title: Effect of electrolyzed reduced water on chiral theanine and polyphenols in tea.
abstract: Pure D/L-theanine enantiomers were synthesized separately, and SEM was used for their crystal-structure observation. The novel enantiomeric separating method by HPLC was established using the chiral selector of β-CD in the mobile phase. Green tea, white tea, oolong tea, black tea and Pu-erh tea were tested for theanine enantiomers by different degrees of fermentation. The significantly higher d-enantiomeric proportion of theanine was found in white tea than the others, which was probably due to its specific processing step of withering. The effect of electrolyzed reduced water (ERW) on enantiomeric theanine and polyphenols in tea was explored. There was no change of theanine, but rather a loss of ECG (epicatechin gallate) and an increasing amount of GA (gallic acid). ERW also reduced tea cream, which contains significant amount of polyphenols, indicating its potential application in the tea-beverage industry.
authors: School of Life Sciences and Technology, Tongji University, No. 1239 Siping Road, Shanghai 200092, People's Republic of China.
authors: Yusheng
authors: Y
authors: Zhao
authors: Ping
authors: P
authors: Li
authors: Ling
authors: L
authors: Ge
authors: Yan
authors: Y
authors: Wang
authors: Ting
authors: T
authors: Mo
authors: Xinping
authors: X
authors: Zeng
authors: Xiaodan
authors: X
authors: Wang
mesh_terms: D028241:Camellia sinensis / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D005971:Glutamates / Q000737:chemistry*; D010084:Oxidation-Reduction; D059808:Polyphenols / Q000737:chemistry*; D013237:Stereoisomerism; D013662:Tea / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D005971:Glutamates; D059808:Polyphenols; D013662:Tea; D014867:Water; C026166:theanine