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

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.

Immobilization of Horseradish Peroxidase on Magnetite-Alginate Beads to Enable Effective Strong Binding and Enzyme Recycling during Anthraquinone Dyes’ Degradation

“…The FTIR spectra of MAB and HRP-MABs show a peak at 520 cm −1 due to Fe-O stretching frequency, while the peaks at 1590 and 1594 are shifted from 1632 cm −1 due to O-H bending and stretching vibrations which are attached to the surface of iron atoms [68]. The -OH stretching of HRP loaded microbeads is shifted to lower frequency (3364 cm −1 ), which is due to the electrostatic attraction between the C=O group of polymer matrix and -NH 2 group of HRP, which confirms that the HRP has been successfully loaded into microbeads [69]. New peaks at 622, 467 and 419 cm −1 are observed due to Fe-O group, confirming that the Mags are successfully loaded in the microbeads [70].…”

Recent Strategies and Applications for l-Asparaginase Confinement

“…Confinement of enzymes allows their continuous use while they are physically or chemically confined or localised in a certain defined area of the support, maintaining their structural integrity and exhibiting better catalytic activity [63][64][65]. Therefore, the choice of the support and enzyme confinement technique should take into account the nature of the enzyme, namely its biochemical and kinetic properties, the nature and type of the support and the purpose of application [66][67][68][69][70].…”

New Lead Discovery of Herbicide Safener for Metolachlor Based on a Scaffold-Hopping Strategy

“…To minimize toxicity caused by herbicides, crop plants have evolved their own protective mechanisms, for instance, the antioxidant system that is comprised of a series of enzymes, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) [47][48][49]. These antioxidant enzyme activities have also been reported to be associated with herbicide tolerance in crop plants [28].…”

“…As dichlormid has been reported to pose potential risks to aquatic organisms, such as fish, we further evaluated the acute toxicity (96 h) of 2k, 4k, and dichlormid on zebrafish embryo; a model frequently used to evaluate the toxicity of various compounds to aquatic organisms [52,53]. To minimize toxicity caused by herbicides, crop plants have evolved their own protective mechanisms, for instance, the antioxidant system that is comprised of a series of enzymes, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) [47][48][49]. These antioxidant enzyme activities have also been reported to be associated with herbicide tolerance in crop plants [28].…”