Immobilization of Laccase on Hybrid Super-Structured Nanomaterials for the Decolorization of Phenolic Dyes

Michaela Patila,Lampros Kortessis,Georgia Potsi,Dimitrios Gournis,Haralambos Stamatis,Antonios Kouloumpis,Panagiotis E Athanasiou

doi:10.3390/pr10020233

Abstract

In the present work, hybrid super-structured nanomaterials were synthesized by the combination of smectite nanoclays with various carbon-based nanomaterials (graphene oxide, carbon nanotubes and adamantylamine) and were used as nanosupports for the covalent and non-covalent immobilization of laccase from Trametes versicolor (TvL). TvL was successfully immobilized on these hybrid nanomaterials, achieving high immobilization yields (up to 85%), while its conformation remained unaltered upon immobilization. The apparent kinetic constants Vmax and Km of the immobilized enzymes strongly depended on the immobilization procedure and the composition of hybrid nanomaterials. Immobilized TvL preserved up to 50% of its initial activity after 24 h of incubation at 60 °C, while free enzyme was totally deactivated. The TvL-hybrid nanomaterials bioconjugates were efficiently applied for the degradation of various synthetic dyes, exhibiting excellent decolorization capacity, as well as high reusability (up to 11 successive catalytic cycles), providing insights into the use of these bionanoconjugates on applications with environmental, and industrial interest.

Highlights

Academic Editors: Lai-Chang Zhang, Dyes are chemical compounds that are used extensively in textile and printing industry [1,2]
Immobilized Trametes versicolor (TvL) on Clay-carbon nanotubes (CNTs) and Clay-Graphene oxide (GO) was able to catalyze the decolorization of methyl orange, with decolorization yields of 56.5 and 47.6%, respectively, after
The results indicated decolorization of synthetic dyes. that the immobilization of TvL on hybrid nanomaterials resulted in the formation of robust biocatalysts that were capable of repeatable use for the decolorization of synthetic dyes

Summary

Introduction

Academic Editors: Lai-Chang Zhang, Dyes are chemical compounds that are used extensively in textile and printing industry [1,2]. Dye decomposition results in the production of several toxic substances which are released in the environment through waste effluents, causing toxic, mutagenic or carcinogenic problems [3,4]. Dye degradation or modification of the produced by-products is of critical significance. An alternative and environmental-friendly procedure relies on enzymatic treatment, as the products of enzymatic degradation are less toxic than the pristine synthetic dyes and they can be utilized by different natural organisms [7,8]. Fungal and microbial laccases have been widely explored towards their use in textile water treatment for dye decolorization and detoxification, via degradation or polymerization reactions, due to their oxidation power and ability to oxidize different chemical compounds [10]

Methods

Results

Conclusion