TALANTA
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2022
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IF 6.556
Meini Li,Yunfei Xie,Donghui Song,Hui Huang,Yongxin Li
In this work, 2-methylimidazole (MI) was doped into the Bpy-Cu nanozyme as a second ligand to form a novel laccase-mimicking enzyme (MI-Bpy-Cu). By comparison, MI-Bpy-Cu nanozyme was identified to have excellent laccase-mimicking activity, high stability and catalytic kinetic properties. It may be that the incorporation of 2-methylimidazole helped the nanozymes to build a structure closer to natural laccase and accelerate the electron transfer rate, thereby achieving the purpose of enhancing the activity. Furthermore, we observed that MI-Bpy-Cu nanozymes could oxidize the colorless (+)-Catechin to generate a yellow radical product, and a novel colorimetric sensing strategy for (+)-Catechin was successfully developed. The method had excellent selectivity and anti-interference properties, and also had good application in the analysis of (+)-Catechin in dairy products.
研究领域:
纳米技术
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分析化学
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食品科学
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DOI
PubMed
高影响因子
Journal of Functional Foods
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2017
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IF 3.144
Shan Hong,Shanshan Wu,He Cai,Yimin Wang,Songbai Liu
Proton NMR signals of the phenolic hydroxyl groups of the substituted catechins were successfully collected. The identities of these signals were elucidated and confirmed by a combination of computational and experimental investigations including GIAO-B3LYP NMR chemical shift calculation, kinetic analysis of acylation, and NOESY correlation. Furthermore, the reliability of chemical shifts of hydrogens of phenolic hydroxyl groups was confirmed by evaluation of the influence of acidic, basic and water residues. Finally, the chemical shift profiles of phenolic hydroxyl groups were developed for instant structural recognition. This study demonstrated the feasibility of application of chemical shifts of hydrogens of phenolic hydroxyl groups as fingerprint for structural determination and the concept could be extended to other polyphenols.
研究领域:
植物化学
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分析化学
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计算化学
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DOI
高影响因子
eFood
·
2023
·Vol. 4
·期 2
·e64
·
IF 0
Yuhong Li,Xiaoling Chen,Yueli Lin,Yaqi Yang,Li Zhang,Pengcheng Zhao,Chenxi Wang,Junjie Fei,Yixi Xie
Catechin (Cat) is one of the primary functional components of tea, and its accurate detection is significant for understanding the health benefits of tea. In this study, cyclodextrin nanosponges (CDNS) were prepared and employed to combine with graphene quantum dots (GQDs) and carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) to form a CDNS/GQDs/MWCNTs-COOH composite. Scanning electron microscope and X-ray diffraction were used to characterize the composite which was used to build a new electrochemical Cat sensor. The abundance of cavities, intermolecular gaps, and surface active groups of CD molecules endowed CDNS with remarkable Cat enrichment capacity. Due to the outstanding biocompatibility of GQDs, the good electrocatalytic activity of MWCNTs-COOH, and the enrichment capacity of CDNS, the composite modified glass carbon electrode (GCE) exhibited excellent electrochemical sensing performance. The CDNS/GQDs/MWCNTs-COOH/GCE showed a sensitive peak current response to catechins in the linear range between 2 × 10 −8 and 1.2 × 10 −6 M, with a minimum limit of detection (S/N = 3) of 4.45 nM. The sensor has also been successfully applied for catechin detection in tea beverages.
研究领域:
分析化学
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纳米技术
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食品科学
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DOI
Frontiers in Plant Science
·
2016
·
IF 4.495
Xu Huanhuan,Wang Ya,Chen Yana,Zhang Pan,Zhao Yi,Huang Yewei,Wang Xuanjun,Sheng Jun
Galloylated catechins, as the main secondary metabolites in the tea plant, including (-)-epigallocatechin-3-gallate and (-)-epicatechin-3-gallate, comprise approximately three-quarters of all the tea plant catechins and have stronger effects than non-galloylated catechins, both on the product quality in tea processing and the pharmacological efficacy to human beings. The subcellular localization of galloylated catechins has been the primary focus of studies that assess biosynthesis and physiological functions. Classical histochemical localization staining reagents can not specifically detect galloylated catechins; thus, their subcellular localization remains controversial. In the present study, we generated a monoclonal antibody (mAb) against galloylated catechins, which can be used for the subcellular localization of galloylated catechins in the tea plant by immunohistochemistry. Direct ELISA and ForteBio Octet Red 96 System assay indicated the mAb could recognize the galloylated catechins with high specificities and affinities. In addition, tea bud was ascertained as the optimal tissue for freezing microtomic sections for immunohistochemistry. What’s more, the high quality mAbs which exhibited excellent binding capability to galloylated catechins were utilized for the visualization of them via immunohistochemistry. Our findings demonstrated that vacuoles were the primary sites of localization of galloylated catechins at the subcellular level.
研究领域:
植物科学
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生物化学
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分子生物学
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DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2021
·
IF 4.952
Pengfei Zhou,Daobang Tang,Jinhao Zou,Xuping Wang
The low stability and loss of antimicrobial activity of catechins limited their application in food preservation. In this study, four kinds of catechins including (−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-epicatechin-3-gallate (ECG), and (−)-epigallocatechin-3-gallate (EGCG) were selected as model compounds. Natural deep eutectic solvents (NADES) are a new generation of green solvents that have attracted much attention due to their unique characteristics. The effects of NADES on the stability and antimicrobial activity of catechins were investigated in the present study. Eight typical NADES, especially choline chloride/glycerol (ChG), were found to significantly enhance the thermal and storage stability of catechins. This finding accounted for by hydrogen bonding network formation between ChG and catechins, confirmed by FT-IR and 2D NMR analysis. Additionally, ChG decreased the minimum inhibitory concentration of catechins on Gram-positive and Gram-negative bacteria, which may be associated with its stabilizing property. The stability of catechins combined with NADES revealed their potential of applications in the food industry.
研究领域:
食品科学
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生物化学
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DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2022
·
IF 7.425
Jifan Zhang,Shuangshuang Li,Xuebo Liu,Lijun Sun
Inhibiting carbohydrate-hydrolyzing enzymes has been considered as an effective approach for controlling starch digestion and postprandial blood glucose level. α-Amylase and amyloglucosidase (AMG) are commonly applied in analysis of starch digestion behaviour. Catechins have been shown with the inhibiting effects on α-amylase. However, the inhibitory activity of catechins against AMG needs to be further studied. Therefore, AMG inhibition of 8 catechins and the mechanisms were studied in this work through substrate depletion, inhibition kinetics, molecular docking, fluorescence quenching, differential scanning calorimetry, and isothermal titration calorimetry. The inhibitory activity of catechins with galloyl moiety (CGMs) was found to be lower than the corresponding catechins without the moiety (Cs). All catechins were anti-competitive inhibitors, indicating that they tended to bind with AMG-starch complex in the digestion system, rather than with AMG directly. Interestingly, CGMs had higher quenching effects on AMG fluorescence than Cs, due to the additional π-stacking between aromatic rings of GM and AMG fluorophores. Also, CGMs had a higher binding affinity to AMG, due to the tendency of GM to AMG active site, although the affinity was much weaker than that of starch to AMG. Besides, catechins did not affect AMG thermostability. Therefore, there was an inconsistency between catechins-AMG binding interactions and the enzyme inhibition because the predominant sites for catechins binding were the non-active sites on AMG-starch complex, rather than the enzyme active ones. Conclusively, inhibition mode should also be considered when evaluating the inhibitory activity of a polyphenol based on the polyphenol-enzyme binding affinity.
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PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2024
·
IF 7
Qiu-Yue Ma,Qian-Da Xu,Nan Chen,Wei-Cai Zeng
Effects of catechins with different structure characteristics on the structure and properties of gluten-catechin covalent complex were investigated, and the structure–activity relationship was further explored. Catechins including epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and epigallocatechin-3-gallate (EGCG) could successfully covalently bind with gluten through C-N and/or C-S bonds. The physicochemical properties of covalent complex, including particle size, thermal stability, content of free amino groups, free sulfhydryl groups and disulfide bonds, were significantly affected by different catechins, and the action order was: EGCG > ECG > EGC > EC. Multispectral analysis indicated that catechins significantly changed the tertiary and secondary structures of covalent complex, while galloylated catechins (ECG and EGCG) showed stronger capability than non-galloylated catechins (EC and EGC). Furthermore, the in vitro protein digestibility of covalent complexes reduced with all catechins, and its polyphenols release rate and antioxidant activity were improved. Combining multispectral analysis and molecular dynamics simulation, the hydroxyl group at 5th position in B ring and the galloyl group at 3rd position in C ring played an important role to affect the covalent binding of catechins and gluten, while the amount of hydroxyl groups and the molecule size of catechins both significantly affected its capability to covalently bind with gluten.
研究领域:
食品科学
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生物化学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2024
·
IF 8.5
Huihui Li,Zhuangwei Zhang,Jin Chen,Mengchu Sun,Hongjin Tang
This study aimed to elucidate how Cu 2+ influences the interaction between catechins and zein using multi-spectral and molecular modeling techniques. As a result, UV–vis spectra revealed characteristic changes, indicating chelation between catechins and Cu 2+ at a 1:1 M ratio. Fluorescence spectra further confirmed interaction through a static quenching mechanism between catechins/catechin-Cu 2+ complexes and zein. Catechins induced changes in the microenvironment and hydrophobicity surrounding the binding site of zein, whereas Cu 2+ had minimal impact on these aspects. CD spectra underscored catechins' role in altering zein's secondary structure conformation, alongside Cu 2+ . Various types of interactions (hydrophobic, hydrogen bonding, electrostatic, and van der Waals) contributed to the binding of catechins/catechin-Cu 2+ complexes with zein. Molecular modeling elucidated key residues and binding conformations, highlighting the significance of hydrophobic interactions and hydrogen bonding in their association. These findings not only deepen our understanding of catechin-Cu 2+ -zein interactions but also underscore their potential applications in the food industry.
研究领域:
食品科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2026
·
IF 13.8
Xueqing He,Jinhui Hu,Lei Chen,Yihan Huang,Chenxi Fan,Songyi Lin,Na Sun
Interactions between proteins and polyphenolic compounds are essential for modulating both structural integrity and functional behavior within acidic food matrices. However, existing studies have focused on globular proteins under neutral conditions, leaving protein-polyphenol interactions in acidic environments insufficiently understood. In this study, Antarctic krill protein amyloid fibrils (AF) were employed as a model system to systematically investigate their interactions under acidic conditions with structurally distinct catechins, including epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG). The results indicated that catechins formed stable complexes with AF, which caused pronounced alterations in particle size, surface charge, and microstructural morphology. Esterified catechins, particularly EGCG, exhibited enhanced binding strength and induced more substantial modifications compared with non-esterified counterparts. Spectroscopic and thermodynamic analyses revealed that the association between AF and catechins was dominated by non-covalent interactions and proceeded as a spontaneous and exothermic binding process. These interactions induced β-sheet structure rearrangement and accelerated the shift from ordered fibrillar assemblies to more disordered aggregates under acidic conditions. At the cellular level, AF-catechin complexes exhibited good biocompatibility and effectively alleviated H 2 O 2 -induced oxidative stress. Overall, this study elucidates the structure-dependent interaction mechanisms between protein amyloid fibrils and polyphenols, providing a theoretical basis for the design of protein-polyphenol composite systems in acidic functional food applications.
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高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2020
·Vol. 43
·期 15
·3136-3145
·
IF 2.878
Hao Zhang,Min Lu,Hui Jiang,Xu Wang,Feng-Qing Yang
In this study, a capillary electrophoresis-based online immobilized enzyme microreactor was developed for evaluating the inhibitory activity of green tea catechins and tea polyphenol extracts on trypsin. The immobilized trypsin activity and other kinetic parameters were evaluated by measuring the peak area of the hydrolyzate of chromogenic substrate S-2765. The results indicated that the activity of the immobilized trypsin remained approximately 90.0% of the initial immobilized enzyme activity after 30 runs. The value of Michaelis–Menten constant ( K m ) was (0.47 ± 0.08) mM, and the half-maximal inhibitory concentration (IC 50 ) and inhibition constant ( K i ) of benzamidine were measured as 3.34 and 3.00 mM, respectively. Then, the inhibitory activity of four main catechins (epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate) and three tea polyphenol extracts (green tea, white tea, and black tea) on trypsin were investigated. The results showed that four catechins and three tea polyphenol extracts had potential trypsin inhibitory activity. In addition, molecular docking results illustrated that epigallocatechin gallate, epicatechin gallate, epicatechin, and epigallocatechin were all located not only in the catalytic cavity, but also in the substrate-binding pocket of trypsin. These results indicated that the developed method is an effective tool for evaluating inhibitory activity of catechins on trypsin.
研究领域:
分析化学
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生物化学
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药理学
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食品科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2020
·
IF 3.721
Zhou-Tao Fang,Wen-Ting Yang,Cun-Yu Li,Da Li,Jun-Jie Dong,Dong Zhao,Hai-Rong Xu,Jian-Hui Ye,Xin-Qiang Zheng,Yue-Rong Liang,Jian-Liang Lu
Flavonoids are important phenolic compounds in tea plant since they have a large number of physiological functions for plants themselves and human beings. Tea samples (n = 151) harvested from 3 varieties, 9 plantation areas and 107 cultivars were analyzed to describe the attributes of catechins and flavonol glycosides in China. A support vector machine (SVM) classifier was built to recognize the assamica variety with 94.2 % accuracy. Accumulation of (-)-epicatechin gallate (ECG) and flavonol di-glycosides was especially observed in assamica variety, while (-)-epigallocatechin gallate (EGCG) and flavonol tri-glycosides were obviously accumulated in sinensis variety. The ratios of ECG/EGCG and flavonol tri-glycosides/flavonol di-glycosides could be used as indicators for distinguishing the different varieties and cultivars. Accumulation pattern of catechins and flavonol glycosides were mainly dependent on the genetic background of the cultivars rather than plantation locations. The increased hydroxyl groups at the C-ring of catechins and the extended sugar chain at the B-ring of flavonol glycosides could be considered as important rules of metabolite change during tea plant evolution. The mechanism of accumulation of flavonoids in various varieties and cultivars was also discussed.
研究领域:
植物学
·
代谢组学
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食品科学
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高影响因子
Food Biophysics
·
2022
·Vol. 17
·期 4
·586-597
·
IF 3.34
He Wen-Jing,Chen Nan,Yu Zhi-Long,Sun Qun,He Qiang,Zeng Wei-Cai
Effect of catechins with different structure complexity on the properties of glutenins was investigated, and its action mechanism and potential application were further explored. Four catechins, including epicatechin (EC), epigallocaetchin (EGC), epicatechin-3-gallate (ECG) and epigallocatechin-3-gallate (EGCG), could cause glutenins aggregation, further changed the spatial structures and thermal stability of glutenins, and the action sequence of catechins was as: EGCG > ECG > EGC > EC. Meanwhile, all catechins might not interrupt the covalent bonds of glutenins including peptide bonds and disulfide bonds. By molecular docking analysis, hydrogen and hydrophobic bonds were the main molecular interactions between catechins and glutenins, and the binding strength of catechins on glutenins could be ranked as: EGCG > ECG > EGC > EC. Results indicated that esterified catechins (EGCG and ECG) had stronger binding effects on glutenins than non-esterified catechins (EGC and EC). Furthermore, catechins in tea polyphenols could interact with glutenins in wheat flour, and improved the quality of bread including structure, specific volume, texture and color. All present results suggested that the gallic acyl group and hydroxyl group in catechins could promote the interaction of catechins with glutenins, and catechins could significantly affect the spatial structure and physicochemical properties of glutenins. So, catechins showed the potential for improving the properties of glutenins in chemical and food industries. Graphical Abstract
研究领域:
食品科学
·
化学
·
生物分子相互作用
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高影响因子
危险品化学品经营许可证（带存储）