Higher fungi (Basidiomycetes, Ascomycetes) feed on by giving enzymes into their environment and thus decomposing organic material and absorbing the resulting nutrients. These outward secreted extracellular enzymes, the so-called secretome, allow even the degradation of lignified biomass (lignocellulose), whose cell walls consist of crosslinked macromolecules and which are not easily accessible for chemical degradation. A cooperative project of the University of Dortmund, the company Protagen AG and the Internationales Hochschulinstitut Zittau suceeded in making enzymes available for biotechnological fungal biomass degradation.
The extracellular enzymes of the two species of fungi were centrifuged, purified, concentrated and analyzed. Subsequently, characteristic key enzymes of the degradation of lignified biomass were produced as crude extract and successfully used for the degradation of finely ground rapeseed straw. A combination of these key enzymes with commercially available fungal enzymes provided first effective enzyme cocktails for this degradation process.
Use in large scale
Several tests within the project provide opportunities for the use of tailored enzyme cocktails on a large scale. Thus, straw and wood waste from agriculture, forestry and paper manufacturing could be degraded in a chemical-free way and made available for further recycling and energy recovery. Depending on the selected enzyme, for example special chemicals, bleached pulp for paper production and bioethanol production could be provided.
