1. Tea Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu 610066, P. R. China
2. TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu 610075, P. R. China
3. National Institute of Measurement and Testing Technology, Chengdu 610021, P. R. China