01360-18.
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ABSTRACTNonstructural protein 2B of foot-and-mouth disease (FMD) virus (FMDV) is comprised of a small, hydrophobic, 154-amino-acid protein. Structure-function analyses demonstrated that FMDV 2B is an ion channel-forming protein. Infrared spectroscopy measurements using partially overlapping peptides that spanned regions between amino acids 28 and 147 demonstrated the adoption of helical conformations in two putative transmembrane regions between residues 60 and 78 and between residues 119 and 147 and a third transmembrane region between residues 79 and 106, adopting a mainly extended structure. Using synthetic peptides, ion channel activity measurements in planar lipid bilayers and imaging of single giant unilamellar vesicles (GUVs) revealed the existence of two sequences endowed with membrane-porating activity: one spanning FMDV 2B residues 55 to 82 and the other spanning the C-terminal region of 2B from residues 99 to 147. Mapping the latter sequence identified residues 119 to 147 as being responsible for the activity. Experiments to assess the degree of insertion of the synthetic peptides in bilayers and the inclination angle adopted by each peptide regarding the membrane plane normal confirm that residues 55 to 82 and 119 to 147 of 2B actively insert as transmembrane helices. Using reverse genetics, a panel of 13 FMD recombinant mutant viruses was designed, which harbored nonconservative as well as alanine substitutions in critical amino acid residues in the area between amino acid residues 28 and 147. Alterations to any of these structures interfered with pore channel activity and the capacity of the protein to permeabilize the endoplasmic reticulum (ER) to calcium and were lethal for virus replication. Thus, FMDV 2B emerges as the first member of the viroporin family containing two distinct pore domains.IMPORTANCEFMDV nonstructural protein 2B is able to insert itself into cellular membranes to form a pore. This pore allows the passage of ions and small molecules through the membrane. In this study, we were able to show that both current and small molecules are able to pass though the pore made by 2B. We also discovered for the first time a virus with a pore-forming protein that contains two independent functional pores. By making mutations in our infectious clone of FMDV, we determined that mutations in either pore resulted in nonviable virus. This suggests that both pore-forming functions are independently required during FMDV infection.