Harnessing Glycerol From Biodiesel Fuel Production To Obtain Valuable Industrial Compounds

FIGUEROA CM; PIATTONI CV; ASENCIÓN DIEZ MD; COMELLI R; GUERRERO SA; BECCARÍA AJ; IGLESIAS AA

Tucumán, Argentina

Congreso; XLV Reunión Anual de la SAIB; 2009

SAIB

Glycerol (Gro) has many appliances in the cosmetic, food, and pharmaceutical industries. However, Gro has become an inexpensive carbon source due to its generation as inevitable byproduct of biodiesel production, a process with outstanding growing within the last decade. In addition, the excess of Gro has environmental problems since it is not innocuous and its disposalturns complex. Thus, conversion of low-priced Gro streams to higher value products, such as 1,3-propanediol or dihydroxyacetone (DHA), has been proposed as relevant biorefinery strategies. Many organisms are able to metabolize Gro, and their enzymes are key targets in the bioconversion of this compound. In this work we have cloned and expressed the gene encoding for Gro dehydrogenase (GroDHase) in Escherichia coli. The enzyme converts Gro into DHA. The recombinant enzyme was purified to near homogeneity either by IMAC or heat shocktreatment. We have analyzed the activity assay conditions and determined the S values for both substrates, NAD+ (0.5 mM) and 0.5 Gro (100 mM). The maximum activity was reached at pH 11.0 and 40 ºC. NH Cl was found to be an activator of GroDHase, reducing 4 (4-fold) the S for Gro and increasing (1.5-fold) the V . Gro waste 0.5 max derived from biodiesel production was an effective substrate for the enzyme, which supports the biotechnological application of therecombinant GroDHase.