Immobilization of Low-Cost Alternative Vegetable Peroxidase (Raphanus sativus L. peroxidase): Choice of Support/Technique and Characterization.

Gabrielle Souza Da Silva Barbosa,Alini Tinoco Fricks,Maria Emanuela P S Oliveira,Ana Beatriz S Dos Santos,Cleide Mara Faria Soares,Osmar Calderón Sánchez

doi:10.3390/molecules25163668

Gabrielle Souza Da Silva Barbosa, Alini Tinoco Fricks + Show 4 more

Open Access

https://doi.org/10.3390/molecules25163668

Copy DOI

Abstract

In the present work the radish (Raphanus sativus L.) was used as the low-cost alternative source of peroxidase. The enzyme was immobilized in different supports: coconut fiber (CF), calcium alginate microspheres (CAMs) and silica SBA-15/albumin hybrid (HB). Physical adsorption (PA) and covalent binding (CB) as immobilization techniques were evaluated. Immobilized biocatalysts (IBs) obtained were physicochemical and morphologically characterized by SEM, FTIR and TGA. Also, optimum pH/temperature and operational stability were determined. For all supports, the immobilization by covalent binding provided the higher immobilization efficiencies—immobilization yield (IY%) of 89.99 ± 0.38% and 77.74 ± 0.42% for HB and CF, respectively. For CAMs the activity recovery (AR) was of 11.83 ± 0.68%. All IBs showed optimum pH at 6.0. Regarding optimum temperature of the biocatalysts, HB-CB and CAM-CB maintained the original optimum temperature of the free enzyme (40 °C). HB-CB showed higher operational stability, maintaining around 65% of the initial activity after four consecutive cycles. SEM, FTIR and TGA results suggest the enzyme presence on the IBs. Radish peroxidase immobilized on HB support by covalent binding is promising in future biotechnological applications.

Highlights

Peroxidases (EC 1.11.1.7) are enzymes that catalyze the oxidation of a wide variety of substrates dependent on H2 O2 [1]
The results report the immobilization of radish (Raphanus sativus L.) peroxidase in the coconut fiber (CF) and calcium alginate microspheres (CAMs) supports by physical adsorption (PA) and Molecules 2020, 25, x covalent binding (CB) techniques and in SBA-15/albumin hybrid (HB) support by the covalent binding (CB)
The effect of protein loading on a support the techniques purpose of enzyme immobilization should be evaluated, especially when different supportsforand are investigated

Summary

Introduction

Peroxidases (EC 1.11.1.7) are enzymes that catalyze the oxidation of a wide variety of substrates dependent on H2 O2 [1]. Horseradish peroxidase (HRP) is the most studied [2,3] due to the numerous possibilities of applications, such as bioremediation, biosensors and diagnostic kits [4,5]. HRP presents considerable stability [6]. One strategy to break this barrier is to look for alternative plant peroxidases—similar to HRP—that can perform the same applications. Many studies focused on applications for alternative peroxidases have been developed: peroxidase from guinea grass leaves as biosensor [8], turnip peroxidase for analytical and diagnostic kits [9], radish and turnip peroxidases in organic synthesis [10], cedar leaf peroxidase for decolorization of Molecules 2020, 25, 3668; doi:10.3390/molecules25163668 www.mdpi.com/journal/molecules

Methods

Results

Conclusion