▎ 摘　　要

Biobased ternary nanocomposites can stabilize enzymes for greater stability, catalytic activity and easy recovery. This study aimed to optimize biogenic silica/magnetite/graphene oxide nanocomposite supported Candida rugosa lipase (CRL/SiO2/Fe3O4/GO) for ethyl valerate (EV) synthesis and characterize the biocatalysts' physicochemical properties and operational stability. CRL conjugated-oil palm leaves-derived biogenic SiO2/Fe3O4/GO nanocomposite showed a maximum immobilized protein of 44.13 +/- 2.1 mg/g with a specific activity (534.87 +/- 9.5 U/mg), than free CRL (>= 700 U/mg). GL-A-SiO2/Fe3O4/GO exhibited the highest surface area (260.87 m(2)/g) alongside superior thermal stability in TGA/DTG. XRD revealed an amorphous SiO2 (crystallinity = 26.7%), while Fe3O4 existed as cubic spinel crystal (crystallinity = 90.2%). Taguchi Design-optimization found that CRL/SiO2/Fe3O4/GO best catalyzed the EV synthesis (90.4% in 3 h) at 40 celcius using 3 mg/mL of biocatalyst, valeric acid/ethanol molar ratio of 1:2, in 10% (m/v) molecular sieves with stirring in heptane at 200 rpm. EV production was confirmed by FTIR-(C=O: 1738 cm(-1) and C-O-C: 1174 cm(-1)) and GC-MS ([M]+ m/z = 130, C7H14O2). CRL/SiO2/Fe3O4/GO's reusability for 11 successive esterification cycles demonstrated the SiO2/Fe3O4/GO's exceptional hyperactivation and stabilization properties on immobilized CRL. These findings conveyed the SiO2/Fe3O4/GO's efficacy to alter CRL's physicochemical properties and operational stability for catalyzing higher yields EV. (C) 2021 The Society of Powder Technology Japan. Published by Elsevier BV and The Society of Powder Technology Japan. All rights reserved.