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Antioxidant properties and application information
Published in Roger L. McMullen, Antioxidants and the Skin, 2018
Theaflavins are found in black tea and have antioxidant, anti-carcinogenic, and anti-pathogenic properties. While epicatechins are associated with green tea, theaflavins are found in black tea. The four principle compounds in the theaflavin class are theaflavin, theaflavin-3-gallate, theaflavin-3′-gallate, and theaflavin-3,3′-digallate. The antioxidant activity of these compounds comes from their free radical scavenging capability (hydroxyl groups) and the ability to chelate metal ions.
Nutritional Ergogenic Aids: Introduction, Definitions and Regulatory Issues
Published in Ira Wolinsky, Judy A. Driskell, Nutritional Ergogenic Aids, 2004
Ira Wolinsky, Judy A. Driskell
theaflavins (theaflavin, theaflavin-3-gallate, theaflavin 3-gallate and theafla-vin-3,3’- digallate) and thearubigens. Thus, the major polyphenols in black tea are theaflavins and thearubigens. Theaflavins are responsible for the taste and reddish color of black tea, while thearubigens are the most abundant phenolic fraction in black tea. Unlike green tea, catechins constitute only 9% of the dry weight of black tea.7,8 The manufacturing of oolong tea is initially similar to that of black tea. After the leaves have been rolled, they are fired to terminate the oxidation. This results in a partially fermented tea that consists of both green tea catechins, black tea theaflavins and possibly thearubigens.7 Fermentation of black and green tea leads to important differences in the polyphenlic composition of tea leaves.8
Plant-Derived Natural Non-Nucleoside Analog Inhibitors (NNAIs) against RNA-Dependent RNA Polymerase Complex (nsp7/nsp8/nsp12) of SARS-CoV-2
Published in Journal of Dietary Supplements, 2023
Sreus A. G. Naidu, Ghulam Mustafa, Roger A. Clemens, A. Satyanarayan Naidu
Theaflavin and Theaflavin gallate, the black tea polyphenols, show broad‐spectrum antiviral activity (109). Theaflavin 3,3′-digallate (TF3), Theaflavin 3-gallate (TF2a) and Procyanidin B2 inhibit specific targets of SARS-CoV-2 and considered as promising intervention candidates for COVID-19 management (108). TF3 (ΔG = −14.92 kcal/mol), Procyanidin B2 (ΔG = −11.68 kcal/mol) and TF2a (ΔG = −10.90 kcal/mol) exhibit high binding affinities toward RdRp of SARS-CoV-2 with low docking scores (110). Theaflavin and its derivatives from traditional Chinese medicine were docked into the catalytic pocket near the active site of RdRp in SARS‐CoV‐2 (ΔG = −9.11 kcal/mol), SARS‐CoV ((ΔG = −8.03 kcal/mol), and MERS‐CoV ((ΔG = −8.26 kcal/mol). Theaflavin forms H-bonds and π‐cation interaction with Arg553 in the catalytic pocket of SARS‐CoV‐2 RdRp complex. Theaflavin also inhibits the RdRp activity via blocking the active site in the enzymatic scaffold (111).
Study on mechanism of low bioavailability of black tea theaflavins by using Caco-2 cell monolayer
Published in Drug Delivery, 2021
Fengfeng Qu, Zeyi Ai, Shuyuan Liu, Haojie Zhang, Yuqiong Chen, Yaomin Wang, Dejiang Ni
As a fully fermented tea, black tea is characterized with red liquor, red leaves, and sweet taste, and the fermentation process is crucial for the formation of its unique flavor and health effect due to the generation of theaflavins, thearubigins, and theabrownins. Theaflavins, the oxidation products of a pair of epimerized catechins, are responsible for the golden color and astringent taste of black tea (Wan, 2003). Furthermore, theaflavins, especially the gallated theaflavins, were found to be positively correlated with the bioactivities of black tea (Qu et al., 2020). In black tea, theaflavins are primarily composed of four monomers: theaflavin (TF), theaflavin-3-gallate (TF3G), theaflavin-3′-gallate (TF3’G), and theaflavin-3, 3′-digallate (TFDG), which vary in the position and number of galloyl moiety. The hydroxyl groups attached to the theaflavin skeleton and galloyl moiety enable theaflavins to effectively scavenge free radicals and promote the various bioactivities of theaflavins (Xie et al., 2018). For instance, theaflavins can suppress the adhesion and invasion of hepatoma cells by scavenging hydroxyl radicals and reactive oxygen species (ROS) (Zhang et al., 2000). Additionally, theaflavins can trigger a reduction of ROS in human colon adenocarcinoma cancer cells due to their excellent radical-scavenging ability (Tan et al., 2019). Furthermore, theaflavins are reported to develop resistance against bacteria, virus, inflammation, hyperglycemia, and cardiovascular disease (Liu et al., 2013). As one of the major naturally functional components in black tea, theaflavins have a promising prospect of clinical application.
Theaflavin-Containing Black Tea Extract: A Potential DNA Methyltransferase Inhibitor in Human Colon Cancer Cells and Ehrlich Ascites Carcinoma-Induced Solid Tumors in Mice
Published in Nutrition and Cancer, 2021
Ritwija Bhattacharya, Ranodeep Chatterjee, Abul Kalam Azad Mandal, Aniruddha Mukhopadhyay, Soumalee Basu, Ashok Kumar Giri, Urmi Chatterji, Pritha Bhattacharjee
It was estimated that from 100 g of tea leaves (Tata tea Gold), 2 g of TF extract was obtained. The total phenolic content of TF extract was found to be 702GAE mg/g. The identification of theaflavin extract was done by comparing retention times of the individual theaflavin fractions in the reference vs. tested solution (qualitative analysis). UPLC analysis showed the presence of theaflavins (TF-1), theaflavin-3-gallate (TF-2), theaflavin-3′-gallate (TF-3), and Theaflavine-3, 3′-digallate (TF-4). The percentage of TF-1, TF-2, TF-3 and TF-4 were 4.8, 2.1, 2.7 and 58.44 respectively. Theaflavine-3, 3′-digallate was the major fraction found in the extract. Theaflavins showed a total purity percentage of 68.04.