1. Department of Polymer Science & Engineering, Pusan National University, Busan 609-735, Korea
2. Department of Chemical Engineering, Pusan National University, San 30 Jangjeon 2-dong Geumjeong-gu, Busan 609-735, Korea
3. Department of Food Science and Biotechnology & Institute of Life Sciences and Resources, College of Life Sciences, Kyung Hee University, Yongin, Korea
4. MediGen Inc., 461-6 Jeonmin-Dong, Yuseong-Gu, Daejon 305-811, Korea