The author, Dr. M. Shoda, started his academic career with undergraduate, and graduate courses in Biochemical Engineering at the University of Tokyo, Tokyo, Japan. His Ph.D. thesis was on the modeling and computer simulation of product inhibition in microbial reactions under the supervision of Professor S. Aiba, who was a pioneer in Biochemical Engineering. This work on the introduction of computers to modeling was the first trial in the microbial world, and his scientific paper received 40th Anniversary Award for Papers with Special Impact on Biotechnology (John Wiley and Sons, Inc.). As assistant professor at Nagoya University, he gained experience in basic biochemistry and microbiology under the supervision of the late Professor S. Udaka, who was famous as the pioneer of producing amino acids using microbial reactions. He then moved to Tokyo Institute of Technology, where he concentrated on environmental biotechnology based on basic genetics and biochemistry, as well as computer control. As Director of the Research Laboratory of Resources Recycling Process, he supervised numerous graduate students who contributed to this book. He published more than 250 scientific papers, regarding isolation of several new microorganisms, including a new fungus that decomposes many toxic and colored chemicals by producing different unique enzymes, and a bacterium that converts ammonia directly to N2 gas without using conventional nitrification and denitrification processes at a 100-fold higher rate than the conventional method. He is active in research and application of microbial reactions as Professor Emeritus at Tokyo Institute of Technology.