1. Sasaki Food Co., Ltd., 276 Sakai, Bungotakada, Oita 879-0615, Japan, Shizenshokken Co., Ltd., 293 Sakai, Bungotakada, Oita 879-0615, Japan, Department of Applied Molecular Biosciences, Nagoya University, Furo-cho, Chigusa-ku, Nagoya 464-8601, Japan, and Faculty of Education and Welfare Science, Oita University, 700 Dannoharu, Oita 870-1192, Japan