Our group has developed an efficient biomass utilization technology based on intrinsic characteristics of coryneform bacteria. The so-called "growth-arrested bioprocess" has so far enabled elevated productivities of biofuels and green chemicals.

The cells are grown on a large scale and packed to very high densities in a reactor in order to maximize the catalyst/volume ratio at the production stage. Sugars are subsequently added to initiate bioconversion as a substrate under oxygen limited condition; the tight packaging effectively ceases growth of the bacteria while keeping them metabolically active. As a result, the target chemical is produced by growth-arrested cells, with a larger share of the substrate being converted into useful products without any additional natural rich medium or external energy. The key to achieving high efficiency and high productivity is the effective separation of the microbial growth phase from the production phase of the target compound. This manner of using bacterial cells as if they were simple chemical catalysts enables one to produce large amounts of chemicals in short periods of time, and unlike conventional bioprocesses, the productivities reached, expressed as space-time-yield (STY), are comparable to those of chemical processes.

Advantageous points in comparison with a conventional method of productions are outlined below.
1. High productivity (high yield, space saving, short period of time).
2. Cells in the reactor are reusable, leading to the reduction of production costs.
3. Free from fermentation inhibitors.

We hope biorefinery using the growth-arrested bioprocess contributes towards global warming prevention, environmental protection and construction of a sustainable society.