APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Xinlei Ji,Jia Kou,Gökalp Gözaydın,Xi Chen
Chitin biorefinery offers a unique opportunity to sustainably produce highly-valued organonitrogen compounds such as the versatile pharmaceutical precursor 3-acetamido-5-acetylfuran (3A5AF), bypassing the Haber process and mitigating the consumption of fossil feedstocks. However, the reported protocols engaged large quantities of toxic organic solvents and required harsh conditions. In this work, a highly efficient catalytic system has been developed in the nontoxic, biobased γ-valerolactone (GVL) solvent under relatively mild conditions. 3A5AF was selectively obtained with an unprecedent yield of 75.3% at 140 °C for 2 h by adding NH 4 SCN and HCl. The high yielding was exclusively promoted by a dissolution-dehydration effect. Based on the UPLC-TOF-MS and NMR analyses, the presence of NH 4 SCN has induced a very rapid NAG conversion possibly by coordinating with the acetamido group and the hydroxyl groups, and the 3A5AF product was obtained in a subsequent dehydration pathway from NAG with the Chromogen I and Chromogen III as the intermediates.
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INTERNATIONAL IMMUNOPHARMACOLOGY
·
2019
·
IF 3.361
Yutong He,Zijing Xia,Deqing Yu,Jiankang Wang,Liang Jin,Demin Huang,Xiaoli Ye,Xuegang Li,Baoshun Zhang
Acute liver failure (ALF) is a distinct clinical syndrome with high mortality and characterized by metabolic derangements, neurological complication , and multiple failures. Flavonoids exert great biological properties on anti-oxidation, anti-inflammation, and anti-apoptosis. After lipopolysaccharide (LPS)/ d -galactosamine ( d -GalN) administration, five flavonoids inhibited oxidative activities with reducing nitric oxide synthase (iNOS), malondialdehyde (MDA), and improving catalase (CAT), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), nuclear factor erythroid-derived 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). They reduced the serum levels of alanine and aspartate aminotransferase (ALT, AST) and pro-inflammatory cytokines, prevented the phosphorylation of IKK, IκBα, and NF-κB/p65 in the NF-κB signaling pathway . Additionally five flavonoids inhibited hepatocyte apoptosis through increasing Bcl-2/Bax ratio and suppressing the Caspase family proteins. Chrysin , luteolin , apigenin , hesperetin and 3′, 4′-dimethoxy hesperetin have apparently hepato-protective effects against ALF induced by LPS/ d -GalN. The study found, the C2 C3 double bond at A ring, and the hydroxyl group of C3′ or C4′ at B ring increased the protective activities, however, the effect of hydroxymethylation at C3′ and C4′ was reversed. In addition, apigenin has good hepatoprotective effects and potential as a promising therapeutic agent for ALF in clinical application.
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ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Mengjie Wu,Hui Ma,Zhongyi Ma,Yufang Jin,Chunyan Chen,Xiaoya Guo,Yan Qiao,Christian Marcus Pedersen,Xianglin Hou,Yingxiong Wang
Deep eutectic solvents (DESs) exhibit similar physicochemical properties to the ionic liquids. They are inexpensive, renewable, nontoxic, and environmentally benign solvents and have gradually attracted attention in several fields, for example, biorefinery. Here choline chloride-based DESs have been used as solvents and catalysts for the preparation of deoxyfructosazine (DOF) through a self-condensation reaction of d-glucosamine (GlcNH2). The catalytic performances of a “green cocatalyst”, amino acids, and the reaction mechanism were also studied. The results displayed that choline chloride/urea was capable to convert GlcNH2 efficiently, with a 13.5% yield of DOF at low temperature and with a short reaction time (100 °C, 150 min). Among the screened amino acids, arginine showed the highest activity and gave the highest yield of DOF (30.1%) under the optimized reaction conditions. Nuclear magnetic resonance (NMR) studies revealed a strong hydrogen bond interaction between GlcNH2 and arginine. Moreover, a detectable intermediate, namely dihydrofructosazine, in the condensation of GlcNH2 to DOF/fructosazine (FZ) was captured by in situ NMR technique.
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TOXICOLOGY LETTERS
·
2024
·
IF 2.9
Yingxin Pang,Xiaoqi Tao,Zongmin Qin,Muran Jiang,Erqun Song,Yang Song
This work investigated the influence of surface chirality on cellular internalization, cytotoxicity, and tissue distribution of silver nanoparticles (AgNPs). D-cysteine and L-cysteine are chiral forms of the amino acid cysteine. These enantiomers exhibit distinct spatial arrangements, with D-cysteine having a different configuration from L-cysteine. This structural dissimilarity can lead to variations in how these forms interact with biological systems, potentially impacting their cytotoxic responses. Four distinct types of AgNPs were synthesized, each possessing a unique surface coating: pristine AgNPs (pAgNPs), L-cysteine coated AgNPs (AgNPs@L-Cys), D-cysteine coated AgNPs (AgNPs@D-Cys), and racemic AgNPs coated with both L-Cys and D-Cys (AgNPs@L/D-Cys). We found chiral-dependent cytotoxicity of AgNPs on J774A.1 cells. Specifically, AgNPs@L-Cys exhibited the highest toxicity, and AgNPs@D-Cys exhibited the lowest toxicity. Meanwhile, the cellular uptake of the AgNPs correlated nicely with their cytotoxicity, with AgNPs@L-Cys being internalized to the greatest extent while AgNPs@D-Cys displays the least internalization. Scavenger receptors and clathrin predominantly mediate the cellular internalization of these AgNPs. Strikingly, the dissimilar cellular internalization and cytotoxicity of AgNPs with different chirality were eliminated upon protein corona coverage. Notably, following intravenous injection in mice, these four types of AgNPs showed similar patterns among various organs due to the inevitable protein adsorption in the bloodstream. These findings underscored the pivotal role of surface chirality in governing the biological interactions and toxicity of AgNPs.
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Journal of Physical Chemistry C
·
2015
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IF 4.772
Yongxin Tao,Xiaogang Gu,Linhong Deng,Yong Qin,Huaiguo Xue,Yong Kong
We report a Cu2+-modified β-cyclodextrin, Cu2-β-CD, that was self-assembled on poly(l-glutamic acid) (P-l-Glu) for chiral recognition of d-tryptophan (d-Trp). Cu2+ formed binuclear hydroxy-bridge (Cu(OH)2Cu) at the wider opening of the cavity of β-CD and acted as a cap to prevent high-energy water molecules from being released while forcing Trp isomers to enter through its narrower opening. Because H-bonds were favored to form between the high-energy water molecules and the amino groups of d-Trp inside the cavity of β-CD, d-Trp was thus recognized. The recognition capability of the Cu2-β-CD appeared to depend on the way the Cu2-β-CD self-assembled onto P-l-Glu, preferring via H-bonds rather than via electrostatic interactions, because electrostatic interactions between P-l-Glu and Cu(OH)2Cu could alter the configuration of the Cu2-β-CD cavity, resulting in weakened H-bonds between high-energy water molecules and d-Trp.
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APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Songlin Chen,Zhihao Shen,Shuming Wen,Guang Han,Qicheng Feng
Flotation separation of Cu–Fe sulfide minerals typically necessitate the addition of substantial quantities of lime to depress pyrite flotation. Because lime can harm the environment, there is an urgent need to develop novel environmentally friendly depressants that are non-toxic and biodegradable. In this study, we investigated an environmentally friendly pyrite depressant containing amino and carboxyl groups, namely D-arginine (DA). The effect of DA on the surface hydrophobicity of Cu–Fe sulfide minerals and thus collector adsorption was investigated by analyzing zeta potentials, adsorption capacities, and contact angles. Additionally, changes in the surface properties of the minerals induced by DA were examined using X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), and atomic force microscopy (AFM). Flotation tests revealed that 2 × 10 –4 mol/L DA reduced the flotation recovery of pyrite to 9.96 % at low alkalinity while leaving chalcopyrite recovery unchanged. The results of mineral surface analysis indicated that DA exhibited significantly stronger adsorption on the pyrite surface than on the chalcopyrite surface. Furthermore, DA effectively reduced the adsorption of the collector on the surface of pyrite, thereby weakening pyrite floatability at low alkalinity. Therefore, DA is a promising alternative depressant for the flotation separation of chalcopyrite from pyrite.
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CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Ding-Ming Xue,Yi-Jun Zhang,Jing-Wen Chen,Hao Yang,Rui-Jie Xie,Shi-Chao Qi,Yuan-Qing Bu,Fei Liu,Hou-Hu Zhang,Jacques Lalevée
Covalent organic frameworks (COFs), as a newly emerging kind of porous and crystalline materials, serve as an ideal template for hydrogen peroxide (H 2 O 2 ) photosynthesis. However, the vision of achieving high efficiency and selectivity in H 2 O 2 photosynthesis is greatly hindered by the large exciton binding energy and limited charge separation efficiency influenced by the molecular structure of the building blocks. Herein, we developed three newly designed COFs with a donor–acceptor (D-A) structure and incorporated regulatory units (fluorine, F, and methoxyl, OCH 3 ) in the D-A pathway through molecular engineering to optimize electronic structure, the availability of activate sites, charge kinetics and O 2 activation capacity. Due to electron-donating effect, OCH 3 -functionalization (NIES-COF-3) can strengthen the intramolecular electron transfer and interaction with O 2 . This results in a reduction of the energy barrier of the rate-determining step (*O 2 → *OOH) and excellent O 2 -to-H 2 O 2 photocatalytic activity under visible light irradiation, delivering an H 2 O 2 production rate of 3238.4 μmol g −1 h −1 and a high apparent quantum yield of 3.17 %. In addition, F-functionalization (NIES-COF-2) primarily reduces the band-gap energy and improve the O 2 adsorption capacity compared to unfunctionalized NIES-COF-1. This work unveils insight into the catalytic activity-optimization mechanism of molecular engineering in the D-A structure and provides important references for photocatalysts.
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Foods
·
2025
·Vol. 14
·期 9
·1538
·
IF 5.1
Zepeng Li,Runmin Wang,Xiantai Lai,Wenyi Liao,Runfeng Liao,Zhuohong Wu,Guoyan Zhang,Xianghui Qi
D-tagatose is a functional sweetener with glucose-regulating and prebiotic properties, but its bioproduction from D-galactose faces many limitations, particularly the high production costs. In particular, the current biosynthesis of D-tagatose suffers from thermal instability and the substrate selectivity issues of L-arabinose isomerase (L-AI) required to convert D-galactose into D-tagatose. In this study, recombinantEscherichia coliBW25113/pQE-80L-araAF118M/F279Iexpressing double mutant L-AI was immobilized to enhance its stability and reusability. The optimal conditions for whole-cell catalysis were 60 °C, pH 6.5, 5 mM Mn2+, and 20 h, with a yield of 55.2 g/L of D-tagatose. Immobilization with 3% sodium alginate and 2% CaCl2retained 90% of the production efficiency displayed by free cells. Notably, the immobilized cells exhibited enhanced heat resistance (60–70 °C) and operational stability, retaining 76% activity after five cycles. The D-tagatose production was further increased to 129.43 g/L by increasing the substrate concentration to 250 g/L. Compared to free cells, immobilized cells retained 83.6% of the initial yield up to 10 batches. This study presents a cost-effective and sustainable method for the production of D-tagatose using optimized whole-cell catalysis through immobilization, which paves the way to solve industrial challenges such as thermal instability and low substrate efficiency.
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ACS Nano
·
2025
·
IF 16
Xuyu Li,Qingfu Zhao,Xiaolin Feng,Pinyuan Cui,Jingjing Yu,Binyong Liang,Chao Liu,Ye Wang,Yiting Wu,Ruiqi Wang,Bo Hu,Yihan Lin,Lichong Zhu,Xuan Zhu,Ban Luo,Xiangliang Yang,Jun Hu
Immunoradiotherapy (iRT) has emerged as a promising strategy for liver hepatocellular carcinoma (LIHC) treatment to synergistically activate both localized antitumor immunity and systemic immune responses. However, radiation will aggravate LIHC hypoxia, resulting in an adenosine metabolism level elevation, which promotes the differentiation of T cells into terminally exhausted phenotypes and weakens the efficacy of immunotherapy. To overcome this challenge, we engineered a nanocatalytic probiotic-based radiation-metabolic modulator, in which Escherichia coli Nissle 1917 (EcN) was programmed to in situ synthesize gold–palladium bimetallic nanocatalysts (EcNcGP) via biodirected mineralization. Guided by lattice mismatch and interfacial strain engineering, engineered EcN orchestrates the epitaxial assembly of Au atoms on Pd nanoclusters, yielding a precisely strain-tuned heterostructure with a modulated d-band electronic structure. This architectural design optimizes oxygen intermediate adsorption–desorption kinetics and significantly enhances the catalytic efficiency. This design enables EcNcGP to exhibit robust catalase- and peroxidase-like activities, which effectively catalyze intratumoral H2O2 into O2 and hydroxyl radicals, intensifying radiation damage and alleviating tumor hypoxia to inhibit adenosine metabolism by downregulating the expression of ectonucleoside triphosphate diphosphate hydrolase 1 (CD39) and ecto-5′-nucleotidase (CD73). By blocking the binding of adenosine (ADO)–adenosine receptor A2A (ADORA2A) to inhibit the following cyclic adenosine monophosphate (cAMP)–protein kinase A (PKA)–phosphorylation of cAMP response element binding (pCREB) signaling transduction, radiation-induced T-cell exhaustion could be inhibited. Compared to stereotactic body radiotherapy (SBRT), the combination of EcNcGP with SBRT increased CD8+ T-cell infiltration by 99.8% and reduced PD-1hi-exhausted T cells by 63.9%. Integration with anti-PD-L1 therapy (αPD-L1) achieved complete tumor regression in 60% of the treated mice-bearing orthotopic hepatocellular carcinoma. These findings establish a paradigm-shifting strategy for reprogramming tumor-immune metabolic checkpoints using strain-engineered nanocatalytic probiotics, thereby enhancing iRT and overcoming radioresistance.
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CARBOHYDRATE RESEARCH
·
2011
·Vol. 346
·期 11
·1327-1332
·
IF 1.898
Jun Zhang,Lu Lin,Junhua Zhang,Jianbin Shi
Ru/MCM-41 catalyst prepared by an impregnation–formaldehyde reduction method showed higher catalytic activity and sorbitol selectivity than other catalysts in the hydrogenation of glucose. SEM and XRD indicated the partial surface properties of Ru/MCM-41. Moreover, Ru dispersion and Ru surface area of Ru/MCM-41 were determined by pulse chemisorption, and the result further proved that Ru/MCM-41 had higher catalytic activity. A catalyst recycling experiment demonstrated that Ru/MCM-41 was a better catalyst and it could be reused three or four times. A speculated mechanism was proposed to illustrate the detailed process of d -glucose hydrogenation to produce sorbitol.
研究领域:
催化化学
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化学工程
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绿色化学
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材料科学
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JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 21
·18307-18319
·
IF 2.22
Liu Xiongzhang,Luo Hui,Li Yingrui,Chen Fu,Wang Xian,Gong Rongzhou
Titanium boride (TiB 2 ) particles and fibers were synthesized by the carbothermal method with different calcination temperatures and time. Subsequently, the effects of calcination temperatures and time on microstructure and the yield of TiB 2 fibers were investigated. Further, the dielectric and microwave absorption (MA) properties of TiB 2 /paraffin composites within 2–18 GHz were discussed. As a result, the yield of TiB 2 fibers reached a maximum at 1400 °C for 180 min. The content of TiB 2 was directly proportional to permittivity. The sample containing 80 wt % TiB 2 particles and fibers indicated that the minimum reflection loss ( RL min ) attained − 46.5 dB at 11.6 GHz when the thickness was 1.45 mm and the effective absorption bandwidth (EAB) was 4.64 GHz ( RL <–10 dB) with the thickness of 1.25 mm. The related MA mechanisms were also discussed. The excellent stability, simple production procedure, thin absorbing layer, and wide EAB make TiB 2 become an ideal candidate for microwave absorbing materials applied in high temperatures.
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INTEGRATED FERROELECTRICS
·
2023
·
IF 0.7
Lu-Ping Chen,Zhen Zhang,Wang-Quan Zhang,Hai-Lin Cong,You-Qing Shen,Bing Yu
Malignant tumor is one of the most important causes of death in the world today. At present, the successful cure cases of tumor patients are mainly due to the timely treatment of tumors. Therefore, it has become one of the urgent problems for human beings to find tumors as soon as possible and how to completely eradicate them. The technology of simultaneous imaging and treatment through photoinitiation is a promising strategy to fight cancer. In the previous research, we developed a new small molecule p-QM2AF for photothermal therapy, but the low fluorescence efficiency (QY) in the NIR-II range made it necessary to modify it. In this paper, we obtained better imaging and photothermal conversion performance by grafting two 9- methylene nonadecanes onto the p-QM2AF sub-receptor.
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危险品化学品经营许可证（带存储）