ANALYTICAL LETTERS
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2023
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IF 2
Jia Song,Jiaying Yu,Kai Sun,Zhixin Chen,Xiaoxiao Xing,Yumeng Yang,Chunyu Sun,Zhifei Wang
Given the important role of carboxylesterase 2 (CES2) in the metabolism of various esters, it is of significance to develop a tool to determine endogenous CES2 activity in a rapid and highly selective manner. In this work, an "off-on" rhodamine-based fluorescent probe is reported as an effective tool for CES2 activity. Based on the substrate recognition preference of CES2 (large alcohol and small acyl groups), the probe with dimethyl carbamate as the recognition group performs well in terms of selectivity and sensitivity to CES2. The fluorescence switching control of the probe for CES2 was achieved by using the spirolactone structure of rhodamine. The probe shows the fast generation of a fluorescence signal at 634 nm upon hydrolysis of CES2 with excitation at 578 nm. The results showed a linear relationship between the fluorescence intensity at 634 nm and the CES2 activity from 0 to 4 μg/mL. The probe reacts rapidly with CES2, and the reaction is stable within 40 minutes. The probe is highly selective for CES2, with a detection limit as low as 0.303 μg/mL. In addition, the probe has currently been successfully utilized to evaluate CES2 activity in living cells. Hence, this probe is anticipated to be significant in identifying endogenous CES2 activity in intricate biological settings.
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JOURNAL OF CHROMATOGRAPHY A
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2022
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IF 4.601
Zhixu Chen,Jincai Wang,Jiaming Yuan,Zhen Wang,Zhengchao Tu,Jacques Crommen,Wenhui Luo,Jialiang Guo,Tingting Zhang,Zhengjin Jiang
In this study, an advanced at-line nanofractionation based screening platform was developed to screen potential neuraminidase inhibitors (NAIs) from Lonicera japonica Thunb by involving two parallel bioassays, for determining both oseltamivir-sensitive neuraminidase (NAS) and oseltamivir-resistant neuraminidase (NAR) inhibitory activities. 20 potential NAIs with both NAS and NAR inhibitory effects were screened from Lonicera japonica Thunb and identified by mass spectrometer, including 11 phenolic acids, 8 flavonoids and one iridoid glycoside. The proposed at-line nanofractionation based screening platform for NAIs was also used to rapidly screen nine batches of water extracts of Lonicera japonica Thunb or its similar species. Clear differences in the number and content of active components were easily observed, demonstrating that the proposed method possesses great potential for the quality control of herb medicines.
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高影响因子
International Journal of Electrochemical Science
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2023
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IF 1.5
Haobin Shi,Yuhong Zheng,Mengyao Wu,Li Fu
In this study, commercial graphene ink has been used as a cost-effective modifier for glassy carbon electrode (GCE) surface modification. The excellent conductivity and defects triggered electrocatalytic property of the graphene ink showed a superior performance in electrochemical sensing. Galantamine, an alkaloid isolated from Lycoris, has been selected as an analyte for evaluating the graphene ink-modified GCE. A clear signal enhancement with reduction of overpotential was observed using a GCE after a simple graphene ink surface modification process. A linear detection range from 20 μM to 180 μM of galantamine was recorded on the proposed electrode with a low limit of detection of 4.1 μM.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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IF 4.784
Wei Li,Chong Qiao,Jing Pang,Guolin Zhang,Yinggang Luo
Amaryllidaceae alkaloids are unique benzylphenethylamine derivatives that comprise of more than 600 members with a huge chemical diversity. Most of them showed interesting bioactivities, for instance, galanthamine (GAL) is clinically used for Alzheimer's disease treatment. All Amaryllidaceae alkaloids had been thought to be derived from 4′- O -methylnorbelladine originated from norbelladine catalyzed by norbelladine 4′- O -methyltransferase (N4OMT). Herein we mined the transcriptome datasets of Lycoris radiata , a GAL-producing plant. LrOMT was cloned, overexpressed in Escherichia coli , and purified to homogeneity. Bioinformatics analysis and enzymatic activity assays revealed that LrOMT is an S-adenosylmethionine-dependent Class I OMT. LrOMT exhibited both para - and meta - O -methylation activities toward norbelladine to give 4′- and 3′- O -methylnorbelladine. Twenty-four analogues, including the proposed biosynthetic intermediates, were introduced to investigate the substrate scope of LrOMT and it showed that the aromatic substrates should have two vicinal hydroxyl groups. The LrOMT-catalyzed O -methylation preference is dependent on the properties of the binding group of the substrates. The transcription levels of LrOMT were positively associated with the accumulation of the Amaryllidaceae alkaloids and the biosynthetic intermediates in L. radiata . The present work revealed that LrOMT catalyzes multiple O -methylation reactions and its characterization will be helpful to uncover novel biosynthetic genes for Amaryllidaceae alkaloids biosynthesis.
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JOURNAL OF CHROMATOGRAPHY A
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2018
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IF 3.716
Yu-Mei Zhao,Lv-Huan Wang,Si-Fan Luo,Qi-Qin Wang,Ruin Moaddel,Ting-Ting Zhang,Zheng-Jin Jiang
Neuraminidase (NA) is a glycoside hydrolase that has been proposed as a potential therapeutic target for influenza. Thus, the identification of compounds that modulate NA activity could be of great therapeutic importance. The aim of this study is to develop a drug discovery tool for the identification of novel modulators of NA from both compound libraries and natural plant extracts. NA was immobilized onto the surface of magnetic beads and the inherent catalytic activity of NA-functionalized magnetic beads was characterized. Based on the enzymatic activity (hydrolysis ratio), the inhibitory activities of 12 compounds from plant secondary metabolites were screened, and the desired anti-NA activities of flavonoids were certified. Ligand fishing with the immobilized enzyme was optimized using an artificial test mixture consisting of oseltamivir, lycorine and matrine prior to carrying out the proof-of-concept experiment with the crude extract of Flos Lonicerae . The combination of ligand fishing and HPLC-MS/MS identified luteolin-7- O -β-D-glucoside, luteolin, 3,5-di- O -caffeoylquinic acid and 3,4-di- O -caffeoylquinic acid as neuraminidase inhibitory ligands in Flos Lonicerae . This is the first report on the use of neuraminidase functionalized magnetic beads for the identification of active ligands from a botanical matrix, and it sets the basis for the de novo identification of NA modulators from complex biological mixtures.
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JOURNAL OF CHROMATOGRAPHY A
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2018
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IF 3.716
Lvhuan Wang,Yumei Zhao,Yanyan Zhang,Tingting Zhang,Jeroen Kool,Govert W. Somsen,Qiqin Wang,Zhengjin Jiang
In order to develop a direct and reliable method for discovering lead compounds from traditional Chinese medicines (TCMs), a comparative online ligand fishing platform was developed using immobilized capillary enzyme reactors (ICERs) in combination with liquid chromatography-mass spectrometry (LC–MS). Methacrylate-based monolithic capillaries (400 μm I.D. × 10 cm) containing epoxy reactive groups were used as support to immobilize the target enzyme acetylcholinesterase (AChE). The activity and kinetic parameters of the AChE-ICER were investigated using micro-LC-UV. Subsequently, ligand fishing and identification from mixtures was carried out using the complete AChE-ICER-LC–MS platform. For efficient distinction of true actives from false positives, highly automated comparative analyses were run alternatingly using AChE-ICERs and negative control-ICERs, both online installed in the system. After washing unbound compounds to the waste, bound ligands were eluted from the AChE-ICER to a trapping loop using a denaturing solution. The trapped ligands were further separated and identified using LC–MS. Non-specific binding to the monolith support or non-functional sites of the immobilized enzyme was investigated by exposing analytes to the negative control-ICER. The specificity of the proposed approach was verified by analyzing a known AChE inhibitor in the presence of an inactive compound. The platform was applied to screen for AChE inhibitors in extracts of Corydalis yanhusuo . Eight compounds (columbamine, jatrorrhizine , coptisine , palmatine , berberine , dehydrocorydaline, tetrahydropalmatine and corydaline) with AChE binding affinity were detected and identified, and their AChE inhibitory activities were further verified by an in vitro enzymatic inhibition assay. Experimental results show that the proposed comparative online ligand fishing platform is suitable for rapid screening and mass-selective detection of AChE inhibitors in complex mixtures.
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INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
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2013
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IF 2.142
Tingting Cai,Li Zhang,Rong Wang,Chen Liang,Yurong Zhang,Yinlong Guo
Ammonium perfluorooctanoate (APFO) is a commercially important compound, but its harm to people's health has raised widespread concern. In the past, the investigations into APFO and its degradation product (perfluorooctanoic acid, PFOA) were all about their effect on indicator compounds in animals and enzyme activities. Here, we provided a new suggestion to investigate the influence of APFO and PFOA. Acetylcholinesterase (AChE) was chosen as research subject to reflect the effect of external perfluorochemicals. We applied matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICRMS) to detect the activity of AChE rapidly and accurately. On this basis, not only AChE activity but also AChE inhibition was studied carefully. The presence of APFO and PFOA showed obvious increase of AChE activity. Moreover, addition of both APFO and PFOA had enhanced AChE inhibition from organophosphorous (OP) pesticide (irreversible inhibitor). Otherwise, the participation of APFO and PFOA had not increased AChE inhibitions from reversible inhibitor galantamine. These results might provide new insights into the effect of APFO and encourage the deep understanding about effect of APFO on human being.
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NEUROSCIENCE
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2018
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IF 3.382
Lingqi Gao,Junde Han,Jie Bai,Jing Dong,Sen Zhang,Mazhong Zhang,Jijian Zheng
Early synchronized spontaneous network activity is a hallmark of the brain growth spurt period, during which general anesthetics cause widespread neuronal apoptosis and subsequent cognitive dysfunction. However, the relationship of such activity to anesthetic-induced neuronal apoptosis remains to be determined. In this study, we utilized patch-clamp electrophysiological recording, immunohistochemistry, and TUNEL assays to investigate the potential roles of spontaneous network activity in ketamine-induced neuronal apoptosis during early development. All experiments were performed using acutely dissected whole-mount Sprague–Dawley rat retinas (0–14 postnatal days [P0–P14]). Ketamine reversibly blocked spontaneous network activity in the rat retina from P0 to P9 and irreversibly blocked such activity from P10 to P12. The peak of physiological and ketamine-induced neuronal apoptosis mainly occurred from P7 to P9. Blockade of nicotinic acetylcholine receptors (nAChRs) also induced reversible inhibition of spontaneous network activity from P0 to P7 and extensive neuronal apoptosis in the P7 rat retina, while activation of nAChRs or increases in endogenous ACh levels attenuated ketamine-induced apoptotic responses. Furthermore, blockade of α7-nAChR and ß2-nAChR subtypes induced neuronal apoptosis in the developing retina, while activation of the α7-nAChR subtype attenuated ketamine-induced apoptotic responses. These results demonstrate that ketamine may inhibit early synchronized spontaneous network activity by blocking nAChRs, and that such inhibition may contribute to ketamine-induced neuronal apoptosis in the developing rat retina.
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MICROCHEMICAL JOURNAL
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2024
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IF 4.9
Chongyang Mu,Mashooq Khan,Jinpeng Liu,Xinfeng Dong,Zhengtong Wang,Ping Song,Qiongzheng Hu,Li Yu
The development of new types of sensing platforms with excellent performance is always appealing. In this report, we demonstrate a low-cost and user-friendly sensing platform based on drying of the aqueous droplet on the surface. The principle relies on the transduction of the surfactant concentration into the area of the dried droplet on the surface. The screening of a lipase inhibitor is demonstrated as an example. When triacylglycerols (GT) and lipase are mixed, the aqueous droplet produces a large dried area on the surface. This phenomenon is attributed to the production of sodium oleate due to the enzymatic digestion of GT by lipase. It results in reduction of the surface tension and causes wetting and spreading of the droplet, leaving a large dried area on the surface. However, in the presence of orlistat, a lipase inhibitor, a small dried area is obtained due to the inhibition of lipase activity by orlistat. Using this method, the lipase inhibitor can be readily and effectively screened. Compared to previous studies, this method is simple, rapid, low-cost and avoids the use of labelled molecules and complex instrumentation, with an IC 50 value of 0.59 ± 0.09 μM for orlistat. In addition, it also works well with a portable microscope and a smartphone interface for data analysis. Overall, this study provides a new method for rapid and cost-effective screening of lipase inhibitors.
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