1. Department of Life Sciences, National Chung Hsing University, Taichung 402, and School of Chinese Medicine, China Medical University, Taichung 404, Taiwan
2. Department of Animal Nutrition, Livestock Research Institute, Council of Agriculture, Tainan 712, Taiwan
3. Department of Molecular Biotechnology, Da-Yeh University, Changhwa 515, Taiwan
4. Program of Technology Management, Fu Jen Catholic University, Taipei County 242, Taiwan