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Chemical Research in Chinese Universities 2018年第1期34卷 101-106页

作者： LU Wenjie XU Rongjin ZHANG Xinai SHEN Jianzhong LI Changfeng School of Energy and Power Engineering Jiangsu University Zhenjiang 212013 P. R. China School of Food and Biological Engineering Jiangsu University Zhenjiang 212013 R R. China

An electrochemical immunosensor was developed for sensitive assay ofE. coli in urban sludge, in which electron mediator-mediated enzymatic catalysis and gold nanoparticles（AuNPs） were utilized for signal amplification. The immnuosensing platform chitosan-thionine（chit-thio）/poly（amidoamine） dendrimer-encapsulated AuNPs [PAMAM（Au）] composites were first prepared from chit-thio and PAMAM（Au） using the layer-by-layer method to provide a matrix for high-stability and high-bioactivity bindings of the capture antibody（cAb）. Moreover, the {dAb-AuNPs-HRP} nanoprobes were designed to exploit the amplification effect of the carrier AuNPs due to the loading amounts of horseradish peroxidase（HRP）and the detection antibody（dAb）. The sandwich-type immunoassay was then successfully used to assay E. coli based on the oxidation of thionine as a result of H2O2-induced enzymatic catalytic reaction by HRP. This study presents a powerful tool in electrochemical immunoassay for E. coli detection with rapid response, high-sensitivity and high-specificity, providing a potential new tool for feasibility assessment of sludge recycle.

关键词： Electron mediator enzymatic catalysis Electrochemical immtmosensor E. coli Urban sludge

Biodiesel Production from Waste Cooking Oil by enzymatic catalysis Process

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Journal of Chemistry and Chemical Engineering 2013年第10期7卷 993-1000页

作者： Ignacio Contreras Andrade Fabio Emiro Sierra Vargas Carlos Alberto Guerrero Fajardo Department of Biology and Chemistry University of Sinaloa Culiacan 80007 Mexico Department of Chemistry National University of Colombia Bogota 11001 Colombia

Biodiesel is an excellent option for reducing dependence on fossil fuels with environmental advantages by reducing hazardous emissions. The enzymatic transesterification has attracted the attention of researchers in the last decade and the advantages of enzymatic catalysis show that the production of biodiesel by this route has good potential, mainly because it is friendly environment. For biodiesel, production process by enzyme catalysis is chosen the response surface methodology. It is an experimental strategy to find the best operating conditions oftransesterification reaction to improve the biodiesel quality. The Process has three variables： temperature, molar ratio oil-alcohol and catalyst quantity. The process was monitored by GC-FID （gas chromatography with flame ionization detector）. The yield of the transesterification reaction by enzymatic catalysis decreases with increasing temperature, and may be due to inactivation of the enzyme by denaturation at temperatures above 50 ℃. The second-order design used was the ＂CDC （central design composition）＂ which produced a maximum yield of 95.5% in the transesterification reaction by enzymatic catalysis obtained at a temperature of 45 ℃, molar ratio methanol：oil of 8：1 and a catalyst loading of 8% wt.

关键词： Biodiesel waste cooking oil transesterification reaction enzymatic catalysis biofuel

Advances in Application of Non-aqueous Phase enzymatic catalysis in Food Additive Production

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Agricultural Science & Technology 2013年第1期14卷 169-175页

作者：余泗莲余琳余彬孙文敬刘长峰杨梦依崔凤杰百勤异VC钠有限公司江西德兴334221 江苏大学食品与生物工程学院江苏镇江212013

Non-aqueous phase enzymatic catalysis technology has been widely ap- plied in the area of food additives production. This paper reviewed the types of re- action medium of non-aqueous phase enzymatic catalysis reaction, introduced the application of non-aqueous phase enzymatic catalysis technology in catalysis of L-ascorbic （isoascorbic） acid esters, short-chain acid esters, sugar esters, vitamin A esters, vi- tamin E esters, and other food additives, and finally predicted the prospects of non- aqueous phase enzymatic catalysis technology.

关键词： Non-aqueous phase enzymatic catalysis Food additives Ester synthesis

Enzyme-instructed hybrid nanogel/nanofiber oligopeptide hydrogel for localized protein delivery

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Acta Pharmaceutica Sinica B 2021年第7期11卷 2070-2079页

作者： Tianyue Jiang Yudi Ma Xiao Xu Qingchun Ji Mingxing Feng Cheng Cheng Yang Feng Bingfang He Ran Mo School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 211816China State Key Laboratory of Natural Medicines Jiangsu Key Laboratory of Drug Discovery for Metabolic DiseasesCenter of Advanced Pharmaceuticals and BiomaterialsChina Pharmaceutical UniversityNanjing 210009China

Enzyme-catalysis self-assembled oligopeptide hydrogel holds great interest in drug delivery,which has merits of biocompatibility,biodegradability and mild gelation ***,its application for protein delivery is greatly limited by inevitable degradation of enzyme on the encapsulated proteins leading to loss of protein ***,for the intracellularly acted proteins,cell membrane as a primary barrier hinders the transmembrane delivery of *** internalized proteins also suffer from acidic and enzymatic degradation in endosomes and *** herein develop a proteasemanipulated hybrid nanogel/nanofiber hydrogel for localized delivery of intracellularly acted *** embedded polymeric nanogels(CytoC/aNGs)preserve activity of cytochrome c(CytoC)that is an intracellular activator for cell apoptosis as a model protein against proteolysis,and do not affect the gelation properties of the protease-catalysis assembled *** injectable hydrogel(CytoC/aNGs/Gel)serves as a reservoir to enhance intratumoral retention and realize sustainable release of CytoC/*** released CytoC/aNGs increase cellular uptake of CytoC and enhance its intracellular delivery to its target site,cytoplasm,resulting in favorable apoptosis-inducing and cytotoxic *** show that a single local administration of CytoC/aNGs/Gel efficiently inhibit the tumor growth in the breast tumor mouse model.

关键词： Protein delivery Oligopeptide hydrogel Nanogel enzymatic catalysis Cytochrome c Apoptosis Local administration Cancer therapy

Open Tubular Microreactor with Enzyme Functionalized Micro- fluidic Channel for Amperometric Detection of Glucose

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Chinese Journal of Chemistry 2012年第9期30卷 2145-2150页

作者：张蕾曲平盛金雷建平鞠烷先 State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210093China

A simple and efficient method using enzyme immobilized microfluidic channel as open tubular microreactor was designed for amperometric detection of glucose. The microreactor was composed of a polydimethylsilicone/ glass hybrid device with three reservoirs, a cooling cave and a 6 cm capillary with a sampling fracture as micro-channel. The microchannel was further modified by thermal polymerization, followed by covalently attaching with glucose oxidase. Through fracture sampling and electrochromatography separation, the production via enzymatic reaction was determinated by Pt electrode at the end of capillary. The linear range for the detection of glucose was 0.05--7.5 mmol·L-1 with detection limit of 23μmol.L-1 The inter-and intra-chip reproducibilities for determination of 2.5 mmol-L-1 glucose were 98.5% （n=5） and 96.0% （n=5）, respectively. With the advantage of flexible assembly, rapid efficiency, good stability and low-cost, this microreactor provided a potential platform for estab- lishing a portable enzyme-based chemical detection system in practical application.

关键词： microreactor amperometric detection glucose enzymatic catalysis microfluidic channel

Molecular characterization and structure basis of a malonyltransferase with both substrate promiscuity and catalytic regiospecificity from Cistanche tubulosa

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2333-2348页

作者： Xiao Liu Yuyu Liu Xiping Xu Wenqian Huang Yaru Yan Yingxia Wang Weisheng Tian Ting Mo Xiaoxue Cui Jun Li She-Po Shi Pengfei Tu Modern Research Center for Traditional Chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China Modern Research Center for Traditional Chinese Medicine School of Chinese Materia MedicaBeijing University of Chinese MedicineBeijing 100029China

enzymatic malonylation of natural glycosides provides a promising alternative method for drug-like malonylated glycosides ***,the catalytic potential and structural basis of plant malonyltransferase are far from being fully *** work identified a new malonyltransferase CtMaT1 from Cistanche *** displayed unprecedented mono-and/or di-malonylation activity toward diverse glucosides with different aglycons.A“one-pot”system by CtMaT1 and a malonyl-CoA synthetase was established to biosynthesize nine new malonylated *** investigations revealed that CtMaT1 possesses an adequately spacious acyl-acceptor pocket capable of accommodating diverse ***,it recognizes malonyl-CoA through strong electrotactic and hydrogen ***/MM calculation revealed the H167-mediated SN2 reaction mechanism of CtMaT1,while dynamic simulations detected the formation of stable hydrogen bonds between the glucose-6-OH group and H167,resulting in its high malonylation *** energy profiles of two isomeric glycosides highlighted lower reaction energy barriers towards glucoside substrates,emphasizing CtMaT1's preference for ***,a mutant CtMaT1H36A with notably increased di-malonylation activity was *** underlying molecular mechanism was illuminated through MM/GBSA binding free energy *** study significantly advances the understanding of plant acyltransferases from both functional and protein structural perspectives,while also providing a versatile tool for enzymatic malonylation applications in pharmacology.

关键词： Plant acyltransferase Malonyltransferase Malonylated glycosides enzymatic catalysis Enzyme promiscuity

Mg-gallate metal-organic framework-based sprayable hydrogel for continuously regulating oxidative stress microenvironment and promoting neurovascular network reconstruction in diabetic wounds

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Bioactive Materials 2024年第8期38卷 181-194页

作者： Chenxi Lian Jiawei Liu Wenying Wei Xiaopei Wu Takashi Goto Haiwen Li Rong Tu Honglian Dai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China National Energy Key Laboratory for New Hydrogen-ammonia Energy Technologies FoshanXianhu LaboratoryFoshan528200China Chaozhou Branch of Chemistry and Chemical Engineering Guangdong Laboratory Chaozhou 521000China

Chronic diabetic wounds are the most common complication for diabetic *** to high oxidative stress levels affecting the entire healing process,treating diabetic wounds remains a ***,we present a strategy for continuously regulating oxidative stress microenvironment by the catalyst-like magnesium-gallate metal-organic framework(Mg-GA MOF)and developing sprayable hydrogel dressing with sodium alginate/chitosan quaternary ammonium salts to treat diabetic *** quaternary ammonium salts with antibacterial properties can prevent bacterial *** continuous release of gallic acid(GA)effectively eliminates reactive oxygen species(ROS),reduces oxidative stress,and accelerates the polarization of M1-type macrophages to M2-type,shortening the transition between inflammation and proliferative phase and maintaining redox ***,magnesium ions adjuvant therapy promotes vascular regeneration and neuronal formation by activating the expression of vascular-associated *** hydrogel dressings with antibacterial,antioxidant,and inflammatory regulation rapidly repair diabetic wounds by promoting neurovascular network reconstruction and accelerating re-epithelialization and collagen *** study confirms the feasibility of catalyst-like MOF-contained sprayable hydrogel to regulate the microenvironment continuously and provides guidance for developing the next generation of non-drug diabetes dressings.

关键词： Chronic diabetic wounds Bioactive MOF Antioxidant Anti-inflammation enzymatic catalysis Neurovascular network reconstruction

Blue Luminescent Properties of enzymatic Catalyzed Polymerizedp－Phenyl Phenol

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Chemical Research in Chinese Universities 1994年第3期10卷 193-196页

作者： MA Yu-guang, and SHEN Jia-cong(The Key Laboratory for Molecular Spectra and Structure,Jilin University, Changchun, 130023 )TANG Jian-guo and LIU Shi-yong(The National Lab.of Integivted Optic Electronics, Jilin University, Changchun, 130023)MA Lin(The Nati

hoton emission properties of polyphenylphenol (PPP) synthesized in the pres-ence of a newly-found enzymatic catalyst are reported. The photoluminescence peakexcited by the light at 350 nm is at about 370-420 nm. The absorption band edgesand photon emitting peaks of the polymer were found dependent on the conjugatedlengths of the polymer. In the transient luminescence measurement the lifetime ofPL decay was determined to be 2. 0 ns which is supposed as the evidence of polaronexcitation recombination.

关键词： Blue light Poly(p-phenyl phenol) enzymatic catalysis

Asymmetric catalysis in synthetic strategies for chiral benzothiazepines

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Green Synthesis and catalysis 2020年第1期1卷 12-25页

作者： Haifeng Wang Shuangxi Gu Qiongjiao Yan Li Ding Fen-Er Chen School of Chemical Engineering&Pharmacy Wuhan Institute of TechnologyWuhan 430205China Pharmaceutical Research Institute Wuhan Institute of TechnologyWuhan 430205China Engineering Center of catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial catalysis for Chiral Drugs Shanghai 200433China

Chiral benzothiazepines constitute the core structures of many foremost pharmaceuticals with diverse biological activities endowed by their unique scaffolds,which poses a great challenge to organic chemists and pharmaceutical *** review provides a concise overview for the asymmetric synthesis of chiral benzothiazepine derivatives,focusing on advances in asymmetric catalysis,including metal catalysis,small-molecule organocatalysis and enzymatic *** catalytic asymmetric reactions,involving asymmetric epoxidation,reduction,dihydroxylation,hydrogenation,aldol reaction and other sulfa-Michael addition,have emerged as powerful strategies for the rapid construction of chiral benzothiazepine through single or multistep *** booming asymmetric synthetic methodology affords us instructive clues for the highly efficient preparation of chiral benzothiazepines,facilitating their large-scale preparation and diversity-oriented synthesis.

关键词： Chiral benzothiazepine Asymmetric catalysis Metal catalysis enzymatic catalysis Organic catalysis

Recent Progress on Biocatalysis and Biotransformations in Ionic Liquids

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Chinese Journal of Chemical Engineering 2004年第4期12卷 543-549页

作者：娄文勇宗敏华吴虹许若 Department of Biotechnology South China University of Technology Guangzhou 510640 China Department of Biotechnology South China University of Technology Guangzhou 510640 Chinaonic liquids have negligibly low vapor pressure high stability and polarity. They are regarded as green solvents. Enzymes especially lipases as well as whole-cell of microbe are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases remarkable results with respect to yield catalytic activity stability and (enantio- regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.

Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.

关键词： ionic liquids biocatalysis and biotransformations enzymatic catalysis