共查询到20条相似文献,搜索用时 15 毫秒
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Carlos I. Rivas-Vela Silvia L. Amaya-Llano Eduardo Castao-Tostado Gustavo A. Castillo-Herrera 《Molecules (Basel, Switzerland)》2021,26(21)
The importance of bioactive peptides lies in their diverse applications in the pharmaceutical and food industries. In addition, they have been projected as allies in the control and prevention of certain diseases due to their associated antioxidant, antihypertensive, or hypoglycemic activities, just to mention a few. Obtaining these peptides has been performed traditionally by fermentation processes or enzymatic hydrolysis. In recent years, the use of supercritical fluid technology, specifically subcritical water (SW), has been positioned as an efficient and sustainable alternative to obtain peptides from various protein sources. This review presents and discusses updated research reports on the use of subcritical water to obtain bioactive peptides, its hydrolysis mechanism, and the experimental designs used for the study of effects from factors involved in the hydrolysis process. The aim was to promote obtaining peptides by green technology and to clarify perspectives that still need to be explored in the use of subcritical water in protein hydrolysis. 相似文献
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Alex Sudakow Dr. Uli Papke Prof. Dr. Thomas Lindel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10223-10226
A novel photoarylation of amino acids and peptides is described, which tolerates the presence of water. Irradiation of Boc‐protected amino acids in the presence of N‐protected 2‐azidobenzimidazoles leads to selective arylation of carboxy termini or side chains. The new reaction also works for peptides. Irradiation of the nonapeptide H‐SPSYVYHQF‐OH also resulted in selective arylation of the tyrosine side chains, as indicated by ESI‐MS/MS fragmentation. Chemo‐ and regioselectivity could add the title reaction to the repertoire of photoaffinity labeling methods. 相似文献
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Metallomicelles as the model of hydrolytic metalloenzymes have begun recently1. Examples are the metal-ion complexes of lipophilic imidazoles2 and pyridines3 co-micelled with surfactants. Herein we report the complexes of a novel macrocyclic 12-membered di-oxotetraamine ligand bearing bis-hydroxy groups as functional pendants which can mimic the catalytic function of carboxypeptidase A in micellar media. 相似文献
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A study of the hydrolysis of adiponitrile (ADN) was performed in subcritical water to research the dependence on experimental
conditions. An L25(56) orthogonal array design (OAD) with six factors at five levels using statistical analysis was employed to optimize the experimental
conditions for each product in which the interactions between the variables were temporarily neglected. The six factors were
adiponitrile concentration (ADN c, wt%), temperature (T), time (t h), percentage of additives (reactant/additive, wt/wt%), additives (A), and pressure (p, MPa). The effects of these parameters were investigated using the analysis of variance (ANOVA) to determine the relationship
between experimental conditions and yield levels of different products. The results showed that (ADN c) and T had a significant influence on the yields of adipamide, adipamic acid, and adipic acid at p<0.05. Time was the statistically significant factor for the yield of 5-cyanovalermic acid at p<0.05 and (ADN c) was the significant factor for the yield of 5-cyanovaleramide at p<0.1. Finally, five supplementary experiments were conducted under optimized conditions predicted by the Taguchi method; the
results showed that the yield obtained of each product was no lower than that of the highest in the 25 experiments. Carbon
balance was calculated to demonstrate the validity of the experimental technique and the reliability of the results. Based
on the experimental results, a possible reaction mechanism was proposed. 相似文献
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《液相色谱法及相关技术杂志》2012,35(14):2757-2769
Abstract Microwave-induced acid hydrolysis was performed with isolated peptides on TLC layers. This vapor phase method was compared to solution phase techniques. A mechanistic study of peptide bond clevage was carried out by varying exposure conditions and reaction time. Acid hydrolysis products were identified by ninhydrin visualization. Also, TLC and TLC/MS were used to elucidate hydrolysis mechanisms. 相似文献
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蛋白质水解阶段对氨基酸组成分析的影响 总被引:10,自引:0,他引:10
水解是蛋白质氨基酸组成分析的重要步骤,水解质量的好坏直接影响到分析结果的正确与否,蛋白质的水解受到很多因素的影响,如温度,时间、水解试剂,添加剂,水解方法等,本文对近10年来蛋白质组成分析中中有关蛋白质水解问题的研究进进行了评述,对最近几年出现的一些新的水解方法如酸性水解中的气相水解,微波辐射水解,膜上蛋白质和印迹水解,聚丙烯酰安凝胶中蛋白质的水解,敏感氨基酸的水解以及水解过程中影响氨基酸外消旋化的因素等作了简要的介绍。 相似文献
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Dhanya Karipal Padinjare Veedu Prof. Luke A. Connal Assoc. Prof. Lara R. Malins 《Angewandte Chemie (International ed. in English)》2023,62(4):e202215470
Electrochemical transformations provide enticing opportunities for programmable, residue-specific peptide modifications. Herein, we harness the potential of amidic side-chains as underutilized handles for late-stage modification through the development of an electroauxiliary-assisted oxidation of glutamine residues within unprotected peptides. Glutamine building blocks bearing electroactive side-chain N,S-acetals are incorporated into peptides using standard Fmoc-SPPS. Anodic oxidation of the electroauxiliary in the presence of diverse alcohol nucleophiles enables the installation of high-value N,O-acetal functionalities. Proof-of-principle for an electrochemical peptide stapling protocol, as well as the functionalization of dynorphin B, an endogenous opioid peptide, demonstrates the applicability of the method to intricate peptide systems. Finally, the site-selective and tunable electrochemical modification of a peptide bearing two discretely oxidizable sites is achieved. 相似文献
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水溶液中磷酰基促进的成肽反应研究沙耀武,巨勇,赵玉芬(清华大学化学系,北京,100084)关键词磷酰化组氨酸,成肽,水溶液一些氨基酸在前生化时期的条件下,就可以由甲烷、氨和水通过高压放电生成[1,2]。如果向该反应体系中加入三氢化磷,生成的氨基酸的种... 相似文献
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An improved method for the synthesis of enantiomerically pure isonitriles from amino acid esters and dipeptides is described. 相似文献
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Catalytic Hydrolysis of Lipophilic Amino Acid Esters by Metallomicelles as Carboxypeptidase A Models
Metallondcellesasthemodelofhydrolyticmetalloenzymes.havebegunrecently'.Exam-plesarethemetal-ioncomplexesoflipophilicinddazoles2andpyridines'co-ndcelledwithsurfactantS.Hereinwereportthecomplexesofanovelmacrocyclicl2-membereddioxotetradrineligandbearingbis-hydroxygroupsasfunctionalpendantSwhichcanmindcthecatalyticfunctionofcarboxypeptidaseAinndcellarmedia.2,6-Dioxo-l,4,7,lo-tetraazacyclo1(O.2Og,1.onuno1)'anddodecylglycidylether(O.54g,2.2nunol)'wererefluxedinEtOH(3OoInL)for24h.Thesolventwase… 相似文献
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In this work, a non‐natural amino acid, H‐propargylglycine‐OH (Pra), is chosen to examine the side‐chain effect on the backbone conformation of small peptides. The conformations of two synthesized Pra‐containing tripeptides, Ac‐Pra‐Pra‐NH2 (PPTP) and Ac‐Pra‐Ala‐NH2 (PATP), are examined by infrared (IR) spectroscopy in combination with molecular dynamics (MD) simulations and quantum chemical computations. By analyzing the joint distributions of backbone torsional angles, several significant conformations can be identified for the two tripeptides solvated in D2O. At room temperature, 44 % of PPTP exists in the α‐α conformation and 33 % of PATP exists in the α‐polyproline‐II conformation. Larger structural inhomogeneity is seen in both cases by MD simulations at elevated temperatures. Thus even a small side chain, such as the propargyl group can significantly alter the peptide backbone conformations. The results suggest that there is no overwhelming conformational propensity of the Pra residue in short peptides. IR spectra simulated in the amide‐I region using two different methods, reasonably reproduce the experimental IR spectra and their temperature dependence. 相似文献
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Asakawa D Moriguchi S Takayama M 《Journal of the American Society for Mass Spectrometry》2012,23(1):108-115
The influence of arginine (Arg), lysine (Lys), and phenylalanine (Phe) residues and phosphorylation on the molecular ion yields
of model peptides have been quantitatively studied using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry
in both positive- and negative-ion mode. The results obtained from these experiments have been interpreted from the standpoint
of two different components, namely, desorption and ionization, on the basis of the physicochemical properties of constituent
amino acids of the model peptides. The presence of basic residues such as Arg and Lys enhanced the ion yields of protonated
molecules [M + H]+. An N-terminal rather than a C-terminal Arg residue was advantageous for the formation of both [M + H]+ and [M – H]–. The presence of the Phe residue resulted in the increase of the ion yields of both [M + H]+ and [M – H]–. In contrast, the presence of phosphate group(s) contributed to the suppression of the yields of both [M + H]+ and [M – H]– due to the loss of phosphate group. The detection limits for both [M + H]+ and [M – H]– of model peptides have been evaluated. 相似文献