Peroxidase Oxidation of Phenols

Horseradish Peroxidase Immobilized into Organogel-Silica Composite for Transformation of Chlorophenols to Biodegradable Organic Acids

“…At all concentrations, free HRP has nearly five times higher activity as compared to immobilized HRP in organogel-silica hardened material. These findings are comparable with literature for immobilized enzymes and is due to diffusion limitations of substrate for immobilized enzymes [20] Optimization of different parameters for oxidation of chlorophenols It is well-known that Horseradish peroxidase catalyzes H 2 O 2 -mediated oxidation of substrates with different functional attribution, including phenols [22] where it is customary to observe decrease in chlorophenol concentration while studying the oxidative removal/degradation of chlorophenols. We used liquid chromatography to determine phenol concentrations in aqueous solutions before and after enzymatic oxidation.…”

Economic comparison of enzymatic reactors and advanced oxidation processes applied to the degradation of phenol as a model compound

“…Conventional methods of wastewater treatment based on activated sludge are in some cases not effective at reducing toxic pollutants (Wilberg et al 2002), and thus post-treatment methods for removal of these compounds are being investigated: i) physical methods such as adsorption (Khan et al 1997;Viraraghavan & Alfaro 1998) or membrane separation (Cahn & Li 1974); ii) chemical treatments, such as those based on oxidative catalysis (Gianfreda et al 2006), electro-oxidation (Bubnov et al 2004), Fenton reaction (Kang et al 2002), ozonation and other advanced oxidation processes (AOPs) (Wu et al 2001;Esplugas et al 2002); iii) microbial degradation with bacteria (Erhan et al 2002), yeast (Adav et al 2007) and fungi (Ryan et al 2007); and iv) enzymatic treatment, based on peroxidases (Flock et al 1999;Wilberg et al 2002;Bassi et al 2004;Davidenko et al 2004;Carvalho et al 2006;Gianfreda et al 2006).…”

“…Many authors have been working on improved technical and operational parameters affecting phenol degradation with peroxidases. The mechanism of phenol degradation involves the formation of low-molecular-weight products or polymer products insoluble in water (Sakurai et al 2003;Davidenko et al 2004). Dec and coworkers (Dec et al 2001) demonstrated that peroxidases catalyze not only the oxidation of several substituted phenols but also their decarboxylation and demethoxylation.…”

Removal of α-naphthol and other phenolic compounds from polluted water by white radish (Raphanus sativus) peroxidase in the presence of an additive, polyethylene glycol

“…These processes suffer from limitations like formation of hazardous by-products, incompleteness of purification, high costs, low efficiency, and applicability to limited concentration range [11].…”