1. Research & Development Group, Functional Food Ingredients Division, and Life Science Research Laboratories, Life Science RD Center, Kaneka Corporation, Takasago, Hyogo 676-8688, Japan, Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Science, The University of Tokyo, Tokyo 113-8657, Japan, and Functional Food Ingredients Division, Kaneka Corporation, 3-2-4 Nakanoshima, Kita-Ku, Osaka 530-8288, Japan