Different organic components on silica hybrid matrices modulate the lipase inhibition by the glycerol formed in continuous transesterification reactions

Abstract Silica hybrid materials, functionalized via incorporation of three organic components: β-cyclodextrin (βCD), carboxymethyl-cellulose (CMC) and hydroxyethyl-cellulose (HEC) were synthesized by the sol–gel technique and results were compared to a well-defined matrix (silica–polyvinyl alcohol–SiO 2 –PVA) with respect to immobilizing Burkholderia cepacia lipase. The main objective was set to select organic components that can replace the PVA to obtain a hybrid composite with greater hydrophobic character, without compromising the remarkable features of SiO 2 –PVA. All the three selected compounds allowed obtaining matrices that presented similar textural and morphological properties and gave high activity (1451–1661 U g −1 ) and thermal stability (t 1/2  > 70 h) upon immobilization. Regarding glycerol affinity, all matrices had lower ability than SiO 2 –PVA to adsorb glycerol, with the SiO 2 –βCD matrix showing the lowest affinity due to the cyclic structure of the βCD. Transesterification reactions of palm kernel oil with ethanol mediated by B. cepacia immobilized on SiO 2 –βCD performed in a packed bed reactor under continuous flow confirmed the efficiency of the SiO 2 –βCD matrix in increasing the operational stability of system, revealing a half-life (t 1/2  = 1040 h), 2.5 times greater than that achieved in the same system using lipase immobilized on SiO 2 –PVA (t 1/2  = 430 h).