JOURNAL OF CHEMICAL RESEARCH
·
2017
·
IF 0.646
Xiaoyun Ma,Jun Ao,Zhengjian Chen,Yi Liu
A mild one-pot method for the direct conversion of aryl, heteroaryl and alkyl aldehydes into nitriles was achieved by forming the corresponding oximes in situ with NH2OH and allowing them to react with CuO and acetonitrile. Yields of the 13 nitriles prepared were moderate to very good (62–91%).
研究领域:
有机化学
·
催化反应
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2015
·
IF 4.494
Shumei Fang,Xuejiao An,Hongyuan Liu,Yi Cheng,Ning Hou,Lu Feng,Xinning Huang,Chunyan Li
Nitriles are common environmental pollutants, and their removal has attracted increasing attention. Microbial degradation is considered to be the most acceptable method for removal. In this work, we investigated the biodegradation of three aliphatic nitriles (acetonitrile, acrylonitrile and crotononitrile) by Rhodococcus rhodochrous BX2 and the expression of their corresponding metabolic enzymes. This organism can utilize all three aliphatic nitriles as sole carbon and nitrogen sources, resulting in the complete degradation of these compounds. The degradation kinetics were described using a first-order model. The degradation efficiency was ranked according to t 1/2 as follows: acetonitrile > trans-crotononitrile > acrylonitrile > cis-crotononitrile. Only ammonia accumulated following the three nitriles degradation, while amides and carboxylic acids were transient and disappeared by the end of the assay. mRNA expression and enzyme activity indicated that the tested aliphatic nitriles were degraded via both the inducible NHase/amidase and the constitutive nitrilase pathways, with the former most likely preferred.
研究领域:
环境微生物学
·
生物修复
·
酶学
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产品关联
DOI
PubMed
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
·
2013
·Vol. 30
·期 1
·245-252
·
IF 1.262
Wang Hualei,Li Guinan,Li Mingyang,Wei Dongzhi,Wang Xuedong
In this study, a novel nitrilase gene from Rhodobacter sphaeroides was cloned and overexpressed in Escherichia coli . The open reading frame of the nitrilase gene includes 969 base pairs, which encodes a putative polypeptide of 322 amino acid residues. The molecular weight of the purified native nitrilase was about 560 kDa determined by size exclusion chromatography. This nitrilase showed one single band on SDS-PAGE with a molecular weight of 40 kDa. This suggested that the native nitrilase consisted of 14 subunits with identical size. The optimal pH and temperature of the purified enzyme were 7.0 and 40 °C, respectively. The kinetic parameters V
max and K
m toward 3-cyanopyridine were 77.5 μmol min −1 mg −1 and 73.1 mmol/l, respectively. The enzyme can easily convert aliphatic nitrile and aromatic nitriles to their corresponding acids. Furthermore, this enzyme demonstrated regioselectivity in hydrolysis of aliphatic dinitriles. This specific characteristic makes this nitrilase have a great potential for commercial production of various cyanocarboxylic acids by hydrolyzing readily available dinitriles.
研究领域:
微生物学
·
生物化学
·
酶学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 23
·5668
·
IF 4.2
Dengxun Ren,Zexu Fan,Jiaqu Zhang,Yi Xu,Xianzhong Tang,Mingzhen Xu
To study the properties of cyclotriphosphazene (CTP)-containing phthalonitriles, a branched phthalonitrile containing CTP (CTP–PN) with self-catalytic behavior was designed and synthesized. The structure of CTP–PN was characterized by FT–IR (Fourier transform infrared spectroscopy), MS (mass spectroscopy), 1 H–NMR (proton nuclear magnetic resonance spectroscopy), and 13 C–NMR (carbon nuclear magnetic resonance spectroscopy). Then, the curing reaction of CTP–PN was studied using DSC (differential scanning calorimetry) and DRA (dynamic rheological analysis). The results show that the curing reaction of CTP–PN is initiated at 200 °C. Additionally, the change in the viscosity of CTP–PN as a function of the temperature was investigated. After curing at different temperatures, the generated structures were characterized by FT–IR. The fracture morphology and thermomechanical properties of cured CTP–PN were scanned and studied using SEM (scanning electron microscopy) and TMA (thermomechanical analysis), respectively. The results demonstrate that CTP–PN exhibits a smooth fracture surface and possesses a relatively low CTE (coefficient of linear thermal expansion) of approximately 25 ppm/°C at 285 °C. A T d5% (temperature at which 5% weight loss occurs) of as high as 405 °C can be obtained for cured CTP–PN, and its char yield at 800 °C exceeds 70% in N 2 . FT–IR and XPS (X-ray photoelectron spectroscopy) were used to study the thermal decomposition of cured CTP–PN, indicating that it remains stable below 350 °C. With an increasing temperature, there is decomposition first of CTP and P–NH–Ph and C–O–C bonds (>350 °C) and then nitrogen-containing aromatic heterocycles (>500 °C), ultimately resulting in the formation of P-containing residual char.
研究领域:
材料科学
·
化学
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产品关联
DOI
PubMed
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
·
2025
·Vol. 41
·期 3
·1-11
·
IF 4.2
Liu Ming-Yu,Wang Yu-Yue,Li Han-Zhi,Luo Xue-Mei,Feng Jia-Xun,Zhao Shuai
Nitriles exhibit acute cytotoxicity to human and animal cells. Nitrilase is a green biocatalyst that can directly convert nitrile into nontoxic carboxylic acids and ammonia. However, the nitrilases capable of degrading 3-butenenitrile and 4-pentenenitrile derived from glucosinolate present in rapeseed meals are still limited. This study expressed the nit rilase 2 gene from bacterium Paraburkholderia g raminis ( PgNIT2 ) in Escherichia coli . The purified recombinant nitrilase rPgNIT2 showed specific activities of 5.94 U/mg and 6.66 U/mg when using 3-butenenitrile and 4-pentenenitrile as substrates at the optimal pH 7.0 and temperature 45 °C. The substrate binding pocket of PgNIT2 comprising 12 amino acids was required for rPgNIT2 activity. Remarkably, the specific activity of mutant enzyme A190I increased by 68.3% and 57.3%, respectively, against 3-butenenitrile and 4-pentenenitrile compared with the wild-type enzyme. Furthermore, the A190I showed improved thermostability and hydrolysis ability towards 3-butenenitrile and 4-pentenenitrile compared with rPgNIT2 but shared the same optimal pH and temperature. These results provided theoretical guidance for engineering of bacterial nitrilases used for rapeseed meal detoxification.
研究领域:
生物化学
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分子生物学
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DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 72
·58393-58402
·
IF 3.84
Yuanyuan Xu,Jinming Sun,Hou Chen,Liangjiu Bai
This study describes reversible addition–fragmentation chain-transfer (RAFT) polymerization initiated by cobalt(III) acetylacetonate (Co(acac)3). With Co(acac)3 as the initiator, RAFT polymerization of acrylonitrile was achieved at 90 °C mediated by 2-cyanoprop-2-yl dithionaphthalenoate. The polymerization exhibited “living”/controlled characteristics with a molar mass distribution as low as 1.25. Homogeneous polyacrylonitrile nanofibers (PAN-nFs) were produced via the electrospinning technique. FTIR, SEM and TGA analyses revealed aminated-PAN-nFs (APAN-nFs) were successfully obtained via ethylenediamine grafting onto the surface of PAN-nFs. The adsorption interaction between methyl orange (MO) dye and APAN-nFs is discussed in detail. The maximum saturation adsorption capacity was 102 mg g−1. The adsorption kinetics followed a pseudo-second-order model. The Langmuir model was better for interpreting the isothermal process for MO and APAN-nFs. The Dubinin–Radushkevich isothermal model indicated that the adsorption proceeded chemically. Intraparticle diffusion was not the only rate-limiting step. The thermodynamics properties indicated the adsorption process was exothermic and spontaneous in nature. The MO dye adsorbed by APAN-nFs could be reversibly desorbed by an aqueous solution of pH = 1. APAN-nFs could be recycled efficiently.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2017
·
IF 6.035
Xiaoming Yan,Runlian Deng,Yu Pan,Xiaowei Xu,Issam El Hamouti,Xuehua Ruan,Xuemei Wu,Ce Hao,Gaohong He
Hydroxide exchange membrane fuel cells (HEMFCs) are attracting growing interest owing to their advantages such as low cost and high power density. However, their applications are hindered due to the poor stability of the membrane. Here, we proposed a novel strategy to improve the alkaline stability of hydroxide exchange membranes (HEMs) using the interactions between strongly polar nitrile groups and side-chain functional cations. A poly(ether nitrile) (PEN) was synthesized by the polycondensation of bisphenol A and 2,6-difluorobenzonitrile, and then imidazolium and morpholinium functional groups were integrated by the typical chloromethylation-functionalization method. The existence of the interactions between nitrile groups and cation groups i.e. imidazolium and morpholinium, was proved by the density functional theory calculations. The interactions have two positive effects that contribute to the improvement of the alkaline stability of the PEN based membranes. On the one hand, they increase the LUMO energies of the functional groups; and on the other hand they reduce the free volume around hydrated cationic groups. As a result, PEN based membranes showed much better alkaline stabilities compared to the membrane based on commercial polysulfone that has a similar chemical structure . In addition, given similar swelling ratios, PEN based membranes exhibited higher hydroxide conductivities than simple polysulfone based ones.
研究领域:
化学工程
·
材料科学
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产品关联
DOI
高影响因子
SYNTHETIC COMMUNICATIONS
·
2024
·
IF 1.8
Xiaoyun Ma,Xiaoyan Wan,Jun Zhao
A method for the preparation of nitriles from primary amides using trichloroacetonitrile and a catalytic amount of cupric acetate is described. Using this method, amides including aromatic amides, aromatic heterocyclic amides and aliphatic amides were converted into the corresponding nitriles in moderate to good yields. Trichloroacetonitrile reacted with amide in the presence of cupric acetate to form trichloroacetamide, which has been isolated and confirmed.
研究领域:
有机化学
·
合成化学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Liying Xu,Zhenlei Wang,Saidi Wang,Yanrong Liu,Xingmei Lu,Bing Yang,Ke Wang,Lijun Han,Jiayu Xin,Suojiang Zhang
The electrochemical dimerization of acrylonitrile (AN) to adiponitrile (ADN) is an essential process for nylon-66 production, but this process still faces many challenges such as low energy conversion efficiency and poor selectivity. Herein, various ionic liquids (ILs) were used as electrolyte additives to evaluate their effects on the electrochemical dimerization of AN. The addition of IL significantly enhanced the performance of the electrolytic reaction and inhibited the hydrogen evolution reaction (HER). The electrolyte containing Tetrabutylphosphonium bromide (TBPB) showed the highest faraday efficiency of adiponitrile (FEADN) of 84.5% and excellent stability at an optimal current density of 200 mA cm–2. Molecular dynamics (MD) simulations revealed that TBPB was uniformly dispersed in the electrolyte and formed a “long brush” hydrophobic layer with appropriate wettability on the electrodes. Moreover, it was observed that ILs with a more symmetrical cationic structure exhibited a better hydrophobic layer effect, favoring the dimerization of AN to ADN.
研究领域:
化学工程
·
材料科学
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产品关联
DOI
高影响因子
BIOPROCESS AND BIOSYSTEMS ENGINEERING
·
2017
·Vol. 40
·期 6
·901-910
·
IF 1.87
Zhang Qiang,Gong Jin-Song,Dong Ting-Ting,Liu Ting-Ting,Li Heng,Dou Wen-Fang,Lu Zhen-Ming,Shi Jin-Song,Xu Zheng-Hong
3-Hydroxypropionic acid (3-HP) is an important platform chemical in organic synthesis. Traditionally, 3-HP was produced by chemical methods and fermentation process. In this work, a novel enzymatic method was developed for green synthesis of 3-HP. A yeast strain harboring nitrile-hydrolyzing enzyme was newly isolated from environmental samples using 3-hydroxypropionitrile (3-HPN) as the sole nitrogen source. It was identified to be Meyerozyma guilliermondii CGMCC12935 by sequencing of the 18S ribosomal DNA and internal transcribed spacer, together with analysis of the morphology characteristics. The catalytic properties of M. guilliermondii CGMCC12935 resting cells were determined, and the optimum activity was achieved at 55 °C and pH 7.5. The enzyme showed broad substrate specificity towards nitriles, especially 3-HPN, aminoacetonitrile and 3-cyanopyridine. The presence of Ag + , Pb 2+ and excess substrate inhibited the enzyme activity, whereas 5% (v/v) ethyl acetate had a positive effect on the enzyme activity. M. guilliermondii CGMCC12935 resting cells by addition of 3% glucose could thoroughly hydrolyze 500 mM 3-HPN into 3-HP within 100 h and the maximal accumulative production of 3-HP reached 216.33 mM, which was over twofolds than the control group with no additional glucose. And this work would lay the foundation for biological production of 3-HP in industry.
研究领域:
生物化学
·
工业微生物学
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DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2011
·Vol. 49
·期 22
·4721-4724
·
IF 3.894
Hou Chen,Min Zhang,Mengmeng Yu,Hongyan Jiang
Graphical Iron tube was applied as catalyst source in the design of continuous SET-LRP of AN without any ligand using BPN as initiator in NMP and DMF, respectively. First-order kinetics of polymerization with respect to the monomer concentration, linear increase of the molecular weight, and narrow polydispersity with monomer conversion showed the controlled radical polymerization characters. An increase in polymerization rate in NMP was observed compared with in DMF. The living feature of PAN was verified by chain extensions of PAN with MMA.
研究领域:
化学工程
·
高分子科学
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2012
·Vol. 50
·期 24
·5170-5176
·
IF 3.919
Yue-Cheng Qian,Xiao-Jun Huang,Chen Chen,Ning Ren,Xu Huang,Zhi-Kang Xu
The thiol–ene radical addition reaction has been successfully used to synthesize polyphosphazene derivatives. Poly[bis(allylamino)phosphazene] with pendant allyl groups was reacted with different thiol reagents under UV irradiation. These thiol reagents include 1-pentanethiol, 3-mercaptopropionic acid, 3-mercapto-1,2-propane-diol, and 2,3,4,6-tetra-O-acetyl-1-thio-β- D -glucopyranose. 1 H NMR analyses confirm that the allyl polyphosphazene can be quantitatively modified by the mercaptans. In total, 100% conversion of the allyl groups was reached in <60 min toward the first three mercaptans, whereas about 80% conversion of the allyl groups was reached after 120-min reaction toward the thioglucose. This method is a facile route for the synthesis of functional polyphosphazenes without the needs for protection/deprotection procedures. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）