1. Laboratory of Health Science, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, Shizuoka 422-8526, Japan; Department of Chemistry and Biochemistry, Numazu College of Technology, 3600 Ooka, Numazu, Shizuoka 410-8501, Japan; and National Research Institute of Vegetables, Ornamental Plants and Tea, Ministry of Agriculture, Forestry and Fisheries, 2769 Kanaya, Shizuoka 428-8501, Japan