Synthesis of cross-linked protein-metal hybrid nanoflowers and its application in repeated batch decolorization of synthetic dyes

• Published in: Journal of hazardous materials Vol. 347; pp. 442 - 450
• Main Authors: Patel, Sanjay K.S., Otari, Sachin V., Li, Jinglin, Kim, Dong Rip, Kim, Sun Chang, Cho, Byung-Kwan, Kalia, Vipin C., Kang, Yun Chan, Lee, Jung-Kul
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 05.04.2018
• Subjects: Cross-linking; Immobilization; Laccase; Protein-inorganic hybrid; Synthetic dyes; Protein-inorganic hybrid; Immobilization; Synthetic dyes; Cross-linking; Laccase
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2018.01.003

•Cross-linked (CL) laccase-metal hybrid nanoflower (NF) was prepared.•The catalytic efficiency of CL-NF laccase was 2.2-fold higher than that of free laccase.•CL-NF laccase showed 2.6-fold higher oxidation potential than free laccase towards phenolic compounds.•Under repeated batch conditions, it retained high decolorization efficiency for synthetic dyes. Herein, we report the preparation of a cross-linked protein-metal hybrid nanoflower (NF) system for laccase immobilization. The immobilized laccase showed effective encapsulation yield and activity recovery of 78.1% and 204%, respectively. The catalytic efficiency (kcatVmax−1) of cross-linked NF (CL-NF) was 2.2-fold more than that of free laccase. The CL-NF also exhibited significantly higher stability towards pH and temperature changes. It exhibited excellent storage stability and tolerance towards solvents and inhibitors as compared with the free enzyme. After 10 cycles of reuses, the NF and CL-NF laccase showed 41.2% and 92.3% residual activity, respectively. The CL-NF showed high oxidation potential, 265% that of the free enzyme, towards phenolic compounds. The CL-NF laccase retained the residual decolorization efficiency of up to 84.6% for synthetic dyes under repeated batch conditions of 10 cycles. These results suggested that the preparation of CL-NF is an effective approach to enhance the enzymatic properties and has great potential in many industrial applications.