期刊文献+

二次检索

题名
关键词
文摘
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到424篇文章
< 1 2 22 >
每页显示 20 50 100
Methods for the Determination of Stable Isotopes of Carbon and Nitrogen Directly in Valine, Proline, Glutamine, and Glutamic Acid
1
作者 Lamzira Farulava Levani Eliashvili +1 位作者 Vakhtang Betlemidze Bachana Sulava 《American Journal of Analytical Chemistry》 2023年第10期467-480,共14页
Amino acids are very important compounds for the body and are involved in important functions that keep us healthy. Amino acids are essential components such as valine, proline, glutamine and glutamic acid. They can b... Amino acids are very important compounds for the body and are involved in important functions that keep us healthy. Amino acids are essential components such as valine, proline, glutamine and glutamic acid. They can be synthesized either naturally or artificially. To examine the metabolism and regulate the synthesis process, compounds labeled with nitrogen or carbon isotopes need to be used. These isotopic compounds allow for more extensive research and enable studies that would otherwise be impossible. However, their use is dependent on the availability of simple, efficient methods for isotopic analysis. Currently, the determination of the atomic fraction of carbon and nitrogen isotopes is only possible through their conversion into molecular nitrogen or carbon monoxide or carbon dioxide. This leads to the loss of information about isotopic enrichment in specific centers of the molecule. This article explores a new direct approach to determining the atomic fraction of carbon and nitrogen isotopes in the isotope-modified or identical centers of these compounds. This method eliminates the transfer process and dilution due to nitrogen and carbon impurities. It is now possible to simultaneously determine the atomic fraction of nitrogen and carbon isotopes in the research substance. This method can be applied to amino acids, making it an effective tool for proposing new research methods. Several articles [1] [2] [3] have proposed similar methods for organic compounds and amino acids. 展开更多
关键词 VALINE PROLINE GLUTAMINE glutamic Acid Mass Spectrometer Mass Spectrum Ion Current INTENSITY Mass Lines Molecular and Fragment Ions
下载PDF
Adsorption of glutamic acid from aqueous solution with calcined layered double Mg-Fe-CO_3 hydroxide 被引量:1
2
作者 焦飞鹏 帅丽 +3 位作者 于金刚 蒋新宇 陈晓青 杜邵龙 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3971-3978,共8页
Layered double Mg-Fe-CO3 hydroxide (Mg-Fe-LDH) with a mole ratio of Mg to Fe of 3 was synthesized by coprecipitation method and calcined product Mg-Fe-CLDH was obtained by heating Mg-Fe-LDH at 500 ℃ for 6 h. The as... Layered double Mg-Fe-CO3 hydroxide (Mg-Fe-LDH) with a mole ratio of Mg to Fe of 3 was synthesized by coprecipitation method and calcined product Mg-Fe-CLDH was obtained by heating Mg-Fe-LDH at 500 ℃ for 6 h. The as prepared Mg-Fe-LDH and calcined Mg-Fe-CLDH were used for removal of glutamic acid (Glu) from aqueous solution, respectively. Batch studies were carried out to address various experimental parameters such as contact time, pH, initial glutamic acid (Glu) concentration, co-existing anions and temperature. Glu was removed effectively (99.9%) under the optimized experimental conditions with Mg-Fe-CLDH. The adsorption kinetics follows the Ho’s pseudo second-order model. Isotherms for adsorption with Mg-Fe-CLDH at different solution temperatures were well described using the Langmuir model with a good correlation coefficient. The intraparticle diffusion model fitted the data well, which suggests that the intraparticle diffusion is not only the rate-limiting step. 展开更多
关键词 calcined layered double hydroxides glutamic acid ADSORPTION
下载PDF
Research on Physical and Chemical Properties of Corynebacterium glutamicum in Fermentation Process of the Glucose of Wheat Starch
3
作者 黄继红 周靖波 欧歌 《Agricultural Science & Technology》 CAS 2013年第3期516-519,共4页
[Objective] This study aimed to investigate the physical and chemical char- acteristic of Corynebacterium glutamicum in fermentation process of the glucose of wheat starch. [Method] The purity of glutamic acid in ferm... [Objective] This study aimed to investigate the physical and chemical char- acteristic of Corynebacterium glutamicum in fermentation process of the glucose of wheat starch. [Method] The purity of glutamic acid in fermentation period, optical density and cell viability of bacteria were detected as indicators for regression com- parison and analysis. [Result] The relative error d=-3.316 6% within the experimental range of Warburg trace breathing apparatus and double function analyzer. The linear relationship was s1=(1-d)s2. During the fermentation process of the glucose of wheat starch, the average cell activity was 6.24 μA and the maximum cell activity was 6.61 μA. [Conclusion] Compared with optical density, cell viability can more accurate- ly reflect the physical and chemical properties of Corynebacterium glutamicum in fermentation process of the glucose of wheat starch. There was certain correlation between cell membrane phospholipids and cell viability. 展开更多
关键词 Glucose of wheat starch glutamic acid Cell viability Physical and chemical characteristic
下载PDF
Tanshinone IIa antagonizes spinal ischemia/reperfusion injury by interfering with upstream glutamic acid factors 被引量:2
4
作者 Li Zhang Xiang Lin +1 位作者 Weinan Liu Jianhua Lin 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第20期1573-1577,共5页
Based on the hypothesis that upstream factor inhibition results in better treatment effects than downstream factor inhibition,the present study interfered with glutamic acid(Glu)-released upstream factors,such as Gl... Based on the hypothesis that upstream factor inhibition results in better treatment effects than downstream factor inhibition,the present study interfered with glutamic acid(Glu)-released upstream factors,such as Glu transporter function and Na+-K+-adenosine triphosphatases(ATPase)activity relativly.Rats with spinal cord ischemia/reperfusion injury received intraperitoneal injections of tanshinone Ila and Glu uptake and Na+-K+-ATPase activity were increased.Results showed that tanshinone Ila influenced Glu-released upstream factors following spinal ischemia/reperfusion injury and protected against spinal ischemia/reperfusion injury. 展开更多
关键词 spinal cord ischemia/reperfusion injury TANSHINONE glutamic acid transporter Na+-K+-ATPase neural regeneration
下载PDF
Metal ion-binding properties of L-glutamic acid and L-aspartic acid, a comparative investigation 被引量:3
5
作者 S. A. A. Sajadi 《Natural Science》 2010年第2期85-90,共6页
A comparative research has been developed for acidity and stability constants of M(Glu)1, M(Asp)2 and M(Ttr)3 complexes, which have been determined by potentiometric pH titration. Depending on metal ion-binding proper... A comparative research has been developed for acidity and stability constants of M(Glu)1, M(Asp)2 and M(Ttr)3 complexes, which have been determined by potentiometric pH titration. Depending on metal ion-binding properties, vital differences in building complex were observed. The present study indicates that in M(Ttr) com-plexes, metal ions are arranged to the carboxyl groups, but in M(Glu) and M(Asp), some metal ions are able to build chelate over amine groups. The results mentioned-above demonstrate that for some M(Glu) and M(Asp) complexes, the stability constants are also largely determined by the affinity of metal ions for amine group. This leads to a kind of selectivity of metal ions, and transfers them through building complexes accompanied with glutamate and aspartate. For heavy metal ions, this building complex helps the absorption and filtration of the blood plasma, and consequently, the excursion of heavy metal ions takes place. This is an important method in micro-dialysis. In this study the different as-pects of stabilization of metal ion complexes regarding to Irving-Williams sequence have been investigated. 展开更多
关键词 glutamic ACID Aspartic ACID Tartaric ACID DIVALENT Metal Ions POTENTIOMETRIC TITRATION ACIDITY and Stability CONSTANTS
下载PDF
Sequential elevation of autoantibodies to thyroglobulin and glutamic acid decarboxylase in type 1 diabetes 被引量:1
6
作者 Eiji Kawasaki Jun-ichi Yasui +10 位作者 Masako Tsurumaru Haruko Takashima Toshiyuki Ikeoka Fumi Mori Satoru Akazawa Ikuko Ueki Masakazu Kobayashi Hironaga Kuwahara Norio Abiru Hironori Yamasaki Atsushi Kawakami 《World Journal of Diabetes》 SCIE CAS 2013年第5期227-230,共4页
We have previously reported the high levels of glutamic acid decarboxylase 65 autoantibodies(GAD65A)in patients with type 1 diabetes and autoimmune thyroid disease.Here we describe a 32-year-old Japanese female with a... We have previously reported the high levels of glutamic acid decarboxylase 65 autoantibodies(GAD65A)in patients with type 1 diabetes and autoimmune thyroid disease.Here we describe a 32-year-old Japanese female with a thirteen-year history of type 1 diabetes whose levels of GAD65A were elevated just after the emergence of anti-thyroid autoimmunity.At 19 years of age,she developed diabetic ketoacidosis and was diagnosed with type 1 diabetes.She had GAD65A,insulinoma-associated antigen-2 autoantibodies(IA-2A),and zinc transporter-8 autoantibodies(ZnT8A),but was negative for antibodies to thyroid peroxidase(TPOAb)and thyroglobulin(TGAb)at disease onset.ZnT8A and IA-2A turned negative 2-3 years after the onset,whereas GAD65A were persistently positive at lower level(approximately 40 U/mL).However,just after the emergence of TGAb at disease duration of 12.5 years,GAD65A levels were reelevated up to5717 U/mL in the absence of ZnT8A and IA-2A.Her thyroid function was normal and TPOAb were consistently negative.She has a HLA-DRB1*03:01/*04:01-DQB1*02:01/*03:02 genotype.Persistent positivity for GAD65A might be associated with increased risk to develop anti-thyroid autoimmunity. 展开更多
关键词 AUTOIMMUNE THYROID disease Case report glutamic acid DECARBOXYLASE AUTOANTIBODIES Type 1diabetes
下载PDF
Granulocyte colony-stimulating factor increases extracellular glutamic acid uptake and suppresses free radicals in an experimental model of amyotrophic lateral sclerosis 被引量:1
7
作者 Shengzhe Zheng Lei Song Lei Lu Lina Lin Yao Wang Qun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第2期107-111,共5页
Excitatory amino acid toxicity and free radical damage play important roles in amyotrophic lateral sclerosis. Granulocyte colony-stimulating factor (G-CSF) protects nerve cells exposed to high-concentrations of glut... Excitatory amino acid toxicity and free radical damage play important roles in amyotrophic lateral sclerosis. Granulocyte colony-stimulating factor (G-CSF) protects nerve cells exposed to high-concentrations of glutamic acid, suggesting positive effects in the treatment of amyotrophic lateral sclerosis. The present study induced in vitro motor neuron injury using glutamic acid excitotoxicity, and the biochemical effects of G-CSF on glutamic acid concentration were determined. In addition, the effects of G-CSF on superoxide dismutase, glutathione peroxidase activity in motor neurons, and malondialdehyde and nitric oxide contents were analyzed. Immunohistochemistry was performed to measure neuronal survival. Results revealed that G-CSF significantly suppressed free radical activity, inhibited excitotoxicity, and reduced apoptosis and loss of motor neurons in the anterior horn of the spinal cord. 展开更多
关键词 amyotrophic lateral sclerosis glutamic acid granulocyte colony-stimulating factor oxygen free radical neural regeneration
下载PDF
Analysis of Glutamic Acid in Cerebrospinal Fluid by Capillary Electrophoresis with High Frequency Conductivity Detection 被引量:1
8
作者 HalYunZHAI JunMeiWANG +3 位作者 XiaoLiYAO XueCaiTAN PeiXiangCAI ZuanGuangCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第2期225-228,共4页
A rapid method to determine glutamic acid (Glu) in cerebrospinal fluid (CSF) by capillaryelectrophoresis with high frequency conductivity detection (contactless conductivity detection) wasdescribed. The CSF sample was... A rapid method to determine glutamic acid (Glu) in cerebrospinal fluid (CSF) by capillaryelectrophoresis with high frequency conductivity detection (contactless conductivity detection) wasdescribed. The CSF sample was pretreated with silver cation resin to remove high concentration ofCl- ions in CSF. The separation was achieved in the buffer solution of 10 mmol/L Tris and 8mmol/L boric acid at the separation voltage of 20.0 kV. Glu showed linear response in the range of5.0×10-6 to 6.0×10-3 mol/L, the limit of detection was 1.0×10-6 mol/L. The method was used foranalysis Glu in CSF satisfactorily with a recovery of 97.8-98.8%. 展开更多
关键词 Capillary electrophoresis high frequency conductivity detection contactless conducti-vity detection glutamic acid cerebrospinal fluid.
下载PDF
Repeat Whole Blood Donation Correlates Significantly with Reductions in BMI and Lipid Profiles and Increased Gamma Glutamic Transferase (GGT) Activity among Nigerian Blood Donors 被引量:1
9
作者 Teddy C. Adias Anastecia Chika Igwilo Zaccheaus Awortu Jeremiah 《Open Journal of Blood Diseases》 2012年第4期90-94,共5页
Background: The effect of repeated blood donation on some biochemical values of healthy adult male blood donors in Calabar, Nigeria was studied. Methods: One hundred and fifty three (153) healthy repeat blood donors a... Background: The effect of repeated blood donation on some biochemical values of healthy adult male blood donors in Calabar, Nigeria was studied. Methods: One hundred and fifty three (153) healthy repeat blood donors and 90 first time blood donors constituted the study population. Samples were analyzed using colorimetric procedures. Results: The BMI values of 24.4 ± 2.4 kg/ m2 in the first time donors was significantly higher than the 21.7 ± 1.7 kg/m2 obtained in repeat donors (P 2 = 0.7934, P Conclusion: A reduction in the values of some lipid profiles and high GGT activity is associated with repeated blood donations in this study population. Repeated blood donation may play a significant role in reducing the incidence of heart disease. 展开更多
关键词 Blood DONATION GAMMA glutamic TRANSFERASE Body Mass Index Lipid Profiles
下载PDF
Study on the Dissolution of Dusts in Glutamic Acid
10
作者 ZHANG Ling DONG Faqin HE Xiaochun 《矿物学报》 CAS CSCD 北大核心 2013年第S1期136-136,共1页
This article describes the characteristics of natural dusts, artificial dusts and industrial dusts, such as mineral phases, chemical components, morphological observation and size. Quartz and calcite are the main phas... This article describes the characteristics of natural dusts, artificial dusts and industrial dusts, such as mineral phases, chemical components, morphological observation and size. Quartz and calcite are the main phases of natural dusts and industrial dusts with high SiO2, CaO and low K2O, Na2O on the chemical composition. Natural dusts are mainly irregular shaped and some particle aggregation made of small dusts on the surface of large dust. Industrial dusts are globular and blob-like, but artificial dusts are columnar and fibrous. The fine particles are mainly in the range of 0.3-5 μm,of which the dusts of less than 5 μm are over 99%.The dissolution and electrochemical action of dusts in glutamic acid liquor at the simulated human body temperature (37 ℃) in 32 hours were investigated. The changes of pH values and electric conductivity of those dusts were similar, increased slowly in first 8 hours, and then the pH values increased rapidly. The total amount of dissolved ions of K, Ca, Na, Mg was 35.4-429 mg/L, particularly Ca was maximal of 20-334 mg/L. The total amount of dissolved ions of Fe, Zn, Mn, Pb, Ba was 0.18-5.59 ppm and the Al, Si was 3.0-21.7 mg/L. Each element dissolved rapidly relatively in first 16 hours. The relative solubility order of dusts in glutamic acid are: wollastonite > serpentine > sepiolite, the cement plant industrial dusts > power plant industrial dusts, and natural dusts have similar solubility. The wollastonite and power plant industrial dusts have highest solubility, which have high content of CaO; this shows there are a poorer corrosion-resisting ability and lower bio-resistibility. Sepiolite and cement plant industrial dusts have lowest solubility, which have high content of SiO2; this shows there are a higher corrosion-resisting ability and stronger bio-resistibility. 展开更多
关键词 DUST glutamic ACID CHARACTERISTIC analysis ELECTROCHEMISTRY characteristics DISSOLUTION
下载PDF
In Vitro Biomineralization of Glutaraldehyde Crosslinked Chitosan/Glutamic Acid Films
11
作者 冯芳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第1期9-14,共6页
In vitro biomineralization of glutaraldehyde crosslinked chitosan/glutamic acid films were studied. IR and ESCA (electron spectroscopy for chemical analysis) determinations confirm that chitosan and glutamic acid ar... In vitro biomineralization of glutaraldehyde crosslinked chitosan/glutamic acid films were studied. IR and ESCA (electron spectroscopy for chemical analysis) determinations confirm that chitosan and glutamic acid are successfully crosslinked by glutaraldehyde to form chitosan-glutamic acid surfaces. Composite films were soaked in saturated Ca(OH)2 solution for 8 d and then immersed in simulated body fluid (SBF) for more than 20 d. Morphological characterizations and structure of cal-cium phosphate coatings deposited on the films were studied by SEM, XRD, and EDAX (energy dispersive X-ray analysis). Initially, the treatment in SBF results in the formation of single-layer cal-cium phosphate particles over the film surface. As immersion time increases, further nucleation and growth produce the simulated calcium-carbonate hydroxyapatite coating. ICP results show Ca/P ratio of calcium phosphate coating is a function of SBF immersion time. The inducing of glutamic acid improves the biomineralization property of chitosan films. 展开更多
关键词 CHITOSAN BIOMINERALIZATION calcium phosphate glutamic acid
下载PDF
Tb(lll) and Ca(ll) Ion Equilibria in the Presence of Glutamic Acid and Glutamine
12
作者 Chun Ji NIU Shu Fu ZHAO +4 位作者 Yue Ting MA Hui ZHAO Yan Min LIU Shu Gong ZHANG Jia Zuan NI(Laboratory of Rare Earth Chemistry and Physics. Changchun Institute of Applied Chemistry, Academia Sinica, Changchun 130022) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期641-642,共2页
Tb(111) and Ca(11) ion equilibria in the presence of glutamic acid and glutamine were studied by potentiometric titration at 37'C and an ionic strength of 0. 15mol/L(NaCl) .The stability constants for Tb(111) and ... Tb(111) and Ca(11) ion equilibria in the presence of glutamic acid and glutamine were studied by potentiometric titration at 37'C and an ionic strength of 0. 15mol/L(NaCl) .The stability constants for Tb(111) and Ca(11)complexes in the systems were obtained. The species and their distribution in the systems were discussed. 展开更多
关键词 Ion Equilibria in the Presence of glutamic Acid and Glutamine TB lll and Ca
下载PDF
Determination of Enantiomeric Excess of Glutamic Acids by Lab-made Capillary Array Electrophoresis
13
作者 Jun WANG Kai Ying LIU Li WANG Ji Ling BAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第1期49-52,共4页
Simulated enantiomeric excess of glutamic acid was determined by a lab-made sixteen-channel capillary array electrophoresis with confocal fluorescent rotary scanner. The experimental results indicated that the capilla... Simulated enantiomeric excess of glutamic acid was determined by a lab-made sixteen-channel capillary array electrophoresis with confocal fluorescent rotary scanner. The experimental results indicated that the capillary array electrophoresis method can accurately determine the enanfiomefic excess of glutamic acid and can be used for high-throughput screening system for combinatorial asymmetric catalysis. 展开更多
关键词 Capillary array electrophoresis enantiomeric excess glutamic acid.
下载PDF
Double Labeling Immulloelectron Microscopic Study on the Synaptic Connections between Glutamic Acid Neurons and GABA Neurons in the Hippocampus of Rats
14
作者 朱长庚 蔡秋云 +1 位作者 刘庆莹 魏瑛 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2000年第1期1-5,共5页
Summary: In order to explore the roles of different neurotransmitters in epileptic pathogenesis, the synaptic connections between glutamic acid (Gin) neurons and GABA neurons in normal rat hippocampus were studied by ... Summary: In order to explore the roles of different neurotransmitters in epileptic pathogenesis, the synaptic connections between glutamic acid (Gin) neurons and GABA neurons in normal rat hippocampus were studied by pre-embedding double labeling immunoelectron microscopy. The GABA immunoreaction was first demonstrated by chromogen DAB, then the Gin immunoreaction was demonstrated by molybdic acid-TAB method. After being stabilized by DAB-cobalt chloride. the sections were processed for electron microscopic embedding. Under electron microscope, there were many Gin immunoreaction-positive neurons in the pyramidal layer of hippocampal CA1 area and some GABA immunoreaction-positive neurons with pyramidal or polygonal perikarya in the pyramidal, polymorphic and radiant layer of CA1 area. There were also symmetric dendro-axonic synapses formed by GABA-positive dendrites and Glu-positive a-cons in the polymorphic layer and symmetric axo-dendritic synapses formed by GABA-positive axons and Glu-positive dendrites in the radiant layer. In addition, there were symmetric autoregulatory axo-dendritic synapses be- tween Gin-positive axons and dendrites and autoregulatory axo-axonic synapses (both symmetric and asymmetric) between GABA-positive axons. Above mentioned results, for the first time, showed that there were complex synaptic regulatory relationships between excitatory Glu neurons and inhibitory GABA neurons in the hippocampal CA1 area, thereby, providing ultrastructural evidence for different neurotransmitters participating in epileptic pathogenesis. 展开更多
关键词 HIPPOCAMPUS glutamic acid gama-aminobutyric acid SYNAPSE immunoelectron microscopy
下载PDF
Preparation and Characterization of Orally Fast-Disintegrating Mini-Tablets Containing Diphenhydramine Hydrochloride and Aspartic or Glutamic Acid as an Umami Amino Acid
15
作者 Kyoko Ohkawa Haruka Nishikawa +4 位作者 Honami Kojima Takayoshi Okuno Rio Uno Miyako Yoshida Takahiro Uchida 《Pharmacology & Pharmacy》 2021年第12期283-292,共10页
The aim of this study was to prepare diphenhydramine hydrochloride (DPH)-loaded orally fast-disintegrating mini-tablets (OFDMTs) containing either L-aspartic acid (Asp) or L-glutamic acid (Glu) as bitterness-suppressa... The aim of this study was to prepare diphenhydramine hydrochloride (DPH)-loaded orally fast-disintegrating mini-tablets (OFDMTs) containing either L-aspartic acid (Asp) or L-glutamic acid (Glu) as bitterness-suppressant, to characterize the prepared tablets and to evaluate their bitterness under conditions mimicking those of the oral cavity. The preparation of five formulation batches of the OFDMTs involved mixing DPH, with or without two different concentrations of Asp or Glu, and a premix containing a disintegrating agent. When all ingredients were well mixed, the mixture was directly compacted to form small (4 mm diameter) DPH-loaded OFDMTs. There were only small differences between the tablets with respect to mass, diameter, width and hardness. The disintegration times of the five formulation batches of DPH-loaded OFDMTs were measured using the OD-mate, a disintegration test apparatus in which conditions resemble those of the oral cavity. The disintegration times were all within 10 s of exposure to a medium representing the inside of the oral cavity. Rapid release profiles were observed for DPH, Asp and Glu in these dissolution tests. The taste sensor outputs of samples taken at different times (5 - 30 s) from the dissolution test solutions of the four DPH-loaded OFDMTs containing Asp or Glu were significantly inhibited compared with those of control DPH-loaded OFDMT. These results suggest that the inclusion of Asp or Glu in DPH-loaded OFDMTs is sufficient to mask bitterness in the oral cavity for the first 30 s after the tablet is placed in the mouth. It is anticipated that swallowing will have taken place within 30 s. 展开更多
关键词 Orally Fast Disintegrating Mini-Tablets DIPHENHYDRAMINE Aspartic Acid glutamic Acid OD-Mate
下载PDF
SYNTHESIS AND CATALYTIC PROPERTY OF POLYSTYRENE SUPPORTED GLUTAMIC ACID SCHIFF BASE COMPLEX OF Mn(Ⅱ) IN AEROBIC OXIDATION OF CYCLOHEXENE
16
作者 CHEN Songtao ZHAO Ganqing +1 位作者 LU Xiaoqing XIE Jimin 《Chinese Journal of Reactive Polymers》 2007年第1期112-118,共7页
The polystyrene supported glutamic acid Schiff base complex of Mn ( Ⅱ ) (PS-Sal-Glue-Mn) was prepared with chloromethylated styrene polymer beads, 2,4-dihydroxybenzaldehyde, L-glutamic acid and manganese ( Ⅱ )... The polystyrene supported glutamic acid Schiff base complex of Mn ( Ⅱ ) (PS-Sal-Glue-Mn) was prepared with chloromethylated styrene polymer beads, 2,4-dihydroxybenzaldehyde, L-glutamic acid and manganese ( Ⅱ ) acetate tetrahyrate. The polymeric ligand and the complex were characterized by FT-IR, small area X-ray photoelectron spectroscopy (XPS) and 1CP-AES. In the presence of the manganese complex, cyclohexene (1) was effectively oxidized by molecular oxygen without reductant. The major products of the reaction were 2-cyclohexen-l-ol (2), 2-cyclohexen-l-one (3) and 2-cyclohexen-1- hydroperoxide (4), which was different with typical oxidation of cyclohexene. The influence of reaction temperature and additive for oxidation had been studied. The selectivity of 2-cyclohexen-1-hydroperoxide varied with reaction time and different additives. The mechanism of cyclohexene oxidation had also been discussed. 展开更多
关键词 Aerobic oxidation Polystyrene supported manganese complex CYCLOHEXENE glutamic acid.
下载PDF
Effects of Glutamic Acid on C-type Inactivation of Kv1.4ΔN Channel
17
作者 叶琤 李晓艳 +1 位作者 舒周伍 蒋学俊 《South China Journal of Cardiology》 CAS 2008年第1期39-43,共5页
Objectives Acidosis has an inhibitory effect on the inactivation of Kv1.4 ΔN channel through the position H508. So in order to show the effects of glutamic acid on the mutant Kv 1.4 channel that lacks N-type inactiva... Objectives Acidosis has an inhibitory effect on the inactivation of Kv1.4 ΔN channel through the position H508. So in order to show the effects of glutamic acid on the mutant Kv 1.4 channel that lacks N-type inactivation (Kv1.4 Δ2-146), we studied in the expression system of the Xenopus oocytes. Methods The two-electrode voltage-clamp technique (TEV) was used to record the currents. Results Acidosis increased fKv1.4 Δ2-146 C-type inactivation. After application of glutamic acid (1 mmol/L) to Kv1.4 Δ2-146 increased C-type inactivation further, changed inactivation time constants from (2.02 ± 0.39 s ) to (1.71 ± 0.23 s) (P〈 0.05) at +50mv, and shifted the steady-state inactivation curves of Kv1.4 ΔN to positive potential, which was from (-44.30 ± 0.59 mV) to (-39.88 ± 0.29 mV)(P〈0.05). and slowed the rate of recovery from inactivation, which was from (1.64 ± 0.19 s) to (1.91 ± 0.23 s)(P〈 0.05). Conclusions Together, these results suggest that 1 mmol/L glutamic acid accelerates the C-type inactivation of Kv1.4 ΔN in pH 6.8. 展开更多
关键词 glutamic acid Kv1.4ΔN C-type inactivation xenopus oocytes
下载PDF
STUDY ON THE SEPARATION OF GLUTAMIC ACID BY ION-EXCHANGE
18
作者 Shen Jinyu Wang Qinyu 《Chinese Journal of Reactive Polymers》 1995年第1期45-52,共8页
The feasibility of recavering glutamic acid by ion exchange method with macroporous resins was investigated. Their adsorption properties in static state and the effective factors,such as pH, concentration of feed and ... The feasibility of recavering glutamic acid by ion exchange method with macroporous resins was investigated. Their adsorption properties in static state and the effective factors,such as pH, concentration of feed and the ratio of ammonium ion toglutamic acid,were systematically explored. The best conditions of separating glutamic acid from mother liquid were obtained. 展开更多
关键词 glutamic Acid Ion - exchange SEPARATION
下载PDF
3-35 Influence of the Initial pH on Glutamic Acid Fermentation
19
作者 Miao Jianshun Cao Guozhen +2 位作者 Lu Dong Zhang Miaomiao Li Wenjian 《IMP & HIRFL Annual Report》 2014年第1期128-128,共1页
An important factor of the physical and chemical properties of solution, pH is the index of hydrogen ionconcentration in solution. When the pH is higher or lower than the fitness value, the enzyme activity of bacteria... An important factor of the physical and chemical properties of solution, pH is the index of hydrogen ionconcentration in solution. When the pH is higher or lower than the fitness value, the enzyme activity of bacteriagrowth and metabolism will decrease, and the metabolism of cell will be blocked, which could cause arrest of growthand affect the cell membrane potential, then the biological function of cell membrane would be changed, and also,the material in and out of cell would be influenced. When the pH of fermented liquid is lower in the produceacid fermentation period, the activity of glutamate dehydrogenase will reduce, and the metabolism of substanceand energy will be in the direction of acetyl glutamine synthesis, which could cause the decline of glutamic acidproductivity. 展开更多
关键词 INFLUENCE INITIAL glutamic
下载PDF
RAPID DETERMINATION OF L-GLUTAMIC ACID WITH AN ENZYME REACTOR OF L-GLUTAMIC DECARBOXYLASE IMMOBILIZED ON ION EXCHANGE RESIN
20
作者 WUGuoqi LING Daren +1 位作者 WANG Fan SONG Guoqiang 《Chinese Journal of Reactive Polymers》 2001年第2期160-167,共8页
The preparation and characterization of an immobilized L-glutamic decarboxylase (GDC) were studied. This work is to develop a sensitive method for the determination of L-glutamate using a new biosensor, which consists... The preparation and characterization of an immobilized L-glutamic decarboxylase (GDC) were studied. This work is to develop a sensitive method for the determination of L-glutamate using a new biosensor, which consists of an enzyme column reactor of GDC immobilized on a novel ion exchange resin (carboxymethyl-copolymer of allyl dextran and N.N?methylene-bisacrylamide CM-CADB) and ion analyzer coupled with a CO2 electrode. The conditions for the enzyme immobilization were optimized by the parameters: buffer composition and concentration, adsorption equilibration time, amount of enzyme, temperature, ionic strength and pH. The properties of the immobilized enzyme on CM-CADB were studied by investigating the initial rate of the enzyme reaction, the effect of various parameters on the immobilized GDC activity and its stability. An immobilized GDC enzyme column reactor matched with a flow injection system-ion analyzer coupled with CO2 electrode-data collection system made up the original form of the apparatus of biosensor for determining of L-glutamate acid. The limit of detection is 1.0×10-5 M. The linearity response is in the range of 5×10 -2-5×10 -5 M . The equation of linear regression of the calibration curve is y= 43.3x + 181.6 (y is the milli-volt of electrical potential response, x is the logarithm of the concentration of the substrate of L-glutamate acid). The correlation coefficient equals 0.99. The coefficient of variation equals 2.7%. 展开更多
关键词 Immobilized enzyme reactor L-glutamic decarboxylase Glutamate acid Ion exchanger..
下载PDF
上一页 1 2 22 下一页 到第
使用帮助 返回顶部