State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Science and Technology, Anhui Agricultural University, Anhui, PR China. Department of Clinical Nutrition, Affiliated Hospital of Jiangsu University, Jiangsu, PR China. Pritzker School of Medicine, University of Chicago, Chicago, IL, USA. State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Science and Technology, Anhui Agricultural University, Anhui, PR China. Email: yijun@ahau.edu.cn.