Immobilization of laccase from Trametes versicolor on Lifetech (TM) supports for applications in degradation of industrial dyes

Abstract

In this study, immobilization of laccase from Trametes versicolor on eight Lifetech (TM) supports, with different characteristics (pore size, length of the spacer arm and functional groups), was studied and optimized for intended use in bioremediation for decolorization of industrial wastewaters. Out of six tested amino-functionalized supports, the most promising carrier was proved to be porous Lifetech (TM) ECR8309F with primary amino groups and a C2 spacer arm. Onto this support, laccase is attached by forming electrostatic interactions so that the most active preparation has shown the activity of 66876 U/g support. On the other hand, during immobilization of laccase on epoxy-functionalized Lifetech (TM) ECR8285F, via hydrophobic interactions and covalent bonding confirmed by a desorption assay, immobilization yield of 60 % and the activity of 118929 U/g were accomplished. Furthermore, immobilized enzyme on this support showed high capacity for decolorization of dyes (Lanaset (R) Violet B, Lanaset (R) Blue 2R, bromothymol blue and bromocresol green), by combination of both adsorption and enzyme degradation. Decolorization was in the range of 88 to 96 % after 4 h, with more than 80 % achieved after only 45 min. Also, this preparation demonstrated high operational stability during seven consecutive reuses in all examined dye reaction systems.

U ovom radu je ispitivana i optimizovana imobilizacija lakaze producenta Trametes versicolor na osam Lifetech™nosača, različitih karakteristika (kao što su veličina pora, dužina “nožice” i funkcionalne grupe), za predviđenu namenu u bioremedijaciji radi obezbojavanja industrijskih otpadnih voda. Od šest ispitanih amino-funkcionalizovanih nosača, kao najadekvatniji se pokazao porozni Lifetech™ ECR8309F nosač sa primarnim amino grupama i C2 “nožicom”. Na ovaj nosač lakaza se vezuje formiranjem elektrostatičkih interakcija i dobijeni preparat je imao aktivnost od 66876 U/g nosača. Nasuprot tome, prilikom imobilizacije lakaze na epoksi/butil metakrilatni nosač Lifetech™ ECR8285F, hidrofobnim interakcijama i kovalentnim vezama, što je potvrđeno tretmanom imobilisanog preparata desorpcionim sredstvima, postignut je prinos imobilizacije proteina od 60 %, a dobijena je aktivnost od 118929 U/g. Pored toga, preparat ECR8285F-lakaza pokazao je veliku aktivnost u obezbojavanju boja (Lanaset® Violet B, Lanaset® Blue 2R, bromtimol plavo i bromkrezol zeleno) kombinacijom adsorpcije i enzimske razgradnje, u opsegu obezbojavanja od 88 % do 96 % nakon 4 h, sa više od 80 % obezbojavanja postignutog nakon samo 45 min. Takođe, ovaj preparat je pokazao veliku operativnu stabilnost tokom 7 uzastopnih ponovnih upotreba u svim ispitanim reakcionim sistemima.