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  • Oxidative damage and apoptosis of lens epithelial cells (LECs) are the primary factors contributing to the development of age-related cataracts (ARC). The potential protective effects of epigallocatechin gallate (EGCG) on LECs remain unclear despite its remarkable antioxidant and anti-apoptotic properties. The aim of this study was to explore the role of serine/threonine-protein kinase (PAK1) in EGCG-mediated attenuation of H2O2-induced apoptosis of LECs in vivo and in vitro.

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  • Epigallocatechin gallate (EGCG) primarily extracted from green tea, exhibits significant antioxidant, hypolipidemic, and anticancer properties. Nevertheless, the limited aqueous solubility and bioavailability of EGCG impede its practical applications. Glycosylation modification of EGCG is an effective method for enhancing its properties. In the present study, a thermally stable variant of sucrose phosphorylase from Streptococcus mutans (SmSP) was identified as having catalytic activity for glycosylation of EGCG. The optimal temperature and pH for SmSP were determined to be 45°C and 6, respectively. The mono-glycosylation product of EGCG was structurally characterized as (-)-epigallocatechin gallate 4'-O-α-D-glucopyranoside. Under optimal reaction conditions (8% methanol, 10g/L EGCG, 300g/L sucrose, 40U/mL crude enzyme, 35°C, and 24h), the conversion rate of EGCG reached 80.79%. Hydrogen bonding interactions between the enzyme and ligands may enhance the stability and catalytic activity of SmSP. Two active site loops significantly influence the selective formation of EGCG glycosides. These insights expand our understanding of the structural basis of sucrose phosphorylases in the synthesis of EGCG glycosides.

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  • Epigallocatechin gallate (EGCG), the predominant catechin in green tea, comprises approximately 50% of its total polyphenol content and has garnered widespread recognition for its significant therapeutic potential. As the principal bioactive component of , EGCG is celebrated for its potent antioxidant, anti-inflammatory, cardioprotective, and antitumor properties. The bioavailability and metabolism of EGCG within the gut microbiota underscore its systemic effects, as it is absorbed in the intestine, metabolized into bioactive compounds, and transported to target organs. This compound has been shown to influence key physiological pathways, particularly those related to lipid metabolism and inflammation, offering protective effects against a variety of diseases. EGCG's ability to modulate cell signaling pathways associated with oxidative stress, apoptosis, and immune regulation highlights its multifaceted role in health promotion. Emerging evidence underscores EGCG's therapeutic potential in preventing and managing a range of chronic conditions, including cancer, cardiovascular diseases, neurodegenerative disorders, and metabolic syndromes. Given the growing prevalence of lifestyle-related diseases and the increasing interest in natural compounds, EGCG presents a promising avenue for novel therapeutic strategies. This review aims to summarize current knowledge on EGCG, emphasizing its critical role as a versatile natural bioactive agent with diverse clinical applications. Further exploration in both experimental and clinical settings is essential to fully unlock its therapeutic potential.

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  • Polyphenol conjugation has emerged as a promising approach to enhance the technological properties and physiological benefits of food proteins. This study investigated the effects of polyphenol conjugation on the technological properties, antioxidant capacity, and in vitro digestibility of chicken breast (CB) proteins. Conjugation with (-)-epigallocatechin 3-gallate (EGCG) and tannic acid (TA) significantly reduced sulfhydryl content. EGCG conjugates exhibited higher turbidity and greater molecular weight aggregates (>245 kDa). Fourier-transform infrared spectroscopy (FTIR) revealed alterations in protein secondary structures, with shifts in amide I and II bands. Polyphenol conjugation significantly enhanced the water-holding capacity of chicken muscle proteins, particularly for CB-TA (3.29 g/g) and CB-EGCG (3.13 g/g) compared to the control (2.25 g/g). The emulsion stability index improved notably in CB-EGCG (96.23 min) and CB-TA (87.24 min) compared to the control (69.05 min). Color analysis revealed darker and more intense hues for CB-EGCG, while CB-TA maintained a lighter appearance, making it potentially preferable for industrial applications requiring neutral-colored powders. Moreover, polyphenol conjugation could enhance antioxidant capacity, particularly in conjugates with EGCG ( < 0.05). In vitro protein digestibility remained comparable across treatments ( > 0.05). Our findings could indicate the potential of chicken muscle protein-polyphenol conjugates as innovative ingredients for high-quality protein supplements.

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  • Wine color and mouthfeel are essential organoleptic characteristics considered by consumers. In this paper, the potential impacts on color and mouthfeel characteristics in wine, without pomace or prolonged pomace contact after different microwave treatment times, were investigated during storage. The results indicated that the trend changes in color and mouthfeel related parameters (including visible spectrum, brightness, red hue, yellow hue, color difference, saturation, hue angle, total polyphenol content, total monomer anthocyanins, total tannins, total flavan-3-ols, epigallocatechin, catechin, epicatechin, epicatechin gallate, and fluorescence spectrum) after microwave-treated and natural aged wines without pomace and prolong pomace contact were very similar. Moreover, changes in these organoleptic parameters of microwave-treated wine were faster than those of untreated wine, which required a long aging time in traditional processing. Also, microwave treatment had a long-term influence on color and mouthfeel characteristics. All these results showed that prolonged pomace contact technology could obviously improve the clarity and yellowness of wine, and microwave technology could reduce wine aging and rapidly change its color and mouthfeel characteristics. In summary, prolonged pomace contact technology is an interesting strategy to replace traditional fining agents. Microwave technology, as an efficient artificial aging technology, might reduce aging time and rapidly change organoleptic characteristics for producing high quality wine.

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  • The astringency of tea, predominantly attributed to epigallocatechin gallate (EGCG), plays a crucial role in shaping its overall quality, and plant-based proteins are gaining popularity as a preferred alternative to milk-based proteins for enhancing the flavor profile of tea. This study investigated the impact of extraction temperature on date palm pollen (DPP) protein quality and tea astringency, comparing temperatures of 30 °C and 80 °C. Results indicated that higher extraction temperatures yield more protein and improve the thermal and surface properties of DPP. The molecular interaction between DPP and EGCG was investigated in an aqueous solution, and spectroscopic analyses (FTIR, UV, and CD) revealed that EGCG interactions at a 1:1 molar ratio induced structural changes in α-helix and β-sheet content in secondary structures in DPP, particularly at 80 °C, which strengthened and enhanced the hydrophobic interactions and hydrogen bonds between DPP molecules as EGCG concentration increased. A sensory evaluation using quantitative descriptive analysis (QDA) confirmed a significant reduction in astringency in DPP-tea polyphenol solutions extracted at 80 °C. This research highlights the potential of DPP as a functional ingredient in the food industry, creating a protein-polyphenol complex that reduces tea's astringency while maintaining its unique flavor profile, thus offering a novel approach to enhance tea beverages.

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  • In this work, the spectroscopy of epigallocatechin-3-gallate (EGCG) and EGCG bonded to 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) (DPPG) lipid is studied both experimentally by combining high-resolution vacuum ultraviolet (VUV) photo-absorption measurements in the 4.0-9.0 eV energy range and by theoretical calculations using density functional theory (DFT) methodology. There is a good agreement between the experimental and theoretical data, and the inclusion of the solvent both implicitly and explicitly further improves this agreement. For all experimentally measured absorption bands observed in the VUV spectra of EGCG in water, assignments to the calculated electronic transitions are provided. The calculations reveal that the spectrum of DPPG-EGCG has an intense peak around 150 nm, which is in accordance with experimental data, and it is assigned to an electron transfer transition from resorcinol-pyrogallol groups to different smaller groups of the EGCG molecule. Finally, the increase in absorbance observed experimentally in the DPPG-EGCG spectrum can be associated with the interaction between the molecules.

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  • Ferroptosis is a regulated cell death process linked to various diseases. This study explored whether Epigallocatechin-3-gallate (EGCG), a tea-derived antioxidant, could regulate ferroptosis to alleviate dextran sulfate sodium (DSS)-induced colitis.

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  • EGFR is frequently overexpressed in non-small cell lung cancer, and EGFR plays a crucial role in the occurrence and progression of malignant tumors. Currently, drug resistance often develops following treatment with EGFR tyrosine kinase inhibitors, such as erlotinib and gefitinib. Therefore, It is essential to investigate new compounds that can effectively target EGFR overexpression. The polyphenols epigallocatechin-3-gallate (EGCG), found in tea, have demonstrated anti-cancer properties. In this study, we linked EGCG and erlotinib through a click reaction using polyglycol to form an EGCG-erlotinib conjugated compounds (EGCG-Erls). We then explored its biological activity through various experiments. The results indicated that the compound 10 exhibited a superior inhibitory effect on NCI-H1975 cells, reduced their cloning and migratory capabilities, promoted cell apoptosis, and inhibited cell cycle progression. Furthermore, it was observed that compound 10 can bind to the EGFR protein and effectively inhibit the expression of phosphorylated EGFR (p-EGFR) and its downstream signaling proteins. Overall, the study suggests that compound 10 may induce apoptosis and inhibit cell proliferation via the EGFR signaling pathway, providing a promising avenue for the development of new EGFR inhibitors.

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  • M. Moradzadeh, A. Roustazadeh, A. Tabarraei, S. Erfanian, and A. Sahebkar, "Epigallocatechin-3-Gallate Enhances Differentiation of Acute Promyelocytic Leukemia Cells via Inhibition of PML-RARα and HDAC1," Phytotherapy Research 32, no. 3 (2018): 471-479, https://doi.org/10.1002/ptr.5990. The above article, published online on 29 November 2017 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Angelo A. Izzo; and John Wiley and Sons Ltd. The retraction has been agreed upon following an investigation into concerns raised by a third party, which revealed inappropriate image panel duplications between this article (Figure 4 a, b) and other articles published by an overlapping group of authors, in which the images represent different experimental conditions. The explanation provided by the authors could not address these concerns. Thus, the editors have lost confidence in the presented data and consider the conclusions of this manuscript substantially compromised. A. Sahebkar disagrees with the retraction, the other co-authors remained unresponsive.

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