1. Azusawa Research Laboratories, Institute for Consumer Healthcare, Yamanouchi Pharmaceutical Co., Ltd. 1-8, Azusawa 1-Chome, Itabashi-ku, Tokyo 174-8511, Japan,
2. Laboratory of Nutritional Biochemistry, Otsuma Women's University, Sanbancho 12, Chiyoda-ku, Tokyo 102-8357, Japan