1. Faculty of Pharmaceutical Sciences, Toho University, Miyama 2-2-1, Funabashi, Chiba 274-8510, Japan, Department of Traditional Chinese Medicine, Heilongjiang Provincial Institute for Drug Control, Harbin 150001, People's Republic of China, and Department of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Tsukide 3-1-100, Kumamoto City, Kumamoto 862-8502, Japan