Highly-stable Madurella mycetomatis laccase immobilized in silica-coated ZIF-8 nanocomposites for environmentally friendly cotton bleaching process

Tulek A., YILDIRIM D., Aydin D., Binay B.

COLLOIDS AND SURFACES B-BIOINTERFACES, cilt.202, 2021 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 202
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1016/j.colsurfb.2021.111672
  • Dergi Adı: COLLOIDS AND SURFACES B-BIOINTERFACES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Biotechnology Research Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, EMBASE, INSPEC, MEDLINE, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Madurella mycetomatis laccase, Metal-organic frameworks, Immobilized enzyme, Cotton bleaching, ZEOLITIC IMIDAZOLATE FRAMEWORKS, METAL-ORGANIC FRAMEWORK, BIODEGRADATION, REMOVAL, ENCAPSULATION, DEGRADATION, STABILITY, COMPOSITE, OXIDATION, MEMBRANE
  • Çukurova Üniversitesi Adresli: Evet

Özet

In this study, a laccase from Madurella mycetomatis (MmLac) was produced heterologously in Pichia pastoris; the initial immobilization in a metal-organic framework (MOF) (MmLac/ZIF-8) was achieved using zinc nitrate and 2-methylimidazole. Due to the instability of MmLac/ZIF-8 in an acidic medium, a silica layer was created on the surface of MmLac/MOF-8. The immobilized laccase composite (silica@MmLac/ZIF-8) obtained was further treated with glutaraldehyde (silica@Glu-MmLac/ZIF-8) to increase stability of composite. Fourier-transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy techniques were used to confirm the immobilization of MmLac and to investigate the morphology of the immobilized laccase samples. The MmLac samples were also characterised in terms of optimum pH, temperature and thermal stability. The optimum pH of all the MmLac samples was determined to be 4.0. The free MmLac showed maximum activity at 55 degrees C, whereas both silica@MmLac/ZIF-8 and silica@Glu-MmLac/ZIF-8 were maximumly active at 65 degrees C. The silica@MmLac/ZIF-8 and silica@Glu-MmLac/ZIF-8 were 9.3- and 11.8-fold higher in stability, respectively, than the free MmLac at 65 degrees C. Furthermore, both silica@MmLac/ZIF-8 and silica@Glu-MmLac/ZIF-8 showed a higher bleaching performance than free MmLac on cotton woven fabric. According to these results, silica@MmLac/ZIF-8 and silica@Glu-MmLac/ZIF-8 may be promising candidates for biocatalysts in laccase-based biotechnological applications.