JOURNAL OF HETEROCYCLIC CHEMISTRY
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2014
·Vol. 51
·期 4
·1094-1099
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IF 0.873
Guangfan Han,Jiawei Du,Lizhuang Chen,Lijun Zhao
A series of 2-amino-7-methoxy-4-aryl-4 H -chromene-3-carbonitrile compounds 2 were obtained by condensation of 3-methoxyphenol with β-dicyanostyrenes 1 in absolute ethanol containing piperidine. The intermediate enamines 3 were prepared by compounds 2 with 5-substituted-1,3-cyclohexanedione using p -toluenesuflonic acid (TsOH) as catalyst. The title compounds 11-amino-3-methoxy-8-substituted-12-aryl-8,9-dihydro-7 H -chromeno[2,3- b ]quinolin-10(12 H )-one 4 were synthesized by cyclization of the intermediate enamines 3 in THF with K 2 CO 3 /Cu 2 Cl 2 as catalyst. The structures of all compounds were characterized by elemental analysis, IR, MS, and 1 H NMR spectra. The crystal structure of compound 4i was determined by single-crystal X-ray diffraction analysis.
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ANALYTICAL SCIENCES
·
2014
·Vol. 30
·期 4
·489-494
·
IF 1.403
Xiu-Fang YAN,Hai-Long WU,Xiang-Dong QING,Yan-Mei SUN,Ru-Qin YU
In this work, a simple and practicable method that combines excitation-emission matrix (EEMs) fluorescence with a second-order calibration method based on parallel factor analysis-alternative least-squares (PARAFAC-ALS) algorithm was developed for the direct interference-free determination of indole-3-acetic acid (IAA) in two real systems, coconut water (CW) and coconut milk (CM). Although the excitation and emission profiles of IAA heavily overlapped with that of unknown interferents in the complex real systems, the actual contents and satisfactory recoveries were still obtained successfully. The contents of IAA in CW and CM were 10.8 ± 0.3 and 4.9 ± 0.2 μg mL−1, respectively, which were consistent with those reported by LC-MS/MS assays in the reference material. The average spike recoveries of IAA in the validation set based on CW and CM were 102.1 ± 3.2 and 98.0 ± 1.9%, respectively. In addition, routine experiments were performed for establishing the validity of the assay to internationally accepted criteria.
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Polymer Chemistry
·
2013
·Vol. 4
·期 17
·4588-4595
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IF 5.231
Zong-Quan Wu,Deng-Feng Liu,Ying Wang,Na Liu,Jun Yin,Yuan-Yuan Zhu,Long-Zhen Qiu,Yun-Sheng Ding
A range of poly(3-hexylthiophene)-b-poly(quinoxaline-2,3-diyl) rod–rod diblock copolymers was synthesized in one pot via sequential monomer addition with a Ni(II) complex as a single catalyst at room temperature. The block copolymerization was proved to proceed in a living/controlled chain-extension manner, affording well-defined poly(3-hexylthiophene)-b-poly(quinoxaline-2,3-diyl) block copolymers with controlled molecular weights, narrow molecular weight distributions, and tunable compositions. The synthesized block copolymer was found to self-assemble into well-defined vesicle supramolecular structures in mixed solvents of chloroform and methanol. The assembly in solution induced unique light emissions with the light emission color varying from red to purple and blue depending on solvents used.
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APPLIED SURFACE SCIENCE
·
2013
·
IF 2.112
Yongbing Yuan,Hongling Chen
The chemical modification of calcined kaolinite particle surface via stepwise method using 3-glycidoxypropyltrimethoxysilane (GPS) and dodecylamine was investigated. Silylation of kaolinite particles was controlled by varying the amount of GPS under almost anhydrous condition. FT-IR and thermal analysis indicated that silylation monolayer coverage on kaolinite particle surface increased with the increasing of the amount of additive GPS, reaching a maximum value of 8.81 μmol/m 2 when the mass ratio of kaolinite to GPS was up to 1:1. Further modification of the silylated kaolinite particle surfaces was accomplished using the modifier synthesized by the ring-open reaction of GPS and dodecylamine to form multilayer branches at the presence of H 2 O (pH = 12). The final modified kaolinite particle surfaces contained both hydrophobic long alkyl chains and hydrophilic groups, which were advantageous to homogeneous dispersion in low polar as well as polar solvents, respectively. Digital photographs and TEM images revealed that the final modified kaolinite particles were homogeneously dispersed in acetone, dioxane, ethanol, and THF, even better than raw kaolinite dispersed in ethanol. Meanwhile, the dispersion properties in low polar solvents such as xylene, cyclohexane and petroleum ether were also acceptable, and the aggregate particle size was near to primary particle size of raw kaolinite, or just a bit larger, increasing from 1.25 to 1.75–2.00 μm.
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INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2013
·
IF 2.206
Hong Xu,Fangfang Tong,Jian Yu,Lixiong Wen,Jun Zhang,Jiasong He
Poly(methyl methacrylate) (PMMA) and sodium montmorillonite (Na-MMT) were melt-blended with 1-dodecyl-3-methylimidazolium hexafluorophosphate (C12mimPF6) to prepare nanocomposites containing well-dispersed MMT layers in nanoscale and freely existed excess C12mimPF6. A synergistic effect of MMT and C12mimPF6 on the foaming behavior of nanocomposites was revealed in this study. At the mild conditions of 17 MPa and 35 °C, neat PMMA and PMMA/C12mimPF6 and PMMA/Na-MMT samples were not foamed, while cells were induced in nanocomposites containing a certain amount of free C12mimPF6. At 25 MPa/90 °C, foamed nanocomposites exhibited higher nucleation efficiency and cell density, and smaller cell sizes with narrower size distribution than that of neat PMMA and those binary samples. The results indicated that the MMT nanoparticles produced heterogeneous nucleation, and increased the modulus of polymer matrix to depress cell coalescence. The presence of free C12mimPF6 decreased the energy barrier for cell nucleation and facilitated the dispersion of MMT nanoparticles via in situ organic modification.
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INTERNATIONAL IMMUNOPHARMACOLOGY
·
2024
·
IF 4.8
Shuyan Liu,Shunqing Zhou,Bo Wang,Zanhui Jia
Curcumin (CUR) exhibits potential inhibitory effects on tumor growth; however, its hydrophobicity and instability limit its clinical applications. In the present study, we developed CUR nanoparticles (CUR-NPs) and evaluated their biochemical characteristics. Cell uptake and proliferation were assessed using scratch and Transwell assays, respectively. Western blotting was performed to investigate the expression levels of proteins related to the NF-κB/PRL-3 signaling pathway, inflammatory response, cell proliferation, and cell migration in SKOV3 cells. Our findings showed that the blank vector was not cytotoxic to cells, allowing us to disregard any effects caused by the vector itself. CUR-NPs exhibited concentration- and time-dependent inhibitory effects on cell proliferation, surpassing those of CUR alone. Increasing the concentration of CUR-NPs resulted in a reduced cell scratch-healing ability and lower chamber migration capacity. Compared to the control group, expression levels of proteins associated with NF-κB/PRL-3 signaling pathway, inflammatory response (TNF-α and IL-6), cell proliferation (cyclin E1 and cyclin A1), as well as cell migration (N-cadherin and vimentin) were significantly elevated in the lipopolysaccharide (LPS) stimulation and NF-κB p65 overexpression groups. Conversely, E-cadherin expression was significantly decreased under these conditions. However, treatment with high concentrations of CUR-NPs effectively reversed these changes. These results highlight the significant ability of CUR-NPs to inhibit human ovarian cancer cell proliferation and migration, while suppressing inflammatory responses through the regulation of the NF-κB/PRL-3 signaling pathway.
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BIOORGANIC CHEMISTRY
·
2024
·
IF 4.5
Muhammad Waheed Iqbal,Xinrui Tang,Tahreem Riaz,Shahid Mahmood,Yufei Zhang,Mei Zhao,Junhua Yun,Jia Li,Xianghui Qi
6-Deoxy- l -sorbose (6-DLS) is an imperative rare sugar employed in food, agriculture, pharmaceutical and cosmetic industeries. However, it is a synthetic and very expensive rare sugars, previously synthesized by chemo-enzymatic methods through a long chain of chemical processes. Recently, enzymatic synthesis of rare sugars has attracted a lot of attention due to its advantages over synthetic methods. In this work, a promising approach for the synthesis of 6-DLS from an inexpensive sugar l -fucose was identified. The genes for l -fucose isomerase from Paenibacillus rhizosphaerae (Pr-LFI) and genes for d -tagatose-3-epimerase from Caballeronia fortuita (Cf-DTE) have been used for cloning and co-expression in Escherichia coli , developed a recombinant plasmid harboring pANY1-Pr-LFI/Cf-DTE vector. The recombinant co-expression system exhibited an optimum activity at 50 °C of temperature and pH 6.5 in the presence of Co 2+ metal ion which inflated the catalytic activity by 6.8 folds as compared to control group with no metal ions. The recombinant co-expressed system was stable up to more than 50 % relative activity after 12 h and revealed a melting temperature (T m ) of 63.38 °C exhibiting half-life of 13.17 h at 50 °C. The co-expression system exhibited, 4.93, 11.41 and 16.21 g/L of 6-DLS production from initial l -fucose concentration of 30, 70 and 100 g/L, which equates to conversion yield of 16.44 %, 16.30 % and 16.21 % respectively. Generally, this study offers a promising strategy for the biological production of 6-DLS from an inexpensive substrate l -fucose in slightly acidic conditions with the aid of co-expression system harboring Pr-LFI and CF-DTE genes.
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PROCEEDINGS OF THE COMBUSTION INSTITUTE
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2024
·
IF 5.3
Qilong Fang,Jun Fang,Yi Zhang,Jianguo Zhang,Tianyou Lian,Wei Li,Yuyang Li
Oxymethylene ethers (OMEs) have received great attention due to their carbon-neutral nature and advantageous properties as alternative transportation fuels or fuel additives. Previous studies focused on the combustion of linear OMEs with the chemical formula of CH 3 O(CH 2 O) m CH 3 ( m ≥ 0), while a deep understanding of the combustion of branched OMEs with the chemical formula of CH 3 OCH 3- n (OCH 3 ) n (0 ≤ n ≤ 3) is still absent. In this work, the flow reactor pyrolysis of dimethoxymethane (DMM, n = 1), trimethoxymethane (TMM, n = 2), and tetramethoxymethane (TeMM, n = 3) is investigated using gas chromatography, with special attention given to the multi-sidechain effects on the pyrolysis chemistry. A pyrolysis model of branched OMEs is developed and validated against the new pyrolysis data. Modeling analysis is performed to provide insights into the pyrolysis chemistry of the three branched OMEs and the multi-sidechain effects. Unimolecular decomposition and H-abstraction reactions are found to be two major types of fuel decomposition pathways, with the former dominating TMM decomposition, the latter dominating DMM decomposition, and both contributing almost equally to TeMM decomposition. Sensitivity analysis shows that C O bond dissociation is the most sensitive reaction to fuel decomposition in DMM pyrolysis, while methanol elimination is the most sensitive reaction in TMM and TeMM pyrolysis. Among the three fuels, DMM has the lowest pyrolysis reactivity and produces the least abundant methanol. In contrast, TMM is observed with the highest pyrolysis reactivity and produces the most abundant methanol. Theoretical calculations reveal that TMM and DMM have the lowest and highest energy barriers of methanol elimination reactions, which determines the order of their pyrolysis reactivities and methanol formation trends. As a result, DMM pyrolysis occurs at higher temperature regions where the C O bond dissociation and H-abstraction reactions are preferred, while TMM pyrolysis occurs at lower temperature region where methanol elimination dominates.
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Food Bioscience
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2024
·
IF 4.8
Haoyue Ning,Lixin Lu,Yuemei Zhang
To achieve long-term effective protection of food by continuously controlling the release of active substances in an active film, IRMOF-3 was post-synthetic modified with benzoic acid (BA) to obtain BA-IRMOF-3. This modification enhanced the loading capacity of carvacrol (CA) and slowed down its release rate. Research on IRMOF-3 synthesis has found that increasing the proportion of metal nodes can improve its crystallinity. The post-synthesis modification of IRMOF-3 through amide reaction successfully enhanced the binding energy with CA from −5.1 kcal/mol to −6 kcal/mol, resulting in an improved CA loading rate of 28.62% ± 0.15% and delayed release. Furthermore, the BA-IRMOF-3/CA assembly was added to the sodium alginate matrix to prepare the active film BMC@SA, which improved the mechanical and physical properties of the film. The release and antibacterial/antioxidant properties were investigated. The results demonstrated that the active film BMC@SA exhibited significant sustained-release properties and antibacterial/antioxidant activities, reducing the growth of E. coli and S. aureus by 61.95% and 49.33% respectively. In refrigerated pork experiments, the film BMC@SA slowed down the color, weight, pH changes and inhibited microbial growth of fresh pork effectively, and extended the shelf life of pork from 6 d to 12 d, which demonstrated the potential application of active film BMC@SA in food preservation.
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INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2024
·Vol. 25
·期 3
·1708
·
IF 4.9
Ling Chen,Yueying Wang,Lei Zhu,Yong Min,Yuxi Tian,Yan Gong,Xiaoyan Liu
Root knot nematodes cause serious damage to global agricultural production annually. Given that traditional chemical fumigant nematicides are harmful to non-target organisms and the environment, the development of biocontrol strategies has attracted significant attention in recent years. In this study, it was found that theBacillus thuringiensisBerliner strain NBIN-863 exhibits strong fumigant nematicidal activity and has a high attraction effect onMeloidogyne incognita(Kofoid and White) Chitwood. Four volatile organic compounds (VOCs) produced by NBIN-863 were identified using solid-phase microextraction and gas chromatography–mass spectrometry. The nematicidal activity of four VOCs, namely,N-methylformamide, propenamide, 3-(methylthio)propionic acid, and phenylmalonic acid, was detected. Among these compounds, 3-(methylthio)propionic acid exhibited the highest direct contact nematicidal activity againstM. incognita, with an LC50 value of 6.27 μg/mL at 24 h. In the fumigant bioassay, the mortality rate ofM. incognitatreated with 1 mg/mL of 3-(methylthio)propionic acid for 24 h increased to 69.93%. Furthermore, 3-(methylthio)propionic acid also exhibited an inhibitory effect on the egg-hatching ofM. incognita. Using chemotaxis assays, it was determined that 3-(methylthio)propionic acid was highly attractive toM. incognita. In pot experiments, the application of 3-(methylthio)propionic acid resulted in a reduction in gall numbers, decreasing the number of galls per gram of tomato root from 97.58 to 6.97. Additionally, the root length and plant height of the treated plants showed significant increases in comparison with the control group. The current study suggests that 3-(methylthio)propionic acid is a novel nematicidal virulence factor ofB. thuringiensis. Our research provides evidence for the potential use of NBIN-863 or its VOCs in biocontrol against root knot nematodes.
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Food Bioscience
·
2024
·
IF 4.8
Danyang Liu,Yiming Song,Xinyi Chen,Jianhua Xie,Yi Chen,Xiaobo Hu,Jiayan Xie,Qiang Yu
Previous studies have shown that bound polyphenols from tea residue dietary fiber (TBP) were novel natural food ingredient with hypoglycemic activity, but the protective effects against aging have not been fully explored. This study investigated the potential of TBP to alleviate aging in Caenorhabditis elegans induced by 3-monochloropropane-1,2-diol (3-MCPD) and elucidated the underlying mechanisms through transcriptomic and metabolomic analyses. The results demonstrated that TBP markedly prolonged the lifespan of the nematodes, improved body morphology and locomotion, and effectively reduced reactive oxygen species and lipofuscin accumulation, while enhancing antioxidant defenses. Transcriptomic and metabolomic analyses further highlighted the critical role of the Insulin/Insulin-like Growth Factor 1 (insulin/IGF-1) signaling pathway in lifespan extension, with validation provided through gene expression and fluorescent mutants. These findings underscored the significant potential of TBP to counteract the adverse effects of 3-MCPD and extend lifespan, thereby providing a solid theoretical foundation for developing health products and exploring novel applications.
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HEREDITAS
·
2024
·Vol. 161
·期 1
·1-17
·
IF 2.1
Zheng Jianxiu,Wang Liyan,Liu Ahui,Shen Haofei,Wang Bin,Jiang Yanbiao,Jing Panpan,Guan Defeng,Yu Liulin,Zhang Xuehong
Background Indole-3-acetic acid (IAA), an indole analog produced by intestinal microorganisms metabolizing tryptophan, has anti-inflammatory and antioxidant properties and thus has potential applications in ovarian protection, although the exact mechanism is unknown. The present study preliminarily investigated the pharmacological mechanism of IAA in alleviating diminished ovarian reserve (DOR) by network pharmacology and molecular docking. Methods Relevant target proteins of IAA were searched in SwissTargetPrediction, PharmMapper, TargetNet, BATMAN-TCM, and SuperPred databases. The potential targets of DOR were obtained from GeneCards, DisGenet, OMIM, and Drugbank databases. Both common targets were then imported into the String website to construct a PPI network, and these targets were analyzed for GO and KEGG enrichment. Finally, we utilized molecular docking to validate the possible binding conformations between IAA and the candidate targets. We used in vitro experiments to preliminarily investigate the effects of IAA on DOR. Results We obtained 88 potential targets for IAA and DOR interaction. We received 16 pivotal targets by constructed protein interaction screening. KEGG enrichment analysis mainly included the AGE-RAGE signaling pathway, IL-17 signaling pathway, Chemical carcinogenesis—reactive oxygen species in diabetic complications, etc. GO functional analysis showed that IAA treatment of DOR may involve biological processes such as response to external stimuli, hypoxia, gene expression, and regulation of enzyme activity. Molecular docking and in vitro experiments further revealed the potential effects of IAA on MMP2, TNF-α, AKT1, HSP90AA1, and NF-κ B. Conclusion We preliminarily revealed the potential protective effects of IAA against DOR through multiple targets and pathways, which provides a new research strategy for the molecular mechanism of IAA to alleviate DOR in the future. However, further studies need to demonstrate whether IAA can be used as a compound to prevent and treat DOR.
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