1. Research Center, Asahi Glass Co. Ltd, Yokohama, Kanagawa 221-8755, Japan
2. Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795, Japan
3. National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi Hiroshima, Hiroshima 739-0046, Japan
4. Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi Hiroshima, Hiroshima 739-8526, Japan