title: Variations of antioxidant properties and NO scavenging abilities during fermentation of tea.
abstract: Tea is known as one of the most popular beverages in the world, which is believed to be beneficial for health. The main components in tea will change a lot depending on the different processes of fermentation, and thus the effects of different teas on human health may differ. The aim of this study is to explore the varied abilities of reactive oxygen species (ROS) and nitric oxide (NO) scavenging during the fermentation of tea. In this study, we conducted the in vitro experiments which involved some reaction systems indicating the abilities of scavenging ROS and NO. We also investigated the effects of tea and their components (catechins, theabrownins, caffeine) on the intracellular levels of ROS and NO, using Raw 264.7 cells as the model. We found that regardless of whether it was out of cell system or in Raw 264.7 cells, the abilities of scavenging ROS would decrease during the fermentation of tea. Further, the post-fermented pu-erh tea showed the best effect on inhibiting the lipopolysaccharide (LPS)-induced production of NO. These findings indicated that the fermentation process caused a change of the components which might be due to the changes of their antioxidant properties and NO scavenging abilities.
authors.affiliation: Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, College of Life Science, Jilin University, Changchun 130012, China; E-Mails: xuyang759@yahoo.com.cn (Y.X.); zhzky@163.com (H.Z.); zhangmin2584652@yahoo.com.cn (M.Z.); lichunjie0821@163.com (C.-J.L.); a-xing_3@163.com (X.-Z.L.).
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.forename: Hang
authors.initials: H
authors.lastname: Zhao
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Chun-Jie
authors.initials: CJ
authors.lastname: Li
authors.forename: Xue-Zhen
authors.initials: XZ
authors.lastname: Lin
authors.forename: Jun
authors.initials: J
authors.lastname: Sheng
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000633:toxicity; D008070:Lipopolysaccharides / Q000633:toxicity; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D009569:Nitric Oxide / Q000737:chemistry / Q000378:metabolism*; D059808:Polyphenols / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000737:chemistry / Q000378:metabolism; D013662:Tea / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D008070:Lipopolysaccharides; D059808:Polyphenols; D017382:Reactive Oxygen Species; D013662:Tea; D009569:Nitric Oxide; D006861:Hydrogen Peroxide