Lipase From Rhizomucor miehei Immobilized on Magnetic Nanoparticles: Performance in Fatty Acid Ethyl Ester (FAEE) Optimized Production by the Taguchi Method.

Katerine Da S Moreira,Maria C M Souza,Rodolpho R C Monteiro,Rafael M Freire,Fernando L Menezes,Lillian M U D Fechine,José C S Dos Santos,Lourembergue S De M Júnior,André L B De Oliveira,Thays N Da Rocha,Pierre B A Fechine,Juliano C Denardin,Sebastian Michea

doi:10.3389/fbioe.2020.00693

Abstract

In this communication, it was evaluated the production of fatty acid ethyl ester (FAAE) from the free fatty acids of babassu oil catalyzed by lipase from Rhizomucor miehei (RML) immobilized on magnetic nanoparticles (MNP) coated with 3-aminopropyltriethoxysilane (APTES), Fe3O4@APTES-RML or RML-MNP for short. MNPs were prepared by co-precipitation coated with 3-aminopropyltriethoxysilane and used as a support to immobilize RML (immobilization yield: 94.7 ± 1.0%; biocatalyst activity: 341.3 ± 1.2 Up–NPB/g), which were also activated with glutaraldehyde and then used to immobilize RML (immobilization yield: 91.9 ± 0.2%; biocatalyst activity: 199.6 ± 3.5 Up–NPB/g). RML-MNP was characterized by X-Ray Powder Diffraction (XRPD), Fourier Transform-Infrared (FTIR) spectroscopy and Scanning Electron Microscope (SEM), proving the incorporation and immobilization of RML on the APTES matrix. In addition, the immobilized biocatalyst presented at 60°C a half-life 16–19 times greater than that of the soluble lipase in the pH range 5–10. RML and RML-MNP showed higher activity at pH 7; the immobilized enzyme was more active than the free enzyme in the pH range (5–10) analyzed. For the production of fatty acid ethyl ester, under optimal conditions [40°C, 6 h, 1:1 (FFAs/alcohol)] determined by the Taguchi method, it was possible to obtain conversion of 81.7 ± 0.7% using 5% of RML-MNP.

Highlights

Lipases represent the most widely used class of enzymes in biotechnological applications and organic chemistry (Javed et al, 2018; Pinheiro et al, 2018; Souza et al, 2020), due to some unique properties, such as selectivity and mild reaction conditions (Miranda et al, 2014)
For the immobilization by adsorption (Fe3O4@APTES-RML), the immobilization yield was 94.7%, the theoretical activity was 458.0 U/g and the real derivative activity was 341.3 U/g, this allowed an activity of 74.5%, as can be seen in Table 2, which contains the values of the immobilization parameters for the other biocatalysts
The immobilization of lipase from Rhizomucor miehei (RML) onto magnetic nanoparticles coated with 3aminopropyltriethoxysilane produced the biocatalyst Fe3O4@APTES-RML (RML-MNPA)

Summary

Introduction

Lipases represent the most widely used class of enzymes in biotechnological applications and organic chemistry (Javed et al, 2018; Pinheiro et al, 2018; Souza et al, 2020), due to some unique properties, such as selectivity and mild reaction conditions (Miranda et al, 2014). Biodiesel is a renewable fuel made from biomass, such as plants (vegetable oils) or animals (animal fat) (dos Santos Silva et al, 2011; Chua et al, 2020; Singh et al, 2020) It is a mixture of methyl or ethyl esters of fatty acids (Tiwari et al, 2018; Zhong et al, 2020), produced by the transesterification and esterification reaction in the presence of a catalyst (Teo et al, 2016; Aguieiras et al, 2017), such as lipases (Ycel et al, 2012; Verdasco-Martín et al, 2016; Okoro et al, 2019; Moreira et al, 2020). The immobilization of lipases is used as a tool for enzyme for favoring recovery and reuse (Brady and Jordaan, 2009; Rodrigues et al, 2015; dos Santos et al, 2017) besides, it promotes an improvement in enzyme activity, selectivity or specificity, stability and purity, aside resistance to such inhibitors (Barbosa et al, 2013, 2015; Rios et al, 2018; Monteiro et al, 2019a; Bezerra et al, 2020)

Objectives

Methods

Results

Conclusion