Immobilization of laccase in kappa-carrageenan based semi-interpenetrating polymer networks

Makas, Y. Gizem
Hasırcı, Nesrin
Laccase enzyme (L) was immobilized by entrapment into semi-interpenetrating polymer networks (semi-IPNs) prepared from kappa-carrageenan with either poly(acrylamide-acrylic acid) [P(AAm-AA)/kappa-car] or poly(acrylamide-itaconic acid) [P(AAm-IA)/kappa-car]. For both systems, immobilized enzymes achieved the same optimum values observed for free enzyme (pH = 5.0 and T = 40 degrees C), except for P(AAm-IA)/kappa-car system there was a shift to 5.5 in optimum pH value. At the end of 42 days of storage immobilized enzymes retained more than 80% of their original activities while the retained activities of both systems after 10 uses in batch type application were found to be higher than 50%. K-m values were calculated as 2.52 x 10(-2) mM and 1.08 x 10(-2) mM and V-max values were found as 6.8 x 10(-3) mM min(-1) and 4.4 x 10(-3) mM min(-1), for P(AAm-AA)/kappa-car-L and P(AAm-IA)/kappa-car-L, respectively. When methyl orange containing solutions (10 mg/L) were treated with the immobilized laccases (68.2 U), enzymatic decolorization of methyl orange in 6 h was achieved to the level of 35% for both systems. Supplementing the reaction medium with ABTS as the redox mediator increased this value to about 70%. These initial results show that, laccase containing semi-IPNs can find some applications in decolorization of the industrial wastes.


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Çırpan, Ali; Toppare, Levent Kamil; YAGCI, Y (Informa UK Limited, 2003-01-01)
Cholesterol oxidase has been immobilized in conducting copolymers of thiophene-3-yl acetic acid cholesteryl ester with pyrrole (CM/PPy) and polypyrrole (PPy) via electropolymerization. p-Toluene sulphonic acid was used as the supporting electrolyte. Kinetic parameters (V-max and K-m) and operational stability of enzyme electrodes were investigated. Surface morphology of the films was examined by scanning electron microscope.
DEMIRCIOGLU, H; BEYENAL, H; TANYOLAC, A; Hasırcı, Nesrin (1994-12-01)
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Polyacrylamide-based semi-interpenetrating networks for entrapment of laccase and their use in azo dye decolorization
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In this study, laccase from Trametes versicolor was immobilized in poly(acrylamide-crotonic acid)/sodium alginate [P(AAm-CrA)/alginate], poly(acrylamide-crotonic acid)/K-carrageenan [(P(AAm-CrA)/K-car)], poly(acrylamide-citraconic acid)/sodium alginate (P(AAm-CA)/alginate), and poly(acrylamide-citraconic acid)/K-carrageenan (P(AAm-CA)/K-car) semi-interpenetrating network by entrapment method. Optimum pH and temperatures values were determined between 5.0-6.0 and 40-50 degrees C for free laccase (FL) and imm...
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Citation Formats
Y. G. Makas, N. KALKAN, S. AKSOY, H. ALTINOK, and N. Hasırcı, “Immobilization of laccase in kappa-carrageenan based semi-interpenetrating polymer networks,” JOURNAL OF BIOTECHNOLOGY, pp. 216–220, 2010, Accessed: 00, 2020. [Online]. Available: