Effect Of Metal Ions On Triphenylmethane Dye Decolorization By Laccase From Trametes Versicolor

Abstract

The aim of this study was investigate the influence of different metal ions on laccase activity and triphenylmethane dye decolorization by laccase from white-rot fungus Trametes versicolor. Laccase activity was inhibited by monovalent ions (Li+, Na+, K+ and Ag+) but the presence of divalent ions increased laccase activity at the concentration of 10 mmol/l. The effect of metal ions on decolorization of triphenylmethane dyes with different structures namely Bromochlorophenol Blue, Bromophenol Blue, Bromocresol Blue and Phenol Red was tested. The presence of metal ions (Na+, K+, Mg2+, Ca2+, Ba2+, Mn2+, Zn2+) slightly decreased triphenylmethane dye decolorization by laccase from T. versicolor except Na+ and Mg2+, which caused the increase of decolorization for all tested dyes. Decolorization of selected dyes showed that the presence of low-molecular-weight compounds is necessary for effective decolorization. Hydroxybenzotriazole (HBT) is the most frequently used. Although HBT belongs to most frequently used redox mediator and generally increase decolorization efficiency, so its presence decreased decolorization percentage of Bromophenol Blue and Bromochlorophenol Blue, the influence of metal ions to dye decolorization by laccase has the similar course with or without presence of redox mediator HBT.

Laccases as Effective Tools in the Removal of Pharmaceutical Products from Aquatic Systems

“…The removal of pharmaceutically active substances by enzymes such as laccases has received considerable attention, especially in recent years. Purified laccases were first tested on organic dyes and structurally simple substrates [19][20][21][22]. The current research deals with the use of laccase for the removal of pharmaceutically important compounds belonging to drug groups, such as analgesics, antibiotics, antiepileptics, antirheumatic drugs, cytostatics, hormones, anxiolytics and sympatholytics.…”

“…The resulting by-products are generally less or non-toxic, and these processes prove effective even at very low pollutant concentrations in wastewater [17,18]. Oxidoreductases, such as laccases, stand out as predominant enzymes in these processes [19][20][21][22], owing to their versatility and an active center accommodating a broad range of substrates [23]. Laccases offer the added advantage of requiring only molecular oxygen for catalyzing reactions.…”

Decolourisation of reactive dyes with laccase-mediator system

“…Electron-donating substituents (-OH, -CH 3 , -NH 2 , -N(CH 3 ) 2 ) contribute to increased biodegradability while electron-withdrawing substituents (-COOH, -SO 3 H, -NO 2 , -Cl, -Br) resist oxidation (Suzuki et al, 2001). Chmelova and Ondrejovi confirmed the negative effect of halogen groups (-Cl, -Br) in the dye structure (Chmelova and Ondrejovic, 2015). Because of this, Magenta MB showed maximum decolourisation as the dye structure constitute electron donating substituents as shown in Figure 2(b) thus get easily oxidized by laccase.…”

Efficient dye removal by Streptomyces cyaneus lacasse heterologously expressed within S. cerevisiae cell walls immobilized within tyramine-modified alginate beads using visible light photopolymerization

“…9). The e ciency remained low due to the presence of two chloride ions per molecule, which are believed to participate in stabilizing the dye and reducing its susceptibility to degradation (Chmelová & Ondrejovič 2015). Additionally, the basic structure of methyl green is triphenylmethane (TPM), and it has been previously established that TPM-based dyes exhibit higher resistance to enzymatic degradation because laccases can oxidize the methyl carbon attached to TPM dye structure, giving stable products that are affected by p-substituted phenyl (Forootanfar et al 2012).…”