1. Department of Chemical Engineering, Chonbuk National University, 664-14 Duckjin-dong, 1Ga Deokjin-Gu, Jeonju 561-756, South Korea
2. Department of Microbiology, Chungbuk National University, 52 Naesudong-Ro, Seowon-Gu, Cheongju 361-763, South Korea