Enzymes, substrates and ionic liquids as a triad for potential development of efficient industrial processes

The present work is focused on technological solutions for enzymatic reactions in an industrial context with the support of ionic liquids in combination with organic solvents. Ionic liquids stand out for their unique physical-chemical properties that drive a large number of applications in different fields such as synthesis, catalysis, electrochemistry and nanotechnology. Their successful entrance in the enzymatic catalysis arena at the beginning of 2000, showed their potential as reaction medium. For several reactions the organic solvents were successfully replaced by pure ionic liquids generating higher yields and in some cases with proven increased enzymatic stability. This represents the starting point of the project that extended the usage of the ionic liquids for enzyme catalyzed reactions to biphasic systems, for possible new technological solutions, having SILP technologies as a model. The desired reaction takes place at the interface between an ionic liquid and an organic solvent as an immiscible mixture, being catalyzed by lipases, known to be active at the contact phase. The aim is to optimize the reaction system to favor the formation of the product mainly in the organic phase, in an attempt to avoid tedious separation steps, considered in many industrial processes as a bottle neck. The migration towards a particular phase is based on the partition of the compound of interest between the two corresponding solvents. Combination of several ionic liquids with organic solvents characterized by different polarities were set for analyzing the behavior of the substrates as well as for the products

The synovial proteome: analysis of fibroblast-like synoviocytes

The present studies were initiated to determine the protein expression patterns of fibroblast-like synovial (FLS) cells derived from the synovia of rheumatoid arthritis patients. The cellular proteins were separated by two-dimensional polyacrylamide gel electrophoresis and the in-gel digested proteins were analyzed by matrix-assisted laser desorption ionization mass spectrometry. A total of 368 spots were examined and 254 identifications were made. The studies identified a number of proteins that have been implicated in the normal or pathological FLS function (e.g. uridine diphosphoglucose dehydrogenase, galectin 1 and galectin 3) or that have been characterized as potential autoantigens in rheumatoid arthritis (e.g. BiP, colligin, HC gp-39). A novel uncharacterized protein product of chromosome 19 open reading frame 10 was also detected as an apparently major component of FLS cells. These results demonstrate the utility of high-content proteomic approaches in the analysis of FLS composition

A Monolithic Hybrid Cellulose-2.5-Acetate/Polymer Bioreactor for Biocatalysis under Continuous Liquid-Liquid Conditions Using a Supported Ionic Liquid Phase

Mesoporous monolithic hybrid cellulose-2.5-acetate (CA)/polymer supports were prepared under solvent-induced phase separation conditions using cellulose-2.5-acetate microbeads 8-14μm in diameter, 1,1,1-tris(hydroxymethyl)propane and 4,4′-methylenebis(phenylisocyanate) as monomers as well as THF and n-heptane as porogenic solvents. 4-(Dimethylamino)pyridine and dibutyltin dilaurate (DBTDL), respectively, were used as catalysts. Monolithic hybrid supports were used in transesterification reactions of vinyl butyrate with 1-butanol under continuous, supported ionic liquid-liquid conditions with Candida antarctica lipaseB (CALB) and octylmethylimidazolium tetrafluoroborate ([OMIM+][BF4-]) immobilized within the CA beads inside the polymeric monolithic framework and methyl tert-butyl ether (MTBE) as the continuous phase. The new hybrid bioreactors were successfully used in dimensions up to 2×30cm (V=94mL). Under continuous biphasic liquid-liquid conditions a constant conversion up to 96% was achieved over a period of 18days, resulting in a productivity of 58μmolmg-1(CALB)min-1. This translates into an unprecedented turnover number (TON) of 3.9×107 within two weeks, which is much higher than the one obtained under standard biphasic conditions using [OMIM+][BF4-]/MTBE (TON=2.7×106). The continuous liquid-liquid setup based on a hybrid reactor presented here is strongly believed to be applicable to many other enzyme-catalyzed reactions.</p