TY - JOUR
T1 - Biocatalytic degradation of reactive blue 221 and direct blue 297 dyes by horseradish peroxidase immobilized on iron oxide nanoparticles with improved kinetic and thermodynamic characteristics
AU - Kalsoom, Umme
AU - Khalid, Nasira
AU - Ibrahim, Affaf
AU - Ashraf, Syed Salman
AU - Bhatti, Haq Nawaz
AU - Ahsan, Zainab
AU - Zdarta, Jakub
AU - Bilal, Muhammad
N1 - Funding Information:
The authors would like to thank the Higher Education Commission (HEC), Islamabad, Pakistan for funding under NRPU project No. 9914/Punjab/NRPU/R&D/HEC/2017 . The research leading to these results has received funding from the Norwegian Financial Mechanism 2014-2021 under the Project number 2020/37/K/ST8/03805 . Khalifa University is graciously acknowledged for partially supporting this work under the international collaboration project awarded to Syed Salman Ashraf and Muhammad Bilal ( CIRA-2020-046 ).
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2023/1
Y1 - 2023/1
N2 - In present study, we describe the biodegradation of direct blue (DB) 297 and reactive blue (RB) 221 by immobilizing horseradish peroxidase (HRP) isolated from fresh leaves of Moringa Oliefera on iron oxide nanoparticles. Iron oxide nanoparticles were synthesized by co-precipitation method and showed a maximum immobilization efficiency of 87%. The surface topography of iron oxide nanoparticles was envisaged by scanning electron microscopy (SEM), results showed that magnetic nanoparticles (MNPs) were in the form of aggregates having size of 1 μm. Furthermore, immobilization was confirmed via functional group identification performed by Fourier transformed infrared spectroscopy (FTIR). Immobilization phenomena displaced the optimum temperature from 35 °C to 50 °C moreover, pH optima were altered from 5.0 to 7.0. Vmax and Km for free and immobilized HRP, were 303 U/mg and 1.66 mM and 312 U/mg and 1.94 mM, respectively. Enzymatic thermodynamic measurements (ΔH*, ΔS*, Ea, ΔG*) were also evaluated for immobilized HRP and its free counterpart. Optimum degradation of reactive blue (RB) and direct blue (DB) 297 with free and immobilized HRP was observed at pH 5 and at temperature 40 °C respectively. The removal efficiency of DB 297 and RB 221 with free HRP was 75% and 86% while with immobilized HRP was 81% and 92% respectively. Furthermore, biodegradation of reactive blue (RB) 221 and direct blue (DB) 297 with immobilized and free biocatalyst was also investigated by Fourier transform infrared spectroscopy (FTIR) by identification of groups involved in dye degradation. FTIR results confirmed the 100% degradation of dyes. Immobilized HRP retained significant catalytic activity after five consecutive cycles of dye degradation. In conclusion, Fe3O4 nanoparticles are promising and environmentally friendly media for enzyme immobilization. Moreover, immobilized HRP showed more thermal stability, pH stability and higher dye degradation efficiency as compared to free HRP. Furthermore, the immobilized HRP, economically more convenient and easily removable from reaction media. Owing to its thermal stability, ease of separation from reaction media and reusability, the magnetically separatable immobilized HRP can be exploited successfully for treatment of dye contaminated textile effluents.
AB - In present study, we describe the biodegradation of direct blue (DB) 297 and reactive blue (RB) 221 by immobilizing horseradish peroxidase (HRP) isolated from fresh leaves of Moringa Oliefera on iron oxide nanoparticles. Iron oxide nanoparticles were synthesized by co-precipitation method and showed a maximum immobilization efficiency of 87%. The surface topography of iron oxide nanoparticles was envisaged by scanning electron microscopy (SEM), results showed that magnetic nanoparticles (MNPs) were in the form of aggregates having size of 1 μm. Furthermore, immobilization was confirmed via functional group identification performed by Fourier transformed infrared spectroscopy (FTIR). Immobilization phenomena displaced the optimum temperature from 35 °C to 50 °C moreover, pH optima were altered from 5.0 to 7.0. Vmax and Km for free and immobilized HRP, were 303 U/mg and 1.66 mM and 312 U/mg and 1.94 mM, respectively. Enzymatic thermodynamic measurements (ΔH*, ΔS*, Ea, ΔG*) were also evaluated for immobilized HRP and its free counterpart. Optimum degradation of reactive blue (RB) and direct blue (DB) 297 with free and immobilized HRP was observed at pH 5 and at temperature 40 °C respectively. The removal efficiency of DB 297 and RB 221 with free HRP was 75% and 86% while with immobilized HRP was 81% and 92% respectively. Furthermore, biodegradation of reactive blue (RB) 221 and direct blue (DB) 297 with immobilized and free biocatalyst was also investigated by Fourier transform infrared spectroscopy (FTIR) by identification of groups involved in dye degradation. FTIR results confirmed the 100% degradation of dyes. Immobilized HRP retained significant catalytic activity after five consecutive cycles of dye degradation. In conclusion, Fe3O4 nanoparticles are promising and environmentally friendly media for enzyme immobilization. Moreover, immobilized HRP showed more thermal stability, pH stability and higher dye degradation efficiency as compared to free HRP. Furthermore, the immobilized HRP, economically more convenient and easily removable from reaction media. Owing to its thermal stability, ease of separation from reaction media and reusability, the magnetically separatable immobilized HRP can be exploited successfully for treatment of dye contaminated textile effluents.
KW - Characterization
KW - Dye degradation
KW - Horseradish peroxidase
KW - Immobilization
KW - Iron oxide nanoparticles
UR - http://www.scopus.com/inward/record.url?scp=85141750789&partnerID=8YFLogxK
U2 - 10.1016/j.chemosphere.2022.137095
DO - 10.1016/j.chemosphere.2022.137095
M3 - Article
C2 - 36334735
AN - SCOPUS:85141750789
SN - 0045-6535
VL - 312
JO - Chemosphere
JF - Chemosphere
M1 - 137095
ER -
