SINGLE CELL PROTEIN-PRODUCTION ON C-1-COMPOUNDS - THE BIOEFFICIENCY

Pertaining to the optimal SCP production from one-carbon compounds, a theory is presented to support that the reasons for the unusual behavior of biomass yields in methyltrophs are kinetic rather than biosynthetic. The theory stresses the branching of the carbon flow toward either carbon dioxide or biomass and explains easily why yields change with dilution rate, temperature, pH, and other culture conditions, although the actual efficiency remains unchanged. The various available methods for assessing the bioenergetics of a process are discussed, with a view to derive useful conclusions from existing data and to design optimally future experiements. Thus, comparisons of computed to experimental yields suggest that the P/O ratio for methanol oxidation is 1, that for formaldehyde oxidation to formate 1 or 3, and the one for formate oxidation possibly 3.