1. Department of BioEngineering, Nagaoka University of Technology, Kamitomioka, Nagaoka, Niigata 940-21, Japan, School of Pharmaceutical Sciences, Nagasaki University, Bunkyo-machi, Nagasaki, Nagasaki 852, Japan, and Department of Applied Microbial Technology, Kumamoto Institute of Technology, Ikeda, Kumamoto, Kumamoto 860, Japan