1. Department of Food and Nutrition, Faculty of Agriculture, Kinki University, Nara 631-0052 Japan.
2. Kyoto Bunkyo Junior Collage, Kyoto 611-0041 Japan.
3. Department of Biochmical Science and Technology, Faculty of Agriculture, Kagoshima University, Kagoshima 890-0065 Japan.
4. Corresponding author. Phone: +81-742-43-1511; Fax: +81-742-43-2252; Email: mitunaga@nara.kindai.ac.jp