Microbial Conversion of Crude Glycerol to Dihydroxyacetone

Glycerol is increasingly being used as a versatile raw material within the biorefinery. However, it is very expensive to refine the crude glycerol to a high purity. In this study, the biotransformation of crude glycerol (79 % purity) using Gluconobacter oxydans spp. oxydans for the production of fine chemical dihydroxyacetone (DHA) was investigated. A conversion of up to 90 % with crude glycerol was demonstrated when using sorbitol as a secondary carbon source to enhance biomass production. A novel process for the recovery of DHA employing generation of foam, filtration and reverse osmosis, was developed. Using this strategy the protein content was reduced by up to 80 % and DHA recovery higher than 94 %.