title: A novel assay method for theanine synthetase activity by capillary electrophoresis.
abstract: The determination of theanine has been performed by micellar electrokinetic capillary chromatography (MECC) using 2,4-dinitrofluorobenzene (DNFB) as a derivative reagent. To achieve the separation, a fused-silica capillary column was used with a borax buffer at 0.03 mol/L pH 9.8 (containing Brij35 and isopropanol) at 17 degrees C with detection wave length at 360 nm. The factors affecting the efficiency of the sample separation were examined simultaneously. A 40-min reaction at 35 degrees C between l-glutamate and ethylamine (with Tris-HCl buffer, pH 7.5) was investigated using the theanine synthetase from budding tea seeds. A novel method for the analysis of theanine synthetase activity based on MECC was established. The method shows mean recovery ranged from 87.1 to 105.3% and linearity ranged from 0.2 to 5.0 mmol/L.
authors.affiliation: Key Laboratory of Tea Biochemistry and Biotechnology, Ministry of Agriculture, Anhui Agricultural University, Hefei 230036, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Xiao-Chun
authors.initials: XC
authors.lastname: Wan
authors.forename: Zheng-Zhu
authors.initials: ZZ
authors.lastname: Zhang
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.forename: Zuo-Jun
authors.initials: ZJ
authors.lastname: Shen
mesh_terms: D019732:Amide Synthases / Q000032:analysis*; D028241:Camellia sinensis / Q000201:enzymology*; D004355:Drug Stability; D019075:Electrophoresis, Capillary / Q000379:methods*; D000077423:Polidocanol; D011092:Polyethylene Glycols; D036226:Seedlings / Q000201:enzymology; D013501:Surface-Active Agents
chemical_list: D013501:Surface-Active Agents; D000077423:Polidocanol; D011092:Polyethylene Glycols; D019732:Amide Synthases; C502361:theanine synthetase