CHEMICAL ENGINEERING JOURNAL
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2021
·
IF 13.273
Yingnan Liu,Yaqing Xiao,Minghui Shang,Yuting Zhuang,Li Wang
The method of monitoring the freshness of seafood is not satisfactory for ensuring food safety. Here, we develop a filter membrane-based smart fluorescent tag with excellent biogenic amine response, which can monitor the freshness of seafood in real time and visually. We use green fluorescent fluorescein as an indicator and red fluorescent carbon quantum dots (RQDs) with aggregation-induced emission property as an internal reference. After simple mixing, they are deposited on the commercial filter membrane by physical deposition method to prepare the fluorescent tag. When amine molecules are present, the molecular conformation of fluorescein changes and the fluorescence increases rapidly, while RQDs have no obvious response, thus achieving a clear fluorescence color response to biogenic amines. Under UV light of 254 nm and 365 nm, the fluorescent tag showed sensitive, rapid, and color-responsive to ammonia in a wide range of 250–2.5 × 10 4 ppm. To further verify the practical application potential, the fluorescent tag was used to monitor the freshness of shrimp and crab in situ in real time, and satisfactory results were achieved. More importantly, owing to the reversible conformational change of fluorescein, the fluorescent tag can be reused and manufactured at low cost, making it a more attractive platform for freshness monitoring in the field of food safety.
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Molecular Catalysis
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2021
·
IF 5.062
Wei Luo,Jiagui Hu,Jiapeng Lu,Huili Zhang,Xiaoping Wang,Yuantao Liu,Liqing Dong,Xiaobin Yu
ω-transaminase can mediate the asymmetric synthesis of chiral amines from aldehydes and ketones , which has important value in the synthesis of pharmaceutical intermediates. A novel ω-transaminase derived from Paracoccus pantotrophus ( Pp TA) was obtained and cloned in E. coli BL21(DE3) for expression. The enzyme has high activity for 2-ketobutyric acid and benzylamine , as well as for aromatic compounds with side chains longer than ethyl aliphatic hydrocarbons . Molecular simulation showed that the S-pocket in the active center is larger than those of other ω-transaminases. Thereafter, a whole-cell catalytic system was designed to prepare l -2-aminobutyric acid by cascading Pp TA and other enzymes. By using several strategies (regulation of RBS intensity, by-product decomposition and cofactor self-sufficiency), whole-cell cascade biocatalysis showed a high ee value (> 99%) and high yield (71%) in one pot reaction . This study therefore proposes an efficient biocatalyst for the synthesis of unnatural amino acids with the participation of ω-transaminase.
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JOURNAL OF MOLECULAR LIQUIDS
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2021
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IF 6.165
Mingcheng Li,Chunying Zhu,Taotao Fu,Youguang Ma
In this study, the densities and viscosities of the binary solutions 1-dimethylamino-2-propanol (1DMA2P) + H 2 O, benzylamine (BZA) + H 2 O, 1DMA2P + BZA and ternary solution 1DMA2P + BZA + H 2 O were measured at T = (298.15−333.15) K. Furthermore, the volumetric and the viscometric properties including the excess molar volume, partial molar volume, apparent molar volume, limiting apparent molar volume, viscosity deviation, excess Gibbs energy of activation for viscous fluid and Grunberg-Nissan interaction parameters were obtained in terms of experimental data, respectively. The excess molar volumes of binary and ternary solutions were fitted by the Redlich-Kister equation and Cibulka equation, besides, the viscosity and viscosity deviation of binary solution were correlated by using the Grunberg-Nissan equation and Redlich-Kister equation. Moreover, the intermolecular interactions were analyzed based on the volumetric and viscometric properties of solutions.
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FITOTERAPIA
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2021
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IF 2.882
Rui Zha,Enhui Ge,Lirong Guo,Qing Gao,Qiqi Lin,Wan Zhou,Xiaobao Jin,Weiquan Xie,Hui Yin,Tao Liu
Macamides are a class of bioactive amide alkaloids found only in maca ( Lepidium meyenii ). Recent studies have shown that macamide-rich extracts possess various biological activities , such as antioxidative, immune-enhancing, and reproductive health-improving activities. In the present study, N-benzyl docosahexaenamide (NB-DHA), a newly identified macamide with the highest degree of unsaturation among all identified macamides, was identified from the maca extract. Microalgae oil, a docosahexaenoic acid-rich substance, was used as the starting material for the synthesis of NB-DHA. The effects of NB-DHA in colitis-induced mice were evaluated. NB-DHA significantly alleviated weight loss, shortening of colon length, and occult blood occurrence in mice with dextran sulfate sodium-induced colitis . Histological analysis revealed that following the administration of NB-DHA in mice with colitis, the infiltration of inflammatory cells and levels of proinflammatory factors, such as tumor necrosis factor-α, interleukin (IL)-1β, IL-6, and myeloperoxidase , decreased, whereas the level of the anti-inflammatory factor IL-10 increased. Furthermore, the decreased expression of intestinal tight junction proteins caused by colitis was upregulated by the administration of NB-DHA. These results indicate that NB-DHA could be developed as a therapeutic agent for ulcerative colitis .
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PubMed
高影响因子
MOLECULES
·
2021
·Vol. 26
·期 11
·3108
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IF 4.412
Mengya Jiao,Qun Dong,Yiting Zhang,Min Lin,Wan Zhou,Tao Liu,Baohong Yuan,Hui Yin
Maca (Lepidium meyenii) has emerged as a popular functional plant food because of its medicinal properties and nutritional value. Macamides, as the exclusively active ingredients found in maca, are a unique series of non-polar, long-chain fatty acidN-benzylamides with multiple bioactivities such as antifatigue characteristics and improving reproductive health. In this study, a new kind of macamide,N-benzyl eicosapentaenamide (NB-EPA), was identified from maca. We further explore its potential neuroprotective role in hypoxic–ischemic brain injury. Our findings indicated that treatment with biosynthesized NB-EPA significantly alleviates the size of cerebral infarction and improves neurobehavioral disorders after hypoxic–ischemic brain damage in neonatal mice. NB-EPA inhibited the apoptosis of neuronal cells after ischemic challenge. NB-EPA improved neuronal cell survival and proliferation through the activation of phosphorylated AKT signaling. Of note, the protective property of NB-EPA against ischemic neuronal damage was dependent on suppression of the p53–PUMA pathway. Taken together, these findings suggest that NB-EPA may represent a new neuroprotectant for newborns with hypoxic–ischemic encephalopathy.Keywords:maca;N-benzyl eicosapentaenamide;neonatal hypoxic–ischemic encephalopathy;neuroprotection;PUMA
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Food Analytical Methods
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2021
·Vol. 14
·期 6
·1121-1132
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IF 3.366
Sun Chao,Gao Xiaoqi,Wang Lei,Zhou Nan
Reactive nitrogen species (RNS) are vital signaling molecules involved in most physiological and pathological processes. Within RNS, nitric oxide (NO) and its metabolite nitrite (NO 2 − ) have been widely applied in medicinal, food, and environmental fields. However, at present, the methods of detecting RNS by fluorescence quenching through chemical reactions have disadvantages, such as long reaction time and weak anti-interference ability. In response to these existing problems, we have developed a novel fluorescent probe, namely, carbon quantum dots (CDs) that are passivated by benzylamine. The obtained CDs (named B-CDs) possess excellent down- and upconversion properties. In particular, upconversion is used to sensitively and selectively measure NO and NO 2 − under different pH conditions in aqueous media via two different mechanisms (static and dynamic quenching). At pH 7.4, the nanomolar concentration of NO, produced from sodium nitroprusside (SNP) in a concentration-dependent manner, can be rapidly detected with a correlation coefficient ( R 2 ) greater than 0.99. Similarly, the quantitative detection of NO 2 − at pH 1.6 also shows a good linear relationship with a linear range of 0–14 μM, and a limit of detection (LOD) that is as low as 43 nM and 0.65 μM at excitation wavelengths of 800 nm and 375 nm, respectively. Notably, this probe stands out due to its extremely short response time and outstanding selectivity and anti-interference ability against a variety of common interfering substances, while realizing the fast and highly selective and sensitive detection of NO and NO 2 − . Finally, this probe has been successfully applied to the sensing of NO in fetal bovine serum (FBS) samples and NO 2 − in milk and tap water samples. Graphical abstract
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Biomaterials Science
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2020
·Vol. 8
·期 24
·6969-6977
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IF 6.183
Bo Zhang,Min Li,Min Lin,Xuan Yang,Jing Sun
Bioinspired polypeptoids show great potential in many applications. Here, we report a convenient approach to synthesize a novel type of polypeptoid containing both sulfonium and oligo(ethylene glycol) (OEG) moieties by ring-opening polymerization (ROP) and a post-modification strategy. Three types of epoxides with (OEG)n (n = 1–3) groups are involved to offer various functionalities. The obtained polypeptoid sulfonium salts show positive ζ potential, irrespective of the solution pH and the degree of polymerization (DP). We demonstrate that the polypeptoids exhibit excellent antibacterial activity against Staphylococcus aureus (S. aureus) with MIC (minimal inhibitory concentration) in the range of 3.9–7.8 μg mL−1. In addition, the polypeptoids have a low hemolysis property and good in vitro biocompatibility. Remarkably, the as-prepared polypeptoids show rapid and potent antibacterial activity within 5 min. These features suggest that the obtained polypeptoids offer great potential for antimicrobial agents.
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RAPID COMMUNICATIONS IN MASS SPECTROMETRY
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2021
·Vol. 35
·期 9
·e9062
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IF 2.419
Shaolan Wang,Jinsheng Lin,Dan Li,Tianpei Huang,Wenquan Zhu,Wenbin Chen,Min Li,Weiyang Shen
Rationale The focus of this work was to study glycosylamine and Amadori rearrangement products (ARPs), the two major degradants in the Maillard reactions of pharmaceutical interest, and utilize their MS 2 fingerprints by liquid chromatography/high-resolution tandem mass spectrometry (LC/HRMS 2 ) to quickly distinguish the two isomeric degradants. These two types of degradants are frequently encountered in the compatibility and stability studies of drug products containing primary or secondary amine active pharmaceutical ingredients (APIs), which are formulated with excipients consisting of reducing sugar functionalities. Methods Vortioxetine was employed as the primary model compound to react with lactose to obtain the glycosylamine and ARP degradants of the Maillard reaction, and their MS 2 spectra (MS 2 fingerprints) were obtained by LC/MS 2 . Subsequently, the two degradants were isolated via preparative HPLC and their structures were confirmed by one- and two-dimensional (1D and 2D) nuclear magnetic resonance (NMR) determination. Results The MS 2 fingerprints of the two degradants display significantly different profiles, despite the fact that many common fragments are observed. Specifically, protonated glycosylamine shows a prominent characteristic fragment of [M vort + C 2 H 3 O] + at m/z 341 (M vort is the vortioxetine core), while protonated ARP shows a prominent characteristic fragment of [M vort + CH] + at m/z 311. Further study of the Maillard reactions between several other structurally diverse primary/secondary amines and lactose produced similar patterns. Conclusions The study suggests that the characteristic MS 2 fragment peaks and their ratios may be used to differentiate the glycosylamine and ARP degradants, the two isomeric degradants of the Maillard reaction, which are commonly encountered in finished dosage forms of pharmaceutical products containing primary and secondary amine APIs.
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SENSORS AND ACTUATORS B-CHEMICAL
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2021
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IF 7.46
Zongyan Quan,Hui He,Hang Zhou,Yuting Liang,Lei Wang,Songya Tian,Hongxiang Zhu,Shuangfei Wang
The low sensitivity of fluorescent sensors limits the on-site and visual detection of seafood freshness. To address these issues, a novel intelligent nanofiber ratiometric fluorescent sensor, known as a BAsCNF, was designed using cellulose nanofibers (CNFs) produced by TEMPO oxidation (TO-CNFs) as the skeleton, and fluorescein isothiocyanate and proporphyrin IX modified nanofibers as the indicator and internal reference, respectively. TO-CNFs with nano-scale characteristics improved the air permeability of BAsCNF films, which endowed the sensor with excellent response performance to biogenic amines (BAs). Thus, the BAsCNF produced obvious colour changes from red to yellow-green in response to an increased concentration of BAs, where the limit of detection for BAs was as low as 1 ppm. Meanwhile, the discoloration trend of the BAsCNF in the freshness detection of shrimp and pork was consistent with the variation of the key indicators during storage, such as the content of total volatile basic nitrogen and the total number of colonies. The results suggest that the BAsCNF sensor possessed high detection accuracy and broad application prospects in the field of food safety.
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BIOMACROMOLECULES
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2020
·
IF 6.092
Zhiwei Wang,Min Lin,Colin Bonduelle,Rongye Li,Zhekun Shi,Chenhui Zhu,Sébastien Lecommandoux,Zhibo Li,Jing Sun
Delicate control over architectures via crystallization-driven self-assembly (CDSA) in aqueous solution, particularly combined with external stimuli, is rare and challenging. Here, we report a stepwise CDSA process thermally initiated from amphiphilic poly(N-allylglycine)-b-poly(N-octylglycine) (PNAG-b-PNOG) conjugated with thiol-terminated triethylene glycol monomethyl ethers ((PNAG-g-EG3)-b-PNOG) in aqueous solution. The diblock copolymers show a reversible thermoresponsive behavior with nearly identical cloud points in both heating and cooling runs. In contrast, the morphology transition of the assemblies is irreversible upon a heating–cooling cycle because of the presence of a confined domain arising from crystalline PNOG, which allows for the achievement of different nanostructured assemblies by the same polymer. We demonstrated that the thermoresponsive property of PNAG-g-EG3 initiates assembly kinetically that is subsequently promoted by crystallization of PNOG thermodynamically. The irreversible morphology transition behavior provides a convenient platform for comparing the cellular uptake efficiency of nanostructured assemblies with various morphologies that are otherwise similar.
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CHEMISTRY OF MATERIALS
·
2019
·
IF 10.159
Qin Wang,Jin Li,Xianjun Tu,Hongbo Liu,Miao Shu,Rui Si,Calum T. J. Ferguson,Kai. A. I. Zhang,Run Li
Generation of efficient light-induced charge separation inside the photocatalyst is an essential factor for a high catalytic efficiency. The usual immobilization of metal or metal oxide particles on semiconductor photocatalysts offers an uncontrolled assembly of active sites during the reaction. The introduction of single metal atoms on photocatalysts can lead to extremely high atomic utilization and precise active sites. However, this approach is limited because of the lack of suitable photosensitizers for single atom immobilization. Here, we have designed photocatalytic carbon quantum dots with anchoring sites for single cobalt atoms in a defined Co–N4 structure via facile pyrolysis of vitamin B12. Carbon dots functioned as both light-harvesting antenna and support for the cobalt atom with high atom loadings up to 3.27 wt %. This new photocatalytic material demonstrated enhanced visible light absorption, efficient charge separation, and reduced electrochemical impedance, while single Co atoms acted as the active site with strong oxidative ability. As a result, the photocatalysts showed excellent visible light-promoted photocatalytic efficiency with oxygen evolution rates up to 168 μmol h–1 g–1 via water oxidation, imine formation with high conversion (∼90%) and selectivity (>99%), and complete photodegradation of organic dyes.
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APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
·
IF 14.229
Yu Ding,Bo-Qiang Miao,Shu-Ni Li,Yu-Cheng Jiang,Yan-Yan Liu,Hong-Chang Yao,Yu Chen
In this work, ultra-thin Ni 2 P nanomeshes (1.9 nm thickness) on nickel foam (NF) substrate (denoted as Ni 2 P-UNMs/NF) are successfully achieved through phosphidation treatment using ultra-thin Ni(OH) 2 nanomeshes on NF substrate (denoted as Ni(OH) 2 -UNMs/NF) as reaction precursor. Because of the sufficient active sites in edge of the holes, high specific surface area, porous framework and high conductivity of NF substrate, Ni 2 P-UNMs/NF nanocomposites show the outstanding activity for both hydrogen evolution reaction (HER) and benzylamine oxidation reaction (BOR) in alkaline electrolyte. Importantly, Ni 2 P-UNMs/NF nanocomposites can directly act as a bifunctional electrocatalyst for the electrochemical water-splitting in two electrode system in the presence of benzylamine, which only requires an electrolysis voltage of 1.41 V to achieve the 10 mA cm -2 current density in alkaline electrolyte, accompanying with H 2 production at cathode and value-added benzonitrile production at anode. Obviously, the BOR boosted electrochemical water-splitting provides an energy-saving and cost-competitive H 2 production method.
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