Microbial biosensors for process and environmental control

For rapid and precise monitoring of the various factors involved in fermentation reactions and environment, it seems entirely sensible to employ the microorganisms themselves, which are highly sensitive to change in their environment. This review has touched upon some of the ways in which microbial sensors might be employed to monitor levels of fermentation substrates, reaction products, nutrients and antibiotics. This account has dealt almost entirely with those microbial sensors that are being investigated and developed in Japan for application to the monitoring of fermentation processes and environmental materials. Much work remains to be done. Sensors that work well under laboratory conditions do not always succeed when placed in industrial media, however, and basic research on sensors using microorganisms and new mutations with improved properties must be backed up by developmental modification and refinement. Despite many attractive properties, only few immobilized enzyme probes have yet been applied in commercial instruments. To date only a very limited number of enzyme-electrode based systems have been introduced. Nevertheless, these and other types of biosensor are indispensable for the efficient operation of numerous biotechnological processes.<>