Hematin and CuII control generations of hydroperoxyl and superoxide radicals to activate galactose oxidase for 5-hydroxymethylfurfural conversion

Yao Chen; Jinxin Zou; Peijun Ji; Wei Feng

doi:10.1016/j.isci.2023.108452

Hematin and Cu^II control generations of hydroperoxyl and superoxide radicals to activate galactose oxidase for 5-hydroxymethylfurfural conversion

iScience. 2023 Nov 17;26(12):108452. doi: 10.1016/j.isci.2023.108452. eCollection 2023 Dec 15.

Authors

Yao Chen¹, Jinxin Zou¹, Peijun Ji², Wei Feng¹

Affiliations

¹ Department of Biological Engineering, Beijing University of Chemical Technology, Beijing, China.
² Department of Chemical Engineering, Beijing University of Chemical Technology, Beijing, China.

Abstract

We present a significant finding that Cu(II) ions can activate hematin (Hem) to generate more HOO⋅ and O₂^⋅- radicals from the decomposition of H₂O₂. Galactose oxidase (GO) and hematin have been simultaneously immobilized by coordinating to Cu(II) ions (GO&Hem@Cu(II)). The radicals HOO⋅ and O₂^⋅- and dioxygen O₂ can be in situ generated from the byproduct H₂O₂ by the Cu(II)-activated hematin. Ample experimental evidence supports the discovery that the immobilized GO is reactivated by the in situ generated HOO⋅ and O₂^⋅-. For the conversion of 100 mM 5-hydroxymethylfurfural (HMF) in water, GO&Hem@Cu(II) (0.8 mg/mL GO encapsulated) has achieved a 99.5% conversion within 180 min. In contrast, 0.8 mg/mL free GO M_3-5 variant (ACS Catalysis 2018, 8, 4025) has achieved an HMF conversion of 17.3%. For the conversion of HMF (1,000 mM) by GO&Hem@Cu(II) (4 mg/mL GO encapsulated), the HMF conversion is 98.8% after 8 h reaction.

Keywords: Biomass; Chemical engineering; Chemistry.