Author/Authors :
Mirzadeh، Shaghayegh نويسنده 1Department of Pharmaceutical Biotechnology, Faculty of Pharmacy and Biotechnology Research Center, Tehran University of Medical Sciences, Tehran 14176, IranDepartment of Environmental Health Engineering, School of Public Health; Center for Solid Was , , khezri، mostafa نويسنده , , Rezaei، Shahla نويسنده 1Department of Pharmaceutical Biotechnology, Faculty of Pharmacy and Biotechnology Research Center, Tehran University of Medical Sciences, Tehran 14176, Iran , , Forootanfar، Hamid نويسنده 1Department of Pharmaceutical Biotechnology, Faculty of Pharmacy and Biotechnology Research Center, Tehran University of Medical Sciences, Tehran , Iran,Herbal and Traditional Medicines Research Center, Kerman University of Medical Sciences, Kerman, , , Mahvi، Amir Hossein نويسنده Department of Environmental Health Engineering, School of Health; National Institute of Health Research; Center for Solid Waste Research, Institute fo , , Faramarzi، Mohammad Ali نويسنده ,
Abstract :
Background: Decolorization of hazardous synthetic dyes using laccases in both free and immobilized form has
gained attention during the last decades. The present study was designed to prepare immobilized laccase (purified
from Paraconiothyrium variabile) on porous silica beads followed by evaluation of both free and immobilized
laccases for decolorization of two synthetic dyes of Acid Blue 25 and Acid Orange 7. Effects of laccase
concentration, pH and temperature alteration, and presence of 1-hydroxybenzotriazole (HBT) as laccase mediator
on decolorization pattern were also studied. In addition, the kinetic parameters (Km and Vmax) of the free and
immobilized laccases for each synthetic dye were calculated.
Results: Immobilized laccase represented higher temperature and pH stability compare to free one. 39% and 35%
of Acid Blue 25 and Acid Orange 7 was decolorized, respectively after 65 min incubation in presence of the free
laccase. In the case of immobilized laccase decolorization percent was found to be 76% and 64% for Acid Blue 25
and Acid Orange 7, respectively at the same time. Increasing of laccase activity enhanced decolorization percent
using free and immobilized laccases. Relative decolorization of both applied dyes was increased after treatment by
laccase-HBT system. After nine cycles of decolorization by immobilized laccase, 26% and 31% of relative activity
were lost in the case of Acid Blue 25 and Acid Orange 7, respectively.
Conclusions: To sum up, the present investigation introduced the immobilized laccase of P. variabile on porous
beads as an efficient biocatalyst for decolorization of synthetic dyes.
