Production of new nanobiocatalysts via immobilization of lipase B from C. antarctica on polyurethane nanosupports for application on food and pharmaceutical industries.

Nanobiocatalysts were produced via immobilization of CalB lipase on polyurethane (PU) based nanoparticles and their application on the synthesis of important industrial products was evaluated. Nanoparticles of polyurethane functionalized with poly(ethylene glycol) (PU-PEG) were synthetized through miniemulsion polymerization and the addition of crosslinking agents were evaluated. The nanoparticles were employed as support for CalB and the kinetic parameters were reported. The performance of new biocatalysts was evaluated on the hydrolysis reaction of p-NPB and on the enantioselective hydrolysis of (R,S)-mandelic acid. The esterification reaction was evaluated on the production of ethyl esters of Omega-3. The effect of poly(ethylene glycol) molar mass (400, 4000 or 6000 Da)on the biocatalyst activity was also analyzed. The PU-PEG6000-CalB showed the highest value of the kinetic parameters, highlighting the high reaction rate. The addition of trehalose as crosslinking agent improved the thermal stability of the biocatalysts. PU-PEG400-CalB was the most active nanobiocatalyst, exhibiting a ethyl esters production of 43.72 and 16.83 mM.U -1 using EPA and DHA, respectively. The nanobiocatalyst was also applied in enantiomeric resolution of mandelic acid, showing promising enantiomeric ratios. The results obtained in this work present alternative and sustainable routes for the synthesis of important compounds used on food and pharmaceutical industries.

Characterization of a tannase from Emericella nidulans immobilized on ionic and covalent supports for propyl gallate synthesis.

The extracellular tannase from Emericela nidulans was immobilized on different ionic and covalent supports. The derivatives obtained using DEAE-Sepharose and Q-Sepharose were thermally stable from 60 to 75 °C, with a half life (t50) >24 h at 80 °C at pH 5.0. The glyoxyl-agarose and amino-glyoxyl derivatives showed a thermal stability which was lower than that observed for ionic supports. However, when the stability to pH was considered, the derivatives obtained from covalent supports were more stable than those obtained from ionic supports. DEAE-Sepharose and Q-Sepharose derivatives as well as the free enzyme were stable in 30 and 50 % (v/v) 1-propanol. The CNBr-agarose derivative catalyzed complete tannic acid hydrolysis, whereas the Q-Sepharose derivative catalyzed the transesterification reaction to produce propyl gallate (88 % recovery), which is an important antioxidant.