Monday, July 25, 2011
Grand Ballroom, 5th fl (Sheraton New Orleans)
Conversion of glycerol into succinic acid has been proposed as a way of recycling a rather abundant byproduct of the biodiesel industry, into a higher value chemical platform. Many natural succinic acid microbial producers have been isolated and are able to reach very high succinic acid titers. Furthermore, bioproduction of succinic acid has been showed to be very efficient using most of existing carbon sources. However, utilisation of glycerol by these succinogens, in particular A. succinogenes, remains to be improved in order to be competitive, or even comparable with glucose, for instance. Even though glycerol utilisation is not efficient enough in terms of volumetric productivity or specific growth rate, formation of by-products during glycerol fermentation is rather limited, which should simplify further downstream purification and suggest the potential of glycerol for succinic acid production. The aim of this work is to implement a high cell density fermentation process in order to significantly increase glycerol consumption rate and succinic acid volumetric productivity. A precise kinetic model will be initially developed using data from various batch cultivations. The model will be used to improve succinic acid volumetric productivity in continuous high cell density systems.