Biocatalyst laccases

Catalytic reduction of oxygen directly to water, while not as yet possible with traditional catalyst technology at neutral pH, is achieved with some biocatalysts, particularly by enzymes with multi-copper active sites such as the laccases, ceruloplasmins, ascorbate oxidase and bilirubin oxidases. The first report on the use of a biocatalyst... 

For example, the small scale of the device was intended as a demonstration of architecture suitable for implanted applications. Mano et al. demonstrated a miniature fuel cell with bilirubin oxidase at the cathode catalyst that is more active at pH 7 and tolerates higher halide concentrations than does laccase. Additionally, the long-side-chain poly-(vinylpyridine)—Os(dialkyl-bis-imidazole)3 redox polymer discussed above was employed to both lower the anode potential and, via the long side chains, enhance electron transport from the biocatalyst. The cell achieved a current density of 830 at 0.52 V... 

In the field of bioremediation, oxidoreductases are considered to be excellent biocatalysts for environmentally friendly processes. Laccases and peroxidases are widely used to treat effluents from pulp/cotton mills, food/fruit processing plants and breweries [1, 2, 37]. Laccases, peroxidases and other oxygenases are also being studied for their abihty to degrade hazardous coal substances, especially the sulfur-containing components, and in the treatment of industrial waste and contaminated soil and water in the transformation of xenobiotics, polycycHc aromatic hydrocarbons and other pollutants (biodetoxification and biodecontamination)... 

Stanescu MD, Fogorasi M, Shaskolskiy BL, Gavrilas S, Lozinsky VL (2010) New potential biocatalysts by laccase immobilization in PVA cryogel type carrier. Appl Biochem Biotechnol... 

Blue multicopper oxidases (BMCOs) such as laccase, ceruloplasmin, bilirubin oxidase (BOx), and ascorbate oxidase (AOx) have been extensively investigated as cathodic biocatalysts for DET-based biodevices [44]. BMCOs have a catalytic center consisting of four coppers a type 1 (Tl) Cu site, which accepts electrons from the substrate and from the electrode surface, and a type 2/type 3 (T2/T3) cluster, where O2 is reduced directly to water. High redox potential laccases and BOx, with redox potential up to 780 and 670 mV versus normal hydrogen electrode (NHE), respectively [44,45], can be used to create efficient biocathodes with current densities up to a few mA cm . In 2012, Shleev and coworkers used the DET ability of these enzymes to create several completely DET-based BFCs [42]. The enzymes have also been used in different MET-based approaches [46,47] specifically, Heller and coworkers... 

Biocatalysts (oxidative enzymes) this enzyme system consists of peroxidases, such as manganese peroxidase, Ugnin peroxidase and other peroxidases, phenol oxidases, such as laccases, and various low-molecular-weight agents, such as oxalate and malate. 

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