Nährstoffarme Emers-Fermentation terrestrischer Cyanobakterien zur Produktion biotechnischer Wertstoffe

• Applicants: Dr. Michael Lakatos; Professor Dr. Roland Ulber
• Subject Area: Biological Process Engineering
• Term: from 2009 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 158354519

Terrestrial cyanobacteria are characterized by a great variety of valuables, which differ fundamentally from aquatic organisms. At the moment, the exploitation of these valuables and the production of larger quantities of these metabolites are not realized because the cultivation technology is unavailable yet. Therefore, we developed a novel type of emerse photobioreactor, within the first period of the project, to cultivate this group of organisms in a quantity sufficient for their processing. For the first time, this novel emerse photobioreactor strikes a new path to access the metabolite spectrum of terrestrial cyanobacteria. The aim of the applied second project period is 1) to validate the developed analytics, 2) to optimize the production of cyanobacterial valuables by computer aided methods, as well as 3) to scale-up the emerse photobioreactor about a factor of ten. Apart from balancing the mass flow, the project aims to model the flow dynamics in the bioreactor. Altogether, this will allow the final characterization of this novel emerse photobioreactor.This developed photobioreactor is ideally to satisfy the cultivation requirements of terrestrial cyanobacteria. On the one hand, the fibre optics (glass rods), enclosed in the reactor, serves as colonizing surfaces for the organisms, and on the other hand the adherent growing organisms and their growth zones are optimally exposed to the supplied light. Moreover, the supplier of aerosol, integrated at the periphery of the reactor, provides water and nutrients enabling a nutrient-poor cultivation of the target microorganisms. The established geometry as well as the process control permit a cultivation which is highly adjusted to the production of valuables from terrestrial cyanobacteria. In this regard, the experimental set-up facilitates the induced production of specific valuables such as the pigment scytonemin by applying UV-A-radiation and desiccation as well as nitrogen depletion. Moreover, the optimization of exopolysaccharide production is forced, while its composition as well as its content will be modified by varying the supply of aerosol.

• DFG Programme: Research Grants
• Participating Person: Professor Dr.-Ing. Kai Muffler