W Łuczaj1, E Skrzydlewska. 1. Department of Analytical Chemistry, Medical University of Białystok, Mickiewicza 2a, P.O. Box 14, 15-230 Białystok 8, Poland.
Abstract
BACKGROUND: Black tea, obtained by tea leaves fermentation, is an oxidized product and contains mainly multimeric polyphenols, whose biological activity is not well documented. This paper reviews the available literature on the effects of black tea on health with a focus on its antioxidative activity. METHODS: A review of the different issues and studies relating to composition, manufacturing, and antioxidative effects of black tea and its components in vitro as well as in vivo is presented. RESULTS: It is generally believed that polyphenols such as theaflavins and thearubigins as well as catechins as major constituents of black tea are mainly responsible for antioxidant actions. Antioxidative properties of black tea are manifested by its ability to inhibit free radical generation, scavenge free radicals, and chelate transition metal ions. Black tea, as well as individual theaflavins, can influence activation of transcription factors such as NFkappaB or AP-1. Theaflavins have been also proved to inhibit the activity of prooxidative enzymes such as xanthine oxidase or nitric oxide synthase. CONCLUSIONS: Black tea consumed throughout the world is believed to be not only a popular beverage but also an antioxidative agent available in everyday life.
BACKGROUND:Black tea, obtained by tea leaves fermentation, is an oxidized product and contains mainly multimeric polyphenols, whose biological activity is not well documented. This paper reviews the available literature on the effects of black tea on health with a focus on its antioxidative activity. METHODS: A review of the different issues and studies relating to composition, manufacturing, and antioxidative effects of black tea and its components in vitro as well as in vivo is presented. RESULTS: It is generally believed that polyphenols such as theaflavins and thearubigins as well as catechins as major constituents of black tea are mainly responsible for antioxidant actions. Antioxidative properties of black tea are manifested by its ability to inhibit free radical generation, scavenge free radicals, and chelate transition metal ions. Black tea, as well as individual theaflavins, can influence activation of transcription factors such as NFkappaB or AP-1. Theaflavins have been also proved to inhibit the activity of prooxidative enzymes such as xanthine oxidase or nitric oxide synthase. CONCLUSIONS:Black tea consumed throughout the world is believed to be not only a popular beverage but also an antioxidative agent available in everyday life.
Authors: Sareh Doustfatemeh; Mohammad Hadi Imanieh; Abdolali Mohagheghzade; Mohammad M Zarshenas; Zahra Torkamani; Gholamhossein Yousefi; Saman Farahangiz; Alireza Salehi Journal: J Evid Based Complementary Altern Med Date: 2016-06-19
Authors: Aleksandra S Velićanski; Dragoljub D Cvetković; Siniša L Markov; Vesna T Tumbas Šaponjac; Jelena J Vulić Journal: Food Technol Biotechnol Date: 2014-12 Impact factor: 3.918
Authors: Barbara Szachowicz-Petelska; Izabela Dobrzyńska; Elżbieta Skrzydlewska; Zbigniew A Figaszewski Journal: Toxicol Mech Methods Date: 2008-06-23 Impact factor: 2.987