1. Division of Biomedical Food Research; National Institute of Health Sciences; Kamiyoga 1-18-1 Setagaya-ku Tokyo Japan
2. Department of Bacteriology; Osaka Prefectural Institute of Public Health; Nakamichi 1-3-69 Higashinari-ku, Osaka Osaka Japan
3. Department of Animal and Food Hygiene; Obihiro University of Agriculture and Veterinary Medicine; Nishi 2-11 Inada-cho Obihiro Hokkaido Japan
4. Department of Domestic Science; Kyoto Seibo College; Fukakusa taya-cho, Fushimi-ku, Kyoto Kyoto Japan
5. Division of Safety Information on Food; Drugs, and Chemicals, National Institute of Health Sciences; Kamiyoga 1-18-1 Setagaya-ku Tokyo Japan