[The refining of liquid swine manure as a substrate for biotechnologic transformation processes]

Pure and mixed cultures of Clostridium Spec. were tested in sterile and nonsterile batch fermentations in order to increase the content of short chain fatty acid in different liquid swine manure substrates. Fatty acid concentrations of 15 g/l were reached by a thermochemical pretreatment of the substrates and the application of a mixed culture of Cl. acetobutylicum, Cl. butyricum and Cl. paraputrificum. The distributions of C2-C5 fatty acids were determined. The results represent the basis to intensify the process of the biotechnological conversion of liquid swine manure.