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Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

《化学科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 465-470 doi: 10.1007/s11705-014-1452-8

摘要: The utilization of poly (2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investigated. Grafted copolymers of 2-hydroxyethylmethacrylate (HEMA) monomers on agar were synthesized by microwave assisted method. drug release studies were performed at pH values of 2 and 7 in order to investigate the possibility of pH triggered release for colon targeted drug delivery. Further, the percent grafting . (the time taken for release of 50% of the enclosed drug) value was studied and the results indicate that it may be possible to develop a programmable drug release matrix based on grafted polysaccharide. Ag-g-P(HEMA) appears to be a useful matrix for controlled release.

关键词: agar     controlled drug release     5-Amino salicylic acid     poly(2-hydroxyethylmethacrylate) grafted agar    

Visualization of amino acid composition differences between processed protein from different animal species

Xingfan ZHOU,Zengling YANG,Longjian CHEN,Lujia HAN

《农业科学与工程前沿(英文)》 2016年 第3卷 第2期   页码 171-179 doi: 10.15302/J-FASE-2016095

摘要: Amino acids are the dominant organic components of processed animal proteins, however there has been limited investigation of differences in their composition between various protein sources. Information on these differences will not only be helpful for their further utilization but also provide fundamental information for developing species-specific identification methods. In this study, self-organizing feature maps (SOFM) were used to visualize amino acid composition of fish meal, and meat and bone meal (MBM) produced from poultry, ruminants and swine. SOFM display the similarities and differences in amino acid composition between protein sources and effectively improve data transparency. Amino acid composition was shown to be useful for distinguishing fish meal from MBM due to their large concentration differences between glycine, lysine and proline. However, the amino acid composition of the three MBMs was quite similar. The SOFM results were consistent with those obtained by analysis of variance and principal component analysis but more straightforward. SOFM was shown to have a robust sample linkage capacity and to be able to act as a powerful means to link different sample for further data mining.

关键词: self-organizing feature maps     visualization     processed animal proteins (PAPs)     amino acid    

Amino acid promoted hydrogen battery system using Mn-pincer complex for reversible CO hydrogenation toformic acid

《能源前沿(英文)》 2022年 第16卷 第5期   页码 697-699 doi: 10.1007/s11708-022-0843-7

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 80-84 doi: 10.1007/s11705-008-0017-0

摘要: 2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature, solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and triethylamine as catalyst, (I) : (II) : (triphenylphosphine) = 1.0 : 1.0 : 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional processes because of its easy handling, high yield and low cost.

关键词: 5-Amino-1     2     4-thiadiazol-3-yl     1     2-dichloroethane     important intermediate     2-benzothiazolyl thioester     temperature    

Insight into the effect of surface carboxyl and amino groups on the adsorption of titanium dioxide foracid red G

Wenlong Zhang, Xuyang Zhao, Lin Zhang, Jinwei Zhu, Shanshan Li, Ping Hu, Jiangtao Feng, Wei Yan

《化学科学与工程前沿(英文)》 2021年 第15卷 第5期   页码 1147-1157 doi: 10.1007/s11705-020-1978-x

摘要: In this study, TiO functionalized with organic groups were prepared to study the effect of carboxyl and amino groups on the adsorption behavior of TiO for the removal of acid red G (ARG) as an anionic dye from aqueous solution. TiO was successfully modified with carboxyl and amino groups by using the hydrolysis method with oxalic acid (OAD, with two carboxyl groups), ethylenediamine (EDA, with two amino groups) and DL-alanine (DLA, with one carboxyl group and one amino group) at low temperature (65 °C) and labeled as OAD-TiO , EDA-TiO and DLA-TiO , respectively. The ARG uptake by the functionalized TiO samples was largely dependent on the functional groups. The interaction between ARG and the functional organic groups on the TiO samples plays an important role in the adsorption process, which leads to the excellent adsorption performance (higher capacity and faster adsorption rate) of the functionalized TiO samples than that of P25 (commercial TiO without modification). Furthermore, there is no obvious loss of the adsorption capacity for the functionalized TiO even after 5 adsorption-desorption cycles, which indicated the good reusability of the modified TiO samples for anionic dye removal from aqueous solution.

关键词: amino group     carboxylic group     titanium dioxide     ARG     adsorption    

Magnetic KIT-6 nano-composite and its amino derivatives as convenient adsorbent for U(VI) sequestration

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2037-2049 doi: 10.1007/s11705-023-2358-0

摘要: Although mesoporous silica with magnetically hybridized two-dimensional channel structures has been well studied in recent years, it remains a challenge to fabricate the counterpart with macroporous three-dimensional cubic structures since the highly acidic preparation conditions lead to dissolution of magnetic particles. Herein, we successfully prepared magnetic KIT-6 nano-composite and its amino derivatives by bearing acid-resistant iron oxide. The prepared materials exhibited excellent properties for U(VI) ions removal from aqueous solutions under various conditions. The experimental data show that the U(VI) adsorption features fast adsorption kinetics, high adsorption capacity and ideal selectivity toward U(VI). The adsorption process is of spontaneous and endothermic nature and ionic strength independence, and the adsorbents can be easily regenerated by acid treatment. Compared to pristine KIT-6, the introduction of magnetism does not reduce the efficiency of the material to remove U(VI) while exerting its role as a recovery adsorbent. The findings of this work further demonstrate the potential broad application prospects of magnetic hybrid mesoporous silica in radionuclide chelation.

关键词: magnetic nanoparticle     3D mesoporous silica     amino functionalization     adsorption of U(VI)     acid resistance    

Evolution of humic substances in polymerization of polyphenol and amino acid based on non-destructive

Jianmei Zou, Jianzhi Huang, Huichun Zhang, Dongbei Yue

《环境科学与工程前沿(英文)》 2021年 第15卷 第1期 doi: 10.1007/s11783-020-1297-y

摘要: Abstract • Humification evolution was identified with non-destructive characterization method. • Humification process from precursors to fulvic and humic acid was confirmed. • MnO2 alone had limited oxidation ability to form HA. • MnO2 played a key role as a catalyst to transform FA to HA in the presence of O2. • MnO2 could affect the structure of the humification products. Abiotic humification is important in the formation and evolution of organic matter in soil and compost maturing processes. However, the roles of metal oxides in abiotic humification reactions under micro-aerobic remain ambiguous. The aim of this study was to use non-destructive measurement methods to investigate the role of MnO2 in the evolution of humic substances (HSs) during oxidative polymerization of polyphenol-amino acid. Our results suggested a synergistic effect between MnO2 and O2 in promoting the polymerization reaction and identified that MnO2 alone had a limited ability in accelerating the transformation of fulvic acid (FA) to humic acid (HA), whereas O2 was the key factor in the process. Two-dimensional correlation spectroscopy (2D-COS) showed that the evolution in the UV-vis spectra followed the order of 475–525 nm>300–400 nm>240–280 nm in the humification process, indicating the formation of simple organic matter followed by FA and then HA. 13C nuclear magnetic resonance (13C NMR) analysis revealed that the products under both air and N2 conditions in the presence of MnO2 had greater amounts of aromatic-C than in the absence of MnO2, demonstrating that MnO2 affected the structure of the humification products. The results of this study provided new insights into the theory of abiotic humification.

关键词: Two-dimensional correlation spectroscopy (2D-COS)     Humic substances (HSs)     Humification     Manganese dioxide     Polyphenol    

Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 817-829 doi: 10.1007/s11705-022-2254-z

摘要: Amino acids are important nitrogen-containing chemicals that have a variety of applications. Currently, fermentation is the widely employed method to produce amino acids; however, the products are mostly limited to natural amino acids in the L-configuration. Catalytic synthesis is an alternative approach for the synthesis of amino acids with different types and configurations, where the use of renewable biomass-based feedstocks is highly attractive. To date, several lignocellulose and triacylglycerol-derived intermediates, typically α-keto acids and α-hydroxyl acids, have been transformed into amino acids via the amination reaction in the presence of additional nitrogen sources (i.e., NH3·H2O). Making full use of inherent nitrogen in biomass (i.e., chitin and protein) to produce amino acids avoids the use of extra nitrogen sources and meets the requirements of green chemistry, which is attracting increasing attention. In this review, we summarize different chemical-catalytic systems for the transformation of biomass to amino acids. An outlook on the challenges and opportunities for more effective production of amino acids from biomass by catalytic methods is provided.

关键词: biomass     amino acids     chitin     nitrogen-containing compounds     lignocellulose    

Profiling influences of gene overexpression on heterologous resveratrol production in

Duo Liu,Bingzhi Li,Hong Liu,Xuejiao Guo,Yingjin Yuan

《化学科学与工程前沿(英文)》 2017年 第11卷 第1期   页码 117-125 doi: 10.1007/s11705-016-1601-3

摘要: Metabolic engineering of heterologous resveratrol production in faces challenges as the precursor L-tyrosine is stringently regulated by a complex biosynthetic system. We overexpressed the main gene targets in the upstream pathways to investigate their influences on the downstream resveratrol production. Single-gene overexpression and DNA assembly-directed multigene overexpression affect the production of resveratrol as well as its precursor -coumaric acid. Finally, the collaboration of selected gene targets leads to an optimal resveratrol production of 66.14±3.74 mg·L , 2.27 times higher than the initial production in YPD medium (4% glucose). The newly discovered gene targets expressing phosphoribosylanthranilate isomerase, expressing 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase, and expressing 4-coumaryl-CoA ligase show notable positive impacts on resveratrol production in .

关键词: resveratrol     aromatic amino acid     DNA assembly     metabolic engineering     gene overexpression    

新型通用离子交换膜的研究与实践

汪耀明,吴亮,徐铜文

《中国工程科学》 2014年 第16卷 第12期   页码 76-86

摘要:

基于离子交换膜的电膜技术,由于其独特的离子传递特性,可以进行离子物系的分离分级,在清洁生产、节能减排、环境保护、能量转换等方面有着广泛的应用前景。然而,目前国内相关均相离子膜产品尚处于起步阶段,以日本为首的国家对我国进行相关技术封锁和价格垄断。正是基于这样的产业背景和现实意义,开发出新型的均相离子膜制备路线尤为重要。本课题组提出了一种简单而通用的侧链型离子化芳香族聚合物的合成方法,即“离子单体聚酰基化”均相离子交换膜制备路线,并通过ATRP法来设计离子交换膜的主链憎水、侧链亲水的接枝结构,通过对接枝密度和接枝长度进行调节,实现对膜性能的调控,以满足不同的应用过程对膜性能的要求。此种均相离子交换膜的制备工艺及产业化生产攻关,可以打破以日本为首的国家对我国离子膜产品的技术封锁,实现具有我国自主知识产权的离子膜技术的产业化。制备条件温和、制备工艺简单、快捷,而且整个过程没有传统方法中常用的季铵化或磺化步骤,有效地简化工艺和降低环境污染,可用于扩散渗析、普通电渗析以及双极膜电渗析过程对高性能离子交换膜材料的需求。该系列离子交换膜在特种废水处理、有机酸生产、氨基酸分离纯化、重金属废水处理等诸多领域得到了广泛的使用,均取得了较为满意的使用效果。

关键词: 离子交换膜     电渗析     有机酸     氨基酸     重金属废水    

Insights into the changes of amino acids, microbial community, and enzymatic activities related with

《环境科学与工程前沿(英文)》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1635-y

摘要:

● The highest seed germination index was achieved at 0.3 g/g total solids of food waste.

关键词: Composting     Food waste     Amino acids     Microbial community     Enzymatic activity     Nutrient quality    

Immobilization of penicillin G acylase onto amino-modified silica hydrogel

Weibing Dong, Huining HE, Junbo Gong, Victor C. YANG,

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 87-90 doi: 10.1007/s11705-009-0298-y

摘要: Amino-modified silica hydrogel (N-MSHG) was prepared by a simple sol-gel processing via the co-condensation of commercial silica sol with 3-aminopropyltrie-oxysilane. Penicillin G acylase (PGA), a model enzyme, was covalently immobilized onto the N-MSHG and then was used for the enzymatic synthesis of amoxicillin. The samples were characterized by Nitrogen sorption analysis, FT-IR and thermal gravimetric analysis (TGA). The results showed that the amino-modified gel was a mesoporous material with an average pore size of 12.64±0.17nm. The immobilization process was efficient and the immobilized enzyme showed high catalytic efficiency. The yield of the synthesis of amoxicillin in aqueous media was 38% for 2.5h. This sol-gel preparation is simple and shows prominent potential value in industrial processing.

关键词: gravimetric     amino-modified     efficient     Amino-modified     amoxicillin    

Insulin resistance and the metabolism of branched-chain amino acids

null

《医学前沿(英文)》 2013年 第7卷 第1期   页码 53-59 doi: 10.1007/s11684-013-0255-5

摘要:

Insulin resistance (IR) is a key pathological feature of metabolic syndrome and subsequently causes serious health problems with an increased risk of several common metabolic disorders. IR related metabolic disturbance is not restricted to carbohydrates but impacts global metabolic network. Branched-chain amino acids (BCAAs), namely valine, leucine and isoleucine, are among the nine essential amino acids, accounting for 35% of the essential amino acids in muscle proteins and 40% of the preformed amino acids required by mammals. The BCAAs are particularly responsive to the inhibitory insulin action on amino acid release by skeletal muscle and their metabolism is profoundly altered in insulin resistant conditions and/or insulin deficiency. Although increased circulating BCAA concentration in insulin resistant conditions has been noted for many years and BCAAs have been reported to be involved in the regulation of glucose homeostasis and body weight, it is only recently that BCAAs are found to be closely associated with IR. This review will focus on the recent findings on BCAAs from both epidemic and mechanistic studies.

关键词: branched-chain amino acids     leucine     isoleucine     valine     insulin resistance    

Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1458-7

摘要:

•Tryptophan protein, and aromatic protein I/II were the key identified proteins.

关键词: Sludge pretreatments     Dissolved organic nitrogen     Proteins     Amino acids     Structural equation model     Metagenomic sequencing analysis.    

Continuous amino-functionalized University of Oslo 66 membranes as efficacious polysulfide barriers for

《化学科学与工程前沿(英文)》 2023年 第17卷 第2期   页码 194-205 doi: 10.1007/s11705-022-2206-7

摘要: The shuttle effect of soluble polysulfides is a serious problem impeding the development of lithium−sulfur batteries. Herein, continuous amino-functionalized University of Oslo 66 membranes supported on carbon nanotube films are proposed as ion-permselective interlayers that overcome these issues and show outstanding suppression of the polysulfide shuttle effect. The proposed membrane material has appropriately sized pores, and can act as ionic sieves and serve as barriers to polysulfides transport while allowing the passage of lithium ions during electrochemical cycles, thereby validly preventing the shuttling of polysulfides. Moreover, a fast catalytic conversion of polysulfides is also achieved with the as-developed interlayer. Therefore, lithium−sulfur batteries with this interlayer show a desirable initial capacity of 999.21 mAh·g–1 at 1 C and a durable cyclic stability with a decay rate of only 0.04% per cycle over 300 cycles. Moreover, a high area capacity of 4.82 mAh·cm–2 is also obtained even under increased sulfur loading (5.12 mg·cm–2) and a lean-electrolyte condition (E/S = 4.8 μL·mg–1).

关键词: lithium−sulfur batteries     amino-functionalized University of Oslo 66 membrane     polysulfide     interlayer    

标题 作者 时间 类型 操作

Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

期刊论文

Visualization of amino acid composition differences between processed protein from different animal species

Xingfan ZHOU,Zengling YANG,Longjian CHEN,Lujia HAN

期刊论文

Amino acid promoted hydrogen battery system using Mn-pincer complex for reversible CO hydrogenation toformic acid

期刊论文

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

期刊论文

Insight into the effect of surface carboxyl and amino groups on the adsorption of titanium dioxide foracid red G

Wenlong Zhang, Xuyang Zhao, Lin Zhang, Jinwei Zhu, Shanshan Li, Ping Hu, Jiangtao Feng, Wei Yan

期刊论文

Magnetic KIT-6 nano-composite and its amino derivatives as convenient adsorbent for U(VI) sequestration

期刊论文

Evolution of humic substances in polymerization of polyphenol and amino acid based on non-destructive

Jianmei Zou, Jianzhi Huang, Huichun Zhang, Dongbei Yue

期刊论文

Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

期刊论文

Profiling influences of gene overexpression on heterologous resveratrol production in

Duo Liu,Bingzhi Li,Hong Liu,Xuejiao Guo,Yingjin Yuan

期刊论文

新型通用离子交换膜的研究与实践

汪耀明,吴亮,徐铜文

期刊论文

Insights into the changes of amino acids, microbial community, and enzymatic activities related with

期刊论文

Immobilization of penicillin G acylase onto amino-modified silica hydrogel

Weibing Dong, Huining HE, Junbo Gong, Victor C. YANG,

期刊论文

Insulin resistance and the metabolism of branched-chain amino acids

null

期刊论文

Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

期刊论文

Continuous amino-functionalized University of Oslo 66 membranes as efficacious polysulfide barriers for

期刊论文