Immobilization of porcine pancreatic lipase on poly-hydroxybutyrate particles for the production of ethyl esters from macaw palm oils and pineapple flavor

Abstract

Poly-hydroxybutyrate particles (PHB) were used as support to immobilize porcine pancreatic lipase (PPL). The biocatalysts prepared were tested in the synthesis of pineapple flavor by esterification of butanol and butyric acid in heptane medium, and in the synthesis of ethyl esters by transesterification of macaw palm pulp (MPPO) and macaw palm kernel (MPKO) oils with ethanol in solvent-free systems. The effect of protein loading on the biocatalyst activity was assessed in olive oil hydrolysis. Maximum hydrolytic activity of 292.8±8.60IU/g was observed. Langmuir isotherm model was applicable to the adsorption of PPL on PHB particles. Maximum immobilized protein amount was 24.3±1.70mg/g. The optimal pH and temperature in hydrolysis reaction for the immobilized PPL were at pH 8.5 and 50°C, while for the crude PPL extract were at pH 8.0 and 45°C. Immobilized PPL exhibited full hydrolytic activity after 2h of incubation in non-polar solvents. In esterification reaction, optimal conversion was around 93% after 2h of reaction. After six esterification cycles, the biocatalyst retained 63% of its initial activity. The biocatalyst prepared attained transesterification yield of 50% after 48h of reaction for MPKO and 35% after 96h of reaction for MPPO.