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In this study solid and liquid wastes from the olive oil processing industry were evaluated as substrates for Yarrowia lipolytica growth with the aim of lipase production. Olive mill wastewater and olive oil cake seemed to provide necessary nutrients and physical support for the yeast to grow and produce enzyme. The highest lipolytic activity of 850 IU dm-3 was achieved after 4 days of submerged cultivation in supplemented olive mill wastewater. In addition, olive oil cake appeared to be a convenient substrate for lipase production under solid state fermentation mode. Lipase production was further improved by media supplementation and/or change in physical settings of the experiment. However, the most significant improvement of lipase production under solid state fermentation was achieved by an alkaline treatment of the substrate (more than 10-fold) when the amount of produced lipase reached up to ~40 IU g-1 of substrate. [Projekat Ministarstva nauke Republike Srbije, br. E!6750 i br. III 46010]

Ethyl cinnamate, an ester known asflavor and fragrance compound,has been synthesized using two immobilized bioreactor systems, batchand fluidized bed bioreactors. The enzyme used for this synthesisis a commercial lipase B preparation, Novozyme 435. Initial kineticstudies were conducted in both employed bioreactor configurations,and kinetic constants were obtained. Several models were tried forfitting of experimental data, but the best fit, for both bioreactors,was obtained when the ping-pong bi-bi mechanism was used. Interestinglyenough, ethanol inhibition occurred in batch bioreactor, but it didnot exist in the fluidized bed bioreactor. Solid–liquid masstransfer coefficients were calculated for both bioreactors to determinewhether mass transfer limitations existed in either of these systems.The calculation of Damköhler numbers and Thiele modulus confirmedthat mass transfer limitations had no effect on the overall reactionin both bioreactors. [ABSTRACT FROM AUTHOR]