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Black tea represents a major source of dietary phenolics among regular tea drinkers.
Free Radic Res. 2002 Oct; 36(10):1127-35.FR

Abstract

The phenolic composition and antioxidant activities [TEAC, ORAC, FRAP] of consumer brews (1 tea bag in 230 ml for 1 min) of seven different brands of black tea from the British market were investigated. The main phenolic compounds identified were epigallocatechin gallate, four theaflavins, as well as epicatechin gallate, theogallin (tentative assignment), quercetin-3-rutinoside and 4-caffeoyl quinic acid. Thearubigins represented an estimated 75-82% of the total phenolics. Further, polyphenol fractions were in decreasing order theaflavins, flavan-3-ols, flavonols, gallic acids and hydroxycinnamates. On average, a cup of a consumer brew of black tea is providing polyphenols at the level of 262mg GAE/serving, of which 65 mg were assigned to individual polyphenols. The antioxidant activity of black tea preparations is higher than that of most reported dietary agents on a daily basis. Correlations were observed between the antioxidant activities and the sum of all quantified polyphenols by HPLC analysis as well as with the total phenolics. Treatment of the black tea brew with simulated gastric juice resulted in a significant increase of the identified theaflavins implying a partial cleavage of thearubigins in the environment of the gastric lumen. Therefore, black tea can be considered to be a rich source of polyphenols and/or antioxidants.

Authors+Show Affiliations

Centre for Age-Related Diseases, Guy's, King's and St Thomas's School of Biomedical Sciences, King's College London, Guy's Campus, Hodgkin Building-3rd floor, London SE1 9RT, UK.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

12516885

Citation

Rechner, A R., et al. "Black Tea Represents a Major Source of Dietary Phenolics Among Regular Tea Drinkers." Free Radical Research, vol. 36, no. 10, 2002, pp. 1127-35.
Rechner AR, Wagner E, Van Buren L, et al. Black tea represents a major source of dietary phenolics among regular tea drinkers. Free Radic Res. 2002;36(10):1127-35.
Rechner, A. R., Wagner, E., Van Buren, L., Van De Put, F., Wiseman, S., & Rice-Evans, C. A. (2002). Black tea represents a major source of dietary phenolics among regular tea drinkers. Free Radical Research, 36(10), 1127-35.
Rechner AR, et al. Black Tea Represents a Major Source of Dietary Phenolics Among Regular Tea Drinkers. Free Radic Res. 2002;36(10):1127-35. PubMed PMID: 12516885.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Black tea represents a major source of dietary phenolics among regular tea drinkers. AU - Rechner,A R, AU - Wagner,E, AU - Van Buren,L, AU - Van De Put,F, AU - Wiseman,S, AU - Rice-Evans,C A, PY - 2003/1/9/pubmed PY - 2003/4/15/medline PY - 2003/1/9/entrez SP - 1127 EP - 35 JF - Free radical research JO - Free Radic Res VL - 36 IS - 10 N2 - The phenolic composition and antioxidant activities [TEAC, ORAC, FRAP] of consumer brews (1 tea bag in 230 ml for 1 min) of seven different brands of black tea from the British market were investigated. The main phenolic compounds identified were epigallocatechin gallate, four theaflavins, as well as epicatechin gallate, theogallin (tentative assignment), quercetin-3-rutinoside and 4-caffeoyl quinic acid. Thearubigins represented an estimated 75-82% of the total phenolics. Further, polyphenol fractions were in decreasing order theaflavins, flavan-3-ols, flavonols, gallic acids and hydroxycinnamates. On average, a cup of a consumer brew of black tea is providing polyphenols at the level of 262mg GAE/serving, of which 65 mg were assigned to individual polyphenols. The antioxidant activity of black tea preparations is higher than that of most reported dietary agents on a daily basis. Correlations were observed between the antioxidant activities and the sum of all quantified polyphenols by HPLC analysis as well as with the total phenolics. Treatment of the black tea brew with simulated gastric juice resulted in a significant increase of the identified theaflavins implying a partial cleavage of thearubigins in the environment of the gastric lumen. Therefore, black tea can be considered to be a rich source of polyphenols and/or antioxidants. SN - 1071-5762 UR - https://www.unboundmedicine.com/medline/citation/12516885/Black_tea_represents_a_major_source_of_dietary_phenolics_among_regular_tea_drinkers_ L2 - https://www.tandfonline.com/doi/full/10.1080/1071576021000006707 DB - PRIME DP - Unbound Medicine ER -