Improving the performance of lipases in the full hydrolysis of residual coconut oil by immobilization on hydrophobic supports

Abstract

The effect of the immobilization via interfacial activation on hydrophobic supports of lipase A from Candida antarctica (CALA) and Eversa Transform 2.0 (ETL) in the hydrolysis of residual coconut oil is herein explored. Firstly, some important process parameters (biocatalyst content, substrates ratio, reactor temperature and stirring) were evaluated using the Taguchi method for both free biocatalysts. For free ETL, it was possible to reach full hydrolysis after 6 h under optimized reaction conditions (9 wt% of ETL, 1:2 (oil/water, w/w), 50 °C and 180 rpm). For free CALA, reaching full hydrolysis was not possible under the same optimized reaction conditions, even after 24 h of reaction. Then, ETL and CALA were immobilized by interfacial activation on a methacrylate macroporous resin particles containing octadecyl groups. After reaction conditions optimization by the Taguchi method, immobilized ETL (ETL@C18) reached full hydrolysis under the same optimized reaction conditions of free ETL, but in only 3 h. Immobilized CALA (CALA@C18), reached full hydrolysis (>99 %) after 24 hours under optimized reaction conditions which was not possible employing free CALA (56 %). Finally, under optimized reaction conditions, ETL@C18 retained 85 % of its initial activity after 10 consecutive hydrolysis cycles, whereas CALA@C18 retained less than 50 % of its initial activity after 5 consecutive hydrolysis cycles.