ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS
·
2014
·
IF 3.043
Chenxi Ning,Erzheng Su,Dongzhi Wei
Lodderomyces elongisporus LH703 isolated from soil samples contained three novel aldo–keto reductases (AKRs) (LEAKR 48, LEAKR 49, and LEAKR 50). The three enzymes were cloned, expressed, and purified to homogeneity for characterization. These three AKRs shared <40% amino acid identity with each other. LEAKR 50 was identified as a member of AKR3 family, whereas the other two LEAKRs were identified as members of two novel AKR families, respectively. All the three AKRs required nicotinamide adenine dinucleotide phosphate as a cofactor. However, they showed diverse characteristics, including optimum catalyzing conditions, resistance to adverse reaction conditions, and substrate specificity. LEAKR 50 was estimated to be a promising biocatalyst that could reduce ethyl 4-chloroacetoacetate with high enantiomeric excess (98% e. e.) and high activity residue under adverse conditions.
✓ 已验证
DOI
PubMed
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Weiyou Zhou,Jiayin Huang,Anwei Wang,Jia Cui,Jie Yao,Tao Hou,Shuliang Ji,Mingyang He,Zhonghua Sun
An efficient heterogeneous catalytic system for the [4 + 2] annulation reactions between tertiary anilines and tetrahydrofuran has been developed based on CuCoFe layered double oxide in the study. Cu + species was believed to play the crucial role in the catalytic transformation, and synergistic effect between Cu and CoFe species was observed in the reaction. Various tertiary anilines could be tolerated by the present catalytic system. A series of control experiments were conducted to determine the reaction intermediates. A distinctive reaction mechanism has been described for the annulation reaction based on these results and kinetic isotopic effects experiments.
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
·
2013
·
IF 1.773
Kashif Naeem,Feng Ouyang
The photocatalytic degradation of phenol and 4-chlorophenol (4-CP) in aqueous suspensions with the use of titanium dioxide (TiO 2 ) under UV irradiation was examined. The effects of different supporting materials mixed physically with TiO 2 were studied to achieve maximum degradation efficiency. Among the three supports, namely activated carbon (AC), silica (SiO 2 ) and zeolite (ZSM-5), all exhibited paramount efficiency for degradation of phenol and 4-CP and was better than TiO 2 alone. The optimum concentration was found to be 50 mg for all supporting materials. The efficiency order of the three supports was as follows: AC > ZSM-5 > SiO 2 , respectively. Whilst, the degradation of phenol and 4-CP was improved from 70.6% to 87.6% and 80.6% to 89.7%, respectively, within 120 min photocatalysis in the presence of optimal amount of AC. The degradation was also comparatively enhanced in the presence of cheaper rice husk and the activity was closed to ZSM-5 and lower than AC.
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
·
2013
·
IF 3.458
Xiaomin Yang,Lin Zhao,Laszlo Almasy,Vasil M. Garamus,Aihua Zou,Regine Willumeit,Saijun Fan
Chemically modified tetracyclines (CMTs) have been reported to strongly inhibit proliferation and metastasis of various cancers, but their efficacy is restricted by poor water solubility. In the present study, a hydrophilic 4-dedimethylamino sancycline (CMT-3) loaded nanostructured lipid carrier (CMT-3/NLC) was produced by high pressure homogenization (HPH). The physical properties of CMT-3/NLC formulations were characterized by dynamic light scattering (DLS), high efficiency liquid chromatography (HPLC), atomic force microscopy (AFM), scanning electron microscopy (SEM), small-angle neutron scattering (SANS), small-angle X-ray scattering (SAXS) and wide-angle X-ray powder diffraction (XRD). The lipid and surfactant ingredients, as well as drug/lipid concentrations (m/m) were optimized to produce stable and sustained NLC formulations. In vitro cytotoxicity of CMT-3/NLC against HeLa cells was evaluated by MTT assay. The diameter of CMT-3/NLC was found to increase from 153.1 ± 3.0 nm to a maximum of 168.5 ± 2.0 nm after 30 days of storage, while the entrapment efficiency remained constant at >90%. CMT-3/NLC demonstrated a burst-sustained release profile in release media with different pH, a property attributed to the 3-dimensional structure of CMT-3/NLC. Cell uptake and localization studies indicated that NLC reached the cytoplasm and could thereby facilitate CMT-3 entry into HeLa cells.
✓ 已验证
DOI
PubMed
高影响因子
TALANTA
·
2021
·
IF 6.057
Lichen Gou,Xiaoliang Zeng,Huan Du,Ling Li,Yunfei Tian,Xiandeng Hou,Li Wu
Herein, a facile and fast surface-enhanced Raman scattering (SERS) method with ratiometric strategy was developed for detection of 4-methylimidazole (4-MI). Via a chemical derivatization reaction with 3-amino-5-mercapto-1,2,4-triazole (AMTA) diazonium salts, 4-MI could be converted to SERS-sensitive species. The SERS intensity ratio between the peaks at 1243 cm −1 and 1110 cm −1 (I 1243 /I 1110 ) was used for the quantification of 4-MI. In addition, the method sensitivity was further improved by the aggregation of beta-cyclodextrin-modified Ag nanoparticles (beta-CD-AgNPs). Under the optimal conditions, the limit of detection (LOD) and the limit of quantification (LOQ) for 4-MI were 1.7 nM (S/N = 3) and 5.7 nM (S/N = 10), respectively. The relative standard deviation (RSD) for 0.5 μM 4-MI was 8.2% (n = 20). This method was successfully used for the determination of 4-MI in cola samples with recoveries ranging from 92% to 106%. The present method is convenient, sensitive, selective, reliable and may have a promising application in determination of the compounds with an imidazole ring containing active hydrogen atoms .
✓ 已验证
DOI
PubMed
高影响因子
SYNTHESIS-STUTTGART
·
2013
·Vol. 45
·期 24
·3349-3354
·
IF 2.5
Haidong Wei,Tianbin Li,Yue Zhou,Lihong Zhou,Qingle Zeng
Alkyl halides, including heteroarylmethyl and arylmethyl halides, bromoacetate, and cinnamyl bromide, are readily prepared via halogenation from basic raw materials, even using green processes. It is essential to replace their downstream products with them to prepare medicinally important heterocycles quinazolin-4(3H)-ones. Copper(I) bromide catalyzed domino reaction of alkyl halides and anthranilamides under air affords 2-substituted quinazolin-4(3H)-ones in good to excellent yields and with wide functional group tolerance. A mechanism for a copper(I) bromide involved organometal-catalyzed reaction via a four-step domino reaction is proposed.
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2017
·Vol. 7
·期 10
·303
·
IF 3.553
Haijiao Lu,Jingkang Wang,Hongxun Hao,Ting Wang
With a large specific surface area, high reactivity, and excellent adsorption properties, nano zerovalent iron (nZVI) can degrade a wide variety of contaminants in wastewater. However, aggregation, oxidation, and separation issues greatly impede its wide application. In this study, MoS2/Fe3O4/nZVI nanocomposites were successfully synthesized by a facile step-by-step approach to overcome these problems. MoS2nanosheets (MNs) acted as an efficient support for nZVI and enriched the organic pollutants nearby, leading to an enhanced removal efficiency. Fe3O4nanoparticles (NPs) could not only suppress the agglomeration and restacking of MNs, but also facilitate easy separation and recovery of the nanocomposites. The synergistic effect between MNs and Fe3O4NPs effectively enhanced the reactivity and efficiency of nZVI. In the system, Cr(VI) was reduced to Cr(III) by nZVI in the nanocomposites, and Fe2+produced in the process was combined with H2O2to further remove 4-Chlorophenol (4-CP) through a Fenton reaction. Furthermore, the nanocomposites could be easily separated from wastewater by a magnet and be reused for at least five consecutive runs, revealing good reusability. The results demonstrate that the novel nanocomposites are highly efficient and promising for the simultaneous removal of Cr(VI) and 4-CP in wastewater.Keywords:nZVI;modification;nanocomposites;Cr(VI);4-CP;Fenton reaction;pollution treatment;recyclability;wastewater
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2013
·
IF 1.684
Xiao-Qiu Dou,Ping Li,Siqing Lu,Xiaobing Tian,Yitian Tang,June D. Mercer-Chalmers,Chuan-Liang Feng,Di Zhang
The highly directional interactions among complex gelators of 2,6-pyridinedicarboxylic acid and 4-hydroxypyridine are investigated, which lead to the formation of ordered one-dimensional fibers with diameters of 500 nm ~ 2 μm. By scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, 1 H nuclear magnetic resonance ( 1 H NMR) spectroscopy, ultraviolet–visible (UV–vis) spectroscopy, and X-ray powder diffraction (XRD), the co-assembly of the complex into straight fibers under the function of multiple directional hydrogen bonds and π–π stackings is proved. The strong and directional interactions lead to rich dynamic behavior and high degrees of internal order among the complex gelators. The ordered one-dimensional co-assemblies possess useful functions in templated synthesis, molecular recognition , enzyme immobilization, and other biochemistry fields.
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Chuankai Fu,Shuaifeng Lou,Xing Xu,Can Cui,Can Li,Pengjian Zuo,Yulin Ma,Geping Yin,Yunzhi Gao
Owing to high safety and considerable energy density , rechargeable all-solid-state lithium-metal polymer batteries (ASSLPBs) with organic-inorganic composite solid-state electrolytes (CSSEs) have been recognized as one of the most promising battery systems. However, 4 V or above-class ASSLPBs still suffer serious capacity degradation arising from the complex interface issues between the electrode and electrolyte. Herein, for the first time, we find the oxidation decomposition of TFSI - anion and further interaction with PEO polymer matrix in the LiNi 0.8 Co 0.1 Mn 0.1 LiO 2 (NCM811)/CSSEs (PEO-LiTFSI-LAGP)/Li cell, which cause continuous damage to the interfacial stability and persistent capacity degradation. Increasing the ratio of LAGP filler in CSSEs membrane and employing PEO-LiBOB electrolyte in composite cathode were demonstrated effective. As a consequence, the ASSLPBs show high reversibility, and high capacity retention up to 88% (3.0–4.2 V) and 78% (3.0–4.3 V) after 100 cycles with the charge/discharge current density of 30 mA g −1 (35 °C). The understanding on capacity degradation mechanism, along with the positive improvement strategies validly boosts the development and promising application of 4 V-class ASSLPBs.
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2014
·
IF 5.825
Rui Li,Kangbing Wu,Changxian Liu,Yin Huang,Yanying Wang,Huaifang Fang,Huijuan Zhang,Chunya Li
A novel ionic liquid, 4-amino-1-(3-mercapto-propyl)-pyridine hexafluorophosphate (AMPPH), was successfully synthesized and characterized. Subsequently, AMPPH was used as a functional monomer to fabricate AMPPH-modified gold nanoparticles (AMPPH–AuNPs) via a one-pot synthesis method. The as-prepared AMPPH–AuNPs were confirmed with transmission electron microscopy and X-ray photoelectron spectroscopy. AMPPH–AuNPs were used to construct a biocompatible interface to immobilize rabbit anti-human IgG (anti-HIgG) onto a glassy carbon electrode (GCE) surface, followed by a cross-linking step with glutaraldehyde to fabricate an anti-HIgG–AMPPH–AuNPs/GCE. The nonspecific binding sites were enclosed with bovine serum albumin (BSA) to develop an immunosensor for human IgG. Electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry were used to investigate the electrochemical properties of the developed immunosensor. The results indicate that AMPPH–AuNPs can improve the immunosensing performance. The current response of the immunosensor was found linearly related to human IgG concentration in the range of 0.1–5.0 ng mL–1 and 5.0–100.0 ng mL–1. The detection limit is estimated to be 0.08 ng mL–1 (S/N = 3). The obtained immunosensor was successfully applied to the analysis human IgG immunoglobulin in human serum, and the results were well consistent with ELISA method.
✓ 已验证
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2018
·
IF 2.616
Mujiao Zhang,Peiyuan Yao,Shanshan Yu,Tongcun Zhang,Qiaqing Wu,Dunming Zhu
An efficient method for the production of 4-cyanobenzoic acid from terephthalonitrile was developed by using a novel nitrilase from Pantoea sp. AS-PWVM4 (PaNIT). Under the optimized reaction conditions (pH 8.0 and 37 °C), up to 100 g/L substrate concentration was almost completely converted to 4-cyanobenzoic acid with wet whole cells loading of 5.0 wt% in 4 h and the isolated yield was 91%. The substrate concentration, yield and productivity (26.13 g/(L h)) are much higher than those in the previous studies. Furthermore, PaNIT has broad substrate specificity of catalyzing the hydrolysis of various aromatic nitriles and aliphatic nitriles. These results suggest that PaNIT is a valuable nitrilase with potential practical applications.
✓ 已验证
DOI
高影响因子
BIOLOGICAL & PHARMACEUTICAL BULLETIN
·
2013
·
IF 1.849
Zhao-Bo Li,Chang-Fu Li,Jia Li,Yan-Sheng Zhang
As part of the efforts to understand isoflavonoid metabolism in Pueraria lobata at the molecular level, the cDNAs encoding two divergent 4-coumarate:coenzyme A ligases (4CLs, designated Pl4CL1 and Pl4CL2, respectively) were isolated from P. lobata roots. Sequence analysis revealed that Pl4CL1 had an N-terminal extension of twenty-one amino acid residues compared to Pl4CL2. Phylogenetic analysis showed that Pl4CL1 and Pl4CL2 fell into angiosperm Class II and Class I, respectively. Through in vitro biochemical assays, both Pl4CLs were found to have the capacity to utilize 4-coumarate and trans-cinnamate as substrates, while neither of them could convert sinapate. Pl4CL2 had a broader substrate specificity than Pl4CL1. The affinity of Pl4CL1 for 4-coumarate was 2.6-fold higher than that of Pl4CL2 (with the Km values of 3.5 µM and 9.1 µM, respectively). Combining the dataset including gene expression profiles, metabolites measurements, and biochemical properties, our results indicated that Pl4CL1, just as other angiosperm Class II 4CLs, might play a role in isoflavone biosynthesis in P. lobata, while Pl4CL2 belongs to angiosperm Class I, and may function as a housekeeping enzyme concerning lignification.
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）