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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    

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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    

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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    

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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    

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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.    

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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    

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Synthesis and anticancer activity of (+)-nopinone-based 2-amino-3-cyanopyridines

Shengliang LIAO,Shibin SHANG,Minggui SHEN,Xiaoping RAO,Hongyan SI,Jie SONG,Zhanqian SONG

《农业科学与工程前沿（英文）》 2015年 第2卷 第4期   页码 335-340 doi: 10.15302/J-FASE-2015079

摘要： Twelve (+)-nopinone-based 2-amino-3-cyanopyridines 4a–l were synthesized from (–)-β-pinene. The structures of these compounds were characterized by FT-IR, H NMR, and ESI-MS. All the compounds were tested for their anticancer activity against lung cancer cell line A549, gastric cancer cell line MKN45 and breast cancer cell line MCF7 by MTT method, respectively. The results showed that compounds 4f, 4j and 4k had promising anticancer activity against these cancer cell lines, in particular, compound 4f exhibited broad-spectrum and highly efficient anticancer activity against cell lines A549, MKN45 and MCF7 with IC of 23.78, 67.61 and 53.87 µmol·L , respectively. The preliminary analysis of the structure activity relationship implied that the Br or Cl substituted group of the benzene ring in these derivatives significantly contributed to the anticancer activity.

关键词： b-pinene     nopinone     synthesis     2-amino-3-cyanopyridine     anticancer    

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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    

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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    

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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    

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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    

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Insight into the effect of surface carboxyl and amino groups on the adsorption of titanium dioxide for

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    

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Regulatory issues for genetically modified animals

Perry Bradbury HACKETT

《农业科学与工程前沿（英文）》 2020年 第7卷 第2期   页码 188-203 doi: 10.15302/J-FASE-2019307

摘要：

Precision genetics and breeding have the potential to meet the agricultural needs and goals of the world in the 21st century. These needs include increasing the efficiency of production of animals and improving their products with minimal impact on the environment. The USA is the major innovator in genomic science and the acknowledged leader in formulating policies to regulate genetic applications in medicine and agriculture. However, governments worldwide have been exceedingly reluctant to support the introduction of genetically modified (GM) animals into agriculture. Regulatory policies have stagnated due to legal guidelines that could not anticipate the needs and solutions that are evident today. This must change if we are to maintain planetary integrity. I propose a new, market-based regulatory model for GM livestock that has both a strong scientific foundation and has worked for 10000 years. The model is similar to that for information technology in which specific algorithms drive computer and cell phone applications. Genome engineers write genetic algorithms that drive the traits in biological organisms. Accordingly, GM products should be viewed in terms of their use and public benefit rather than by limitations to the genetic programing coming from a few highly vocal groups. Genetic algorithms (Genapps) of the 21st century will include not only introduction of synthetic genes, but also complete natural and synthetic biochemical pathways to produce agricultural products that are maximally efficient, healthy to humans and animals, and sustainable in an era of changing climates while avoiding environmental degradation.

关键词： algorithms     editing     FDA     GMO     recombinant DNA     USDA    

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Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

《能源前沿（英文）》 2012年 第6卷 第2期   页码 138-147 doi: 10.1007/s11708-012-0188-8

摘要： This paper explores the capability of modified differential evolution (MDE) technique for solving the reactive power dispatch (RPD) problem. The proposed method is based on the basic differential evolution (DE) technique with a few modifications made into it. DE is one of the strongest optimization techniques though it suffers from the problem of slow convergence while global minima appear. The proposed modifications are tried to resolve the problem. The RPD problem mainly defines loss minimization with stable voltage profile. To solve the RPD problem, the generator bus voltage, transformer tap setting and shunt capacitor placements are controlled by the MDE approach. In this paper, IEEE 14-bus and IEEE 30-bus systems are chosen for MDE implementation. The applied modification show much improved result in comparison to normal DE technique. Comparative study with other soft-computing technique including DE validates the effectiveness of the proposed method.

关键词： reactive power dispatch (RPD)     modified differential evolution (MDE)     differential evolution algorithm with localizations around the best vector (DELB)    

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Approaching the binding between Cu(II) and aerobic granules by a modified titration and µ-XRF

Hongwei LUO,Longfei WANG,Zhonghua TONG,Hanqing YU,Guoping SHENG

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 362-367 doi: 10.1007/s11783-015-0803-0

摘要： Interactions between metals and activated sludge can substantially affect the fate and transport of heavy metals in wastewater treatment plants. Therefore, it is important to develop a simple, fast and efficient method to elucidate the interaction. In this study, a modified titration method with a dynamic mode was developed to investigate the binding of Cu(II), a typical heavy metal, onto aerobic granules. The titration results indicated that pH and ionic strength both had a positive effect on the biosorption capacity of the granular sludge. The -XRF results demonstrated that the distribution of metals on the granular surface was heterogeneous, and Cu showed strong correlations and had the same “hot spots” positions with other metal ions (e.g., Ca, Mg, Fe etc.). Ion exchange and complexing were the main mechanisms for the biosorption of Cu(II) by aerobic granules. These results would be beneficial for better understanding of Cu(II) migration and its fate in wastewater treatment plants.

关键词： aerobic granules     Cu(II)     modified titration     µ-XRF analysis    

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标题 作者 时间 类型 操作

Immobilization of penicillin G acylase onto amino-modified silica hydrogel

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

期刊论文

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

期刊论文

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

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

Synthesis and anticancer activity of (+)-nopinone-based 2-amino-3-cyanopyridines

Shengliang LIAO,Shibin SHANG,Minggui SHEN,Xiaoping RAO,Hongyan SI,Jie SONG,Zhanqian SONG

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

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

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

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

期刊论文

Insight into the effect of surface carboxyl and amino groups on the adsorption of titanium dioxide for

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

期刊论文

Regulatory issues for genetically modified animals

Perry Bradbury HACKETT

期刊论文

Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

期刊论文

Approaching the binding between Cu(II) and aerobic granules by a modified titration and µ-XRF

Hongwei LUO,Longfei WANG,Zhonghua TONG,Hanqing YU,Guoping SHENG

期刊论文