Preparation of cross-linked tyrosinase aggregates

Date

2008-02-01

Author

Aytar, Burcu Selin
Bakir, Ufuk

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Tyrosinase from mushroom was immobilized as a cross-linked enzyme aggregate (CLEA) via precipitation with ammonium sulfate and cross-linking with glutaraldehyde. The effects of precipitation and cross-linking on CLEA activity were investigated and the immobilized tyrosinase was characterized. Sixty percent ammonium sulfate saturation and 2% glutaraldehyde were used; a 3-h cross-linking reaction at room temperature, at pH 7.0 was performed; particle sizes of the aggregates were reduced; consequently, 100% activity recovery was achieved in CLEAs with enhanced thermal and storage stabilities. Slight changes in optimum pH and temperature values of the enzyme were recorded after immobilization. Although immobilization did not affect V-max, substrate affinity of the enzyme increased. Highly stable CLEAs were also prepared from crude mushroom tyrosinase with 100% activity recovery.

Subject Keywords

Applied Microbiology and Biotechnology, Biochemistry, Bioengineering

URI

https://hdl.handle.net/11511/65002

Journal

PROCESS BIOCHEMISTRY

DOI

https://doi.org/10.1016/j.procbio.2007.11.001

Collections

Department of Chemical Engineering, Article

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Citation Formats

B. S. Aytar and U. Bakir, “Preparation of cross-linked tyrosinase aggregates,” PROCESS BIOCHEMISTRY, pp. 125–131, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65002.