1. Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyou-cho, Nagasaki 852-8521, and Bio-nutrition Division, Taiyo Kagaku Co. Ltd., 1-3 Takaramachi, Yokkaichi 510-0844, Japan