Zinc’s impact on the growth and laccase activity of Trametes pubescens and an equilibrium study of zinc adsorption

ABSTRACT

Due to the influence of some ions on laccase production by Trametes pubescens, the impact of different concentrations of zinc (Zn) on fungus growth and laccase production was investigated. The removal kinetics and adsorption isotherm of Zn by T. pubescens from an aqueous solution were evaluated. The results demonstrated the growth inhibition of fungus by an increase in Zn concentration. Zn concentrations of 10 and 20 mg L⁻¹ in the medium caused an increase in the growth of fungus. Laccase production reduced at 100 and 200 mg L⁻¹ of Zn. The kinetic parameters of Zn adsorption onto the biomass of fungus from aqueous solutions (containing 200 mg L⁻¹ Zn) obtained by experiments at different contact times. The results indicated a trend of increasing Zn removal by fungus with the contact time, and it was well-described by the Intra-particle diffusion and Elovich models. The maximum removal of Zn was 67.1% at 7200 min, with a maximum sorption capacity of 44.7 mg g⁻¹. The adsorption of Zn was well-fitted to the Freundlich and Langmuir sorption models. This study indicated an impact of a low concentration of Zn to increase laccase production and the feasibility of this fungus to remove Zn from aqueous solutions.

KEYWORDS:

• Adsorption isotherm
• Trametes pubescens
• kinetic of removal
• Laccase activity
• Zinc

Acknowledgements

The authors would like to thank the Research council of Shahid Chamran University of Ahvaz for the support of this study (GN. SCU. AS1401.248).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Azadeh Farhadi

Azadeh Farhadi is a Ph.D. student of soil biology and biotechnology.

Naeimeh Enayatizamir

Naeimeh Enayatizamir, an associate professor of soil biology and biotechnology, searches on both plant growth promoting bacteria and bioremediation and Biodegradation of recalcitrant compounds.

Neda Moradi

Neda Moradi, an assistant professor of soil chemistry and pollution, writes on metals pollution in soil and Soil amendments.

Mehdi Taghavi

Mehdi Taghavi, an assistant professor of chemistry, writes on material characterization, plymer and nanomaterials.