Using the tyrosinase from Agaricus Bisporus and the cyanide hydratase from Aspergillus Niger K10 in the degradation of phenol and o-, m-, and p-cresol and the free cyanide from coke plant wastewater
Abstrakt
Coke plant wastewater contains primarily phenolics and tars. The most abundant of them are phenol (cca 56 %), cresols (cca 30 %) and xylenols (4 %), but also a variable amount of free and bound cyanides are present.
Compared to chemo - physical methods of wastewater dephenolization, the use of oxidative enzymes of plant and microbial origin is a much cheaper alternative. For this application, the use of oxidoreductases such as peroxidase, laccase or tyrosinase is promising1.
Tyrosinase (polyphenol oxidase, EC 1.14.18.1) catalyzes the hydroxylation of monophenols to o-hydroquinones (catechols) and their subsequent dehydrogenation to quinones, which are then non-enzymatically polymerized, forming insoluble brown pigments4. Tyrosinase is easily available as a crude extract from the fruiting bodies of the common mushroom (Agaricus bisporus).
In this work we have exploited the catalytic properties of tyrosinase in combination with cyanide hydratase (CHT) for the degradation of phenols and cresols from coke plant wastewater.