1. ; National Food Research Institute; Ministry of Agriculture, Forestry and Fisheries; Kannondai 2-1-2 305-8642 Tsukuba, Ibaraki Japan
2. ; Department of Chemistry and Biotechnology; The University of Tokyo; 113-8656 Tokyo Japan
3. ; Institute Applied Biochemistry; University of Tsukuba; 305-8572 Ibaraki Japan