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Covalent immobilization of laccase on Fe3O4-graphene oxide nanocomposite for biodegradation of phenolic compounds

Rouhani Shamila, Azizi Shohreh, Maaza Malik, Mamba Bhekie, Msagati Titus A. M.

Environment Protection Engineering

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2021

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Vol. 47, nr 1

85--99

EN

Laccase from Trametes Versicolor (E.C. 1.10.3.2) was immobilized on the Fe3O4–graphene hybrid nanocomposite through the covalent attachment method (Lac/Fe3O4/GO). The effect of immobilization conditions on the activity and recovered activities such as contact time, the concentration of glutaraldehyde and enzyme was evaluated. The recovered activity of the immobilized laccase on the Fe3O4–graphene oxide nanocomposite was ca. 86%. Immobilized laccase unlike free laccase retained the activity and exhibited higher resistance to temperature and pH changes and also improved storage and thermal stability. Approximately 70% of relative activity for immobilized laccase was remained after being incubated for 2 h at 55 °C, but free laccase only remained 48%. Immobilized laccase retained 88% of initial activity after storage for 20 days, however, the free laccase only 32%. Finally, Lac/Fe3O4/GO capability was evaluated by the oxidation of phenol, p-chlorophenol, and 2,4-dichlorophenol. Lac/Fe3O4/GO was characterized by SEM, EDX, FT-IR, and AGFM.

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Purification and recovery of laccase produced by submerged cultures of Trametes versicolor by three-phase partitioning as a simple and highly efficient technique

Wasak A., Drozd R., Grygorcewicz B., Jankowiak D., Rakoczy R.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 4

88--95

EN

In this work, three-phase partitioning (TPP) was used for the purification of laccase from liquid cultures of Trametes versicolor. For determining the optimal conditions of TPP process, parameters such as initial pH (6.5, 7.0, 7.5, 8.0), ammonium sulphate saturation (20%-80%) and the water phase to tert-butanol ratio (1:0.5, 1:1, 1:2), were analyzed. The best conditions with 73% recovery and 24-fold purification was obtained with the use of 50% saturation with ammonium sulphate, water phase to tert-butanol ratio of 1:1 and initial pH 7.0. The molecular mass of the purified laccase secreted by analyzed strain T. versicolor was found for ≈ 66 kDa. The results showed that TPP is an efficient method for the fractionation and purification of laccase obtained from liquid cultures of T. versicolor and it allows for obtaining the relatively pure enzyme without the use of time-consuming and costly chromatographic methods.

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Microorganisms and their metabolites as potential biopreparations in wood protection

Betlej I., Andres B.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2018

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No. 104

426--431

EN

This paper presents the results of studies showing the biocidal properties of selected microorganisms: Lactobacillus brevis bacteria, yeast fungi Saccharomyces cerevisiae and fungal Aspergillus niger metabolites against white fungus Trametes versicolor . It was found that both of the studied microorganisms and the metabolites synthesized by them show properties that inhibit fungal growth on the surface of pine wood samples.

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Laccase treatment of Norway spruce wood surface improves resistance and copper fixation of treated wood

Vaukner Gabrič M., Boncina T., Humar M., Pohleven F.

Drewno : prace naukowe, doniesienia, komunikaty

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2016

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vol. 59, nr 198

19--33

EN

The effects of laccase from the white-rot basidiomycete fungus Trametes versicolor on Norway spruce wood (Pices abies) surface were studied. Experiments were performed at room temperature and at pH 4.6, without the addition of mediators. Biological, chemical and physical properties of the treated wood surface were examined by a wood decay test, a scanning electron microscopy (SEM), a Fourier transform infrared (FTIR) spectroscopy and a copper leaching test. Laccase pre-treatment of Norway spruce wood surface was shown to reduce wood decay by brown-rot fungus, Gloeophyllum trabeum and white-rot fungus, Trametes versicolor. SEM images showed expanded wood cell walls, closed pits and a more even surface after laccase treatment. FTIR analysis indicated that laccase not only catalyse depolymerisation of lignin, but also affect other wood cell wall components, such as hemicellulose and cellulose. We showed that laccase treatment altered wood properties in a way that improved wood resistance to decay and prevented leaching of copper from impregnated wood.