DASGIP AG optimizes its cultivation system to conditions of anaerobic micro-organisms and thus facilitates biofuel development

DASGIP AG, a leading manufacturer of parallel bioreactor systems, has optimized its technology for the process development of anaerobic microorganisms via their parallel design. Through this type of parallel control and monitoring, a more efficient development of biofuels like bioethanol is facilitated. DASGIP will present these fermentation control systems during the Biotechnica 2007 in Hanover.

Bioethanol is produced by a variety of micro-organisms under anaerobic conditions, i.e. in the absence of oxygen. For biotechnical methods of fuel production to be competitive with conventional procedures, it is necessary to use such variants of micro-organisms whose enzymes can produce biofuels at low temperatures, with a high pH tolerance, and with minimal energy consumption. With this goal in mind, DASGIP has optimized its parallel bioreactor systems: The user can ferment and compare several different micro-organisms under the same conditions (screening), or the same micro-organism can be compared under different conditions (optimization). The system allows continuous monitoring of important variables such as pH value and redox potential, gassing parameters and temperature.

The separate measuring of pH and redox potential is particularly important. In anaerobic metabolism of micro-organisms a negative redox potential is essential for specific enzyme activities. As even small changes in pH can influence the redox potential, one can see how the pH value is an important parameter that must be monitored individually. DASGIP’s PH4RD4 module can measure redox potential and pH simultaneously and individually in four reactors. By controlling these conditions with very high precision, the identification of the ideal reaction parameters for the cells is simplified. The information density accelerates the selection of strains and the best fermentation parameters. In addition, the gassing module MF4 supplies the bioreactor with up to four input gasses. Each gas has its own independent lead, which can be selected as necessary. The user can even combine gasses that react with each other in the same gassing system and thus optimize the conditions of testing.

DASGIP’s parallel bioreactor systems are already used worldwide in industrial biotechnology. One example is in the field of enzyme technology and biocatalysis. Professor Mani Subramanian, Director of the Center for Biocatalysis and Bioprocessing at the University of Iowa, utilizes the DASGIP fermentation system in the field of enzyme technology: This is being done in two steps. First, the Pichia biomass and enzyme expression is optimized by monitoring and controlling pH, temperature, oxygen and enzyme induction by methanol. In a second step the product yield with the Pichia cells is maximized by “reaction engineering” in the DASGIP system. The enzyme system they are working with is glycolate oxidase. The research activities of Professor Dirk Weuster-Botz from the Technical University of Munich, Germany, which has already been presented by DASGIP, are addressed to the development of alternative procedures in industrial biotechnology as well. The project is supported by the Deutsche Bundesstiftung Umwelt (DBU, one of Europe's largest foundations promoting innovative and exemplary environmental projects). The goal is to develop a fermentation process for the industrial production of succinic acid in Sacharomyces cerevisiae. Succinic acid is an important chemical resource which is used widely in the pharmaceutical and chemical industry.