ACS Catalysis
·
2025
·
IF 13.1
Yong Tang,Yaning Xu,Xuan Zhang,Chunyu Wang,Danning Zhao,Fengxi Li,Lei Wang
In this study, the asymmetric decarboxylative Mannich reaction (DMR) provides an attractive method for assembling C–N bonds to synthesize high-value-added nitrogenous scaffolds. Here, we report an enzyme-controlled method for the asymmetric DMR of cyclic sulfonamides with β-ketone esters. The method utilizes two types of enzymes, namely, copper artificial metalloenzyme (Cu-ArM) and commercial lipase (Novozym 435), to control the bidirectional enantioselectivity in DMR. The Cu-ArM is produced by anchoring a biotinylated Cu-complex (4-OHPIP-biotin*CuI) within wild-type streptavidin (WT-Sav). The resulting Cu-ArM catalyzes the asymmetric DMR to obtain a series of R-configurated β-sulfonamide ketones with good yield and enantioselectivity. By contrast, the S-configurated β-sulfonamide ketones are obtained with satisfying stereoselectivity and yield when Novozym 435 is used as the catalyst. Molecular dynamics (MD) simulations of both enzymes, along with preliminary stereochemical model analysis, elucidate the key site contact leading to good catalytic performance. Furthermore, MD simulations offer a plausible explanation for the superior reactivity of cyclic imines compared to noncyclic imines.
研究领域:
有机化学
·
生物催化
·
酶工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 60
·37636-37642
·
IF 3.108
Qiao-Feng Zheng,Mo Yu,Shu-Shen Liu,Fu Chen
Hormesis is a biphasic concentration–response relationship. During the luminescence inhibition test of Vibrio qinghaiensis sp.-Q67 (Q67), some organic solvents display the hormesis phenomenon. However, the mechanism of hormesis with respect to organic solvents remains unclear. This study focuses on luciferase, which is the key factor in luminescent reactions, and explores its role in the mechanism of hormesis. Q67 luciferase has two subunits, α and β. Molecular docking and molecular dynamics simulations were carried out by taking organic solvents as ligand and the two subunits as receptor. In addition, the binding free energies of the complexes formed by the ligand and Q67 luciferase were calculated. The results showed that the organic solvent ligands exhibiting hormesis bind to the β subunit first, while those that do not exhibit hormesis bind more easily to the α subunit. The hormetic organic solvents bind to β subunit first at low concentration, and change the flexibility of residues Ser145–Arg165 located on the α subunit; this enables flavin mononucleotide (FMN) to bind to the α subunit, exhibiting the hormesis phenomenon. With the increasing concentration, redundant molecules start to bind to the α subunit and compete with/block FMN binding to the α subunit, resulting in inhibition.
研究领域:
生物化学
·
分子生物学
·
环境毒理学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2012
·
IF 4.98
Zheng-Zheng Zou,Hui-Lei Yu,Chun-Xiu Li,Xin-Wen Zhou,Chihiro Hayashi,Jie Sun,Bao-Hong Liu,Tadeyuki Imanaka,Jian-He Xu
A new β-glucosidase (DtGH) representing 40% identity with an apple seed glycosidase (ASG) was cloned from Dictyoglomus thermophilum . DtGH showed extremely high thermostability in aqueous solution, with half-lives of 533, 44, and 5 h measured at 70, 80 and 90 °C, respectively. Therefore it was used for direct glycosylation of n -octanol at 70 °C instead of 50 °C as usually. As a result, the glucose based conversion was increased by 27%, but the time spent to reach equilibrium was decreased from 7 d to 3 d. This enzyme also exhibited excellent stability under the reaction environment, retaining 70–80% of its initial activity after 7 d of incubation at 70 °C in either 1.7 M glucose solution or octanol-aqueous (85:15, v/v) system. It could retain part of synthetic activity even in boiling water. Owing to the strong glucose-tolerance and extremely high thermostability, DtGH should be promising for various glucosides synthesis.
研究领域:
生物化学
·
酶工程
✓ 已验证
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Yanyan Zhao,Shuhao Wang,Zhuan Yi,Yong Zhou,Congjie Gao
A novel β-cyclodextrin (β-CD)/polyamide film reverse osmosis (RO) membrane was prepared by in situ interfacial polymerization via mixing β-CD with m-phenylenediamine in the aqueous phase prior to reaction with trimesoyl chloride. The effects of the β-CD concentration on the morphology and separation performance of the RO membrane were studied. β-CD was employed to improve the pure water flux of the membrane. When the concentration of β-CD in aqueous solution was 1.5% (w/v), both the rejection of NaCl and the pure water flux were maintained at a high level. In this case, water flux of the β-CD-modified RO membrane was nearly1.52 times that of the β-CD-free polyamide membrane. This increase might have been caused by the high concentration of β-CD hydrophilic hydroxyl groups, which appeared to directly improve the performance of the composite film. In addition, the unique properties of the resulting membrane, including the loosely cross-linked structure formed by β-CD and the polyamide film, the intramolecular cavity existed in β-CD and the affinity of β-CD to water molecules, was ascribed as the reasons for the improved performance of higher permeability.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2014
·Vol. 37
·期 24
·3738-3744
·
IF 2.594
Jiliang Cao,Jinchao Wei,Ke Tian,Huanxing Su,Jianbo Wan,Peng Li
A capillary zone electrophoresis method was developed for the simultaneous determination of seven phenolic acids, including protocatechuic aldehyde ( 1 ), salvianolic acid C ( 2 ), rosmarinic acid ( 3 ), salvianolic acid A ( 4 ), danshensu ( 5 ), salvianolic acid B ( 6 ), and protocatechuic acid ( 7 ), in Danshen and related medicinal plants. A running buffer composed of 20 mM sodium tetraborate adjusted to pH 9.0, and containing 12 mM β-cyclodextrin as modifier. Baseline separation was achieved within 17 min running at the voltage of 20 kV, temperature of 25°C and detection wavelength of 280 nm. The relative standard deviations of migration time ranged from 0.2 to 0.7% and the peak area ranged from 1.5 to 3.7% for the seven analytes, indicating the good repeatability of the proposed method. The method was extensively validated by evaluating the linearity ( R 2 ≥ 0.9992), limits of detection (0.14–0.36 μg/mL), limits of quantification (0.47–1.19 μg/mL), and recovery (96.0–102.6%). Under the optimum conditions, samples of Danshen and related medicinal plants were analyzed using the developed method with high separation efficiency.
研究领域:
药物分析
·
植物化学
·
电泳技术
·
质量控制
·
天然产物研究
✓ 已验证
DOI
高影响因子
BIOORGANIC CHEMISTRY
·
2020
·
IF 4.831
Ibrahim Khalifa,Du Xia,Kunal Dutta,Jinmeng Peng,Yangyang Jia,Chunmei Li
Advanced glycation end-products (AGEs), which instigate many disorders, are mostly mediated by dicarbonyl rearrangements. We studied the corresponding mechanisms of the anti-glycation effects of two anthocyanins purified from mulberry fruits, namely cyanidin 3-glucoside (C3G) and cyanidin 3-rutinoside (C3R), on glycated β-lactoglobulins (β-Lg). Both mulberry anthocyanins (MAs) inhibited the AGEs-formation in a dose-dependent manner, but the effect of C3R was significantly stronger than that of C3G (p < 0.05). MAs inhibited AGEs-formation by selectively trapping dicarbonyls, especially glyoxal. The UPLC-ESI-Q-TOF-MS results characterized that C3R formed mono- and di-glyoxal adducts, where C3G only created di-glyoxal adducts. Additionally, C3R could directly interact with some of the glycation sites of β-Lg. Overall, GO-trapping and β-Lg-MAs covalent/noncovalent binding are disclosed as the key mechanisms of the anti-AGEs activity of MAs on β-Lg, which could be valorised as effectual AGEs inhibitors in proteins-rich matrices.
研究领域:
食品科学
·
生物化学
✓ 已验证
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2024
·
IF 5.3
Wen-luan Xie,Bin Hu,Xiao Yang,Ji Liu,Zhi-mo Fang,Kai Li,Yang-wen Wu,Bing Zhang,Qiang Lu
Phosphoric acid is an effective and widely used catalyst for biomass pyrolysis, with significant catalytic impact on the pyrolytic reactions and product distribution. However, its fundamental catalytic mechanism in lignin pyrolysis remains unclear. In this work, we proposed and investigated three possible H 3 PO 4 -assisted pyrolysis mechanisms, i.e., hydrogen-bond-induced decomposition, phosphoric-acid-assisted hydrogen transfer (H 3 PO 4 -AHT), and phosphorolysis, and carefully discussed them through theoretical calculations, electronic structure analyses, catalytic pyrolysis experiments using the β -O-4 linked lignin model. The results indicated that the H 3 PO 4 -AHT mechanism played a dominant role in lignin catalytic pyrolysis, superior to the other two mechanisms. The phosphoric acid molecule could take advantage of its unsaturated P = O and saturated P −OH groups for hydrogen donation and acceptance in concerted H 3 PO 4 -AHT reactions. Alternatively, it could also participate in concerted intermolecular hydrogen transfer with the active hydroxyl group as a mediator. The C β −O bond cleavage could be significantly enhanced by effectively reducing the tension of the transition state ring, leading to the generation of more phenol and styrene in pyrolysis experiments. Due to the inhibition of hydrogen abstraction, C α −C β breakage of β -O-4 linkage, side chain removal of primary products, etc., the formation of other products in phosphoric acid catalytic pyrolysis of β -O-4 linked lignin was restrained. This H 3 PO 4 -AHT catalytic mechanism was also confirmed to be conductive to tautomerism, elimination, dehydration, α -O-4 linkage fracture, β -1 linkage fracture, and other important decomposition reactions in lignin pyrolysis. The understanding of these mechanisms provides valuable insights into the role of phosphoric acid in lignin pyrolysis and may guide the development of effective biomass catalytic conversion methods.
研究领域:
化学工程
·
生物质能
·
催化科学
✓ 已验证
DOI
高影响因子
Laser & Photonics Reviews
·
2021
·Vol. 15
·期 11
·2100317
·
IF 13.138
Xiangming Yue,Ju Xu,Hang Lin,Shisheng Lin,Renfu Li,Bo Wang,Qiugui Huang,Pengfei Wang,Ping Sui,Yao Cheng,Yuansheng Wang
The green-emissive laser phosphor is urgently demanded for projection displays to compensate the “Green Gap.” Herein, the well-known β-SiAlON:Eu 2+ with admirable luminescent feature is incorporated into robust silicate glass matrix, cosintered on sapphire plate, and then constructed into “phosphor wheel,” succeeding in retaining excellent green-emissive performance and meanwhile relieving the luminescence droop at high pumping density of blue laser. Probing the local effect of laser–matter interaction reveals that the luminescence saturation is majorly determined by thermal quenching, but the influence of intensity quenching cannot be ignored. Systematical works are performed to optimize glass composition, cosintering procedure, sample parameters, and optical path, turning out the maximal quantum efficiency of 60%, thermal conductivity of 9.5 W m −1 K −1 , and high saturation threshold far beyond 22 W mm −2 . In a proof-of-concept experiment, accompanied with red laser diode, the constructed light engine yields a high brightness with luminous flux of 1310 lm (luminance of 880 Mcd m −2 ), a low étendue of ≈1.5 mm 2 , and a wide color gamut of 112.5% National Television System Committee (NTSC), demonstrating the composite material as an efficient laser-driven color converter for projection displays.
研究领域:
材料科学
·
光学工程
·
显示技术
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Xiaoyu Zhu,Chen Cheng,Xingao Qin,Ying Wang
Per- and polyfluoroalkyl substances (PFAS) have raised significant concerns; however, their accurate detection in aqueous environments remains a major challenge. In this study, a host-guest molecularly imprinted polymer-based electrochemical sensor with enhanced antifouling properties were developed using β-cyclodextrin embedded with methylene blue (βCD-MB MIP). This sensor demonstrated sensitive and selective quantification of perfluorooctanoic acid (PFOA) in real water samples. The βCD-MB MIP was fabricated by electro-polymerizing βCD and MB in the presence of the target molecule, PFOA, where βCD served as the functional monomer and MB as the signaling probe. The incorporation of βCD endowed the MIP with a stable hydration layer, promoting hydrophilicity and inhibiting fouling, while ensuring effective electron transfer from MB, resulting in significant current responses and outstanding antifouling performance. This sensor exhibits excellent sensing capabilities towards PFOA with a detection limit of 1.57 pg mL −1 , covering a wide concentration range from 4.14 ng mL −1 to 41.4 mg mL −1 . It also displayed high selectivity for PFOA with an imprint factor of 6.5, which is five to seven times higher than that of other perfluorinated analogs. This study introduces an innovative platform for the rapid quantification of PFAS using redox-active MIPs and sets the groundwork for developing integrated sensors for continuous PFAS monitoring in water.
研究领域:
环境科学
·
电化学传感器
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2022
·
IF 4.601
Xiangqiong He,Adeel Ahmed,Shuaibing Guo,Chuankui Kang,Youqing Shen,Hailin Cong,Bing Yu
Recently, the design and development of efficient chiral stationary phases is still the core and goal of chiral chromatography. In order to quickly separate chiral drugs, we designed and prepared an environmentally friendly small particle chiral stationary phase: p-methylphenylurea-β-cyclodextrin chiral stationary phase (SiO 2 @PMPU-β-CD). Firstly, p-methylphenylurea-β-cyclodextrin (PMPU-β-CD) was connected to the surface of mesoporous silica microspheres by diazoresin (DR) to prepare a SiO 2 @PMPU-β-CD. In reverse elution mode, the column temperature was set at 25 °C, the flow rate was 0.2 mL/min, and ACN H 2 O (v/ v = 70:30) was used as the elution condition of the mobile phase. The enantiomers of chlorpheniramine maleate, 2-phenylcyclohexanone, and promethazine were separated within 5 min. In addition, the addition of TEAA buffer to the mobile phase improved the enantiomer resolution of chlorpheniramine maleate from 1.03 to 5.69. The experimental results show that the SiO 2 @PMPU-β-CD column can be used for the separation of appellant chiral drugs with good repeatability, and the use of DR instead of silane coupling agent has the advantages of being non-toxic, environmentally protected, and easy to operate, which is of great significance for the development of chiral stationary phase.
研究领域:
色谱学
·
药物化学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
Food Packaging and Shelf Life
·
2021
·
IF 6.429
Changzhu Li,Wenqing Chen,Subramanian Siva,Haiying Cui,Lin Lin
To develop a novel food packaging material, hydroxypropyl-β-cyclodextrin (HP-β-CD) with good water solubility was used to encapsulate cinnamaldehyde (CA). The prepared CA/HP-β-CD inclusion complex (CA/HP-β-CD-IC) was further embedded into the nanofibers, which were composed of phospholipid and poly (ethylene oxide). FTIR and molecular structure modeling indicated that CA was encapsulated in HP-β-CD most probably by directly inserting the phenyl of CA into the cavity of HP-β-CD. Subsequently, the preferable mechanical properties with the uniform diameter distribution of the mat of nanofibers were realized. Meanwhile, the thermal stability of CA was further improved after being embedded into HP-β-CD and the mat of nanofibers. For the application on fresh-cut cucumber, the mat of nanofibers encapsulated with CA/HP-β-CD-IC exhibited antibacterial activity against Listeria monocytogenes at 4 °C and 25 °C for 4 days, without significant effect on the sensory indicators of fresh-cut cucumber. Thus, the mat of nanofibers encapsulated with CA/HP-β-CD-IC could be a promising and practical food packaging material.
研究领域:
食品科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED TOXICOLOGY
·
2025
·
IF 2.8
Chenxi Yan,Guilan Li,Lian Huang,Zhaohui Zhang
Beryllium (Be) is a recognised environmental toxicant associated with pulmonary fibrosis. Epithelial–mesenchymal transition (EMT), a critical process in cell phenotype conversion, plays a key role in its pathophysiology. Methyltransferase-like 3 (METTL3), a major N6-methyladenosine methyltransferase, regulates gene expression and cellular functions. However, its role in Be-induced EMT remains unclear. In this study, human bronchial epithelial cell line (16HBE cells) were exposed to varying concentrations of beryllium sulphate (BeSO 4 ) to assess changes in METTL3 expression. METTL3 overexpression vectors were constructed, and quantitative reverse transcription-polymerase chain reaction, western blotting and immunofluorescence were used to detect METTL3, EMT markers and Wingless/Integrated (Wnt)/β-catenin pathway proteins. The Wnt/β-catenin pathway inhibitor ICG-001 was also employed to explore the role of the Wnt/β-catenin pathway in BeSO 4 -induced EMT. The study demonstrated that BeSO 4 suppressed METTL3 expression, induced EMT and activated the Wnt/β-catenin pathway in 16HBE cells. Both METTL3 overexpression and ICG-001 pretreatment mitigated BeSO 4 -induced EMT and Wnt/β-catenin pathway activation. These findings suggest that METTL3 inhibits BeSO 4 -induced EMT by suppressing the Wnt/β-catenin pathway, offering novel mechanistic insights into beryllium toxicity and a potential therapeutic target for Be-related pulmonary fibrosis.
研究领域:
细胞生物学
·
毒理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）