Phenolic compounds are priority pollutants with high toxicity even at low concentrations. Ever increasing burden of pollutants in major rivers and other water bodies along with stringent environmental legislation and focus on adaptation to eco-friendly treatment approaches have necessitated the need for the removal of these phenolics before being discharged to rivers and other fresh water-bodies. Compared to physicochemical treatment, enzymatic treatment has proven to be the best way to treat various phenolic compounds under mild conditions with different enzymes such as peroxidases, laccases, and tyrosinases. In present study, we have designed a simple and efficient method for removal of phenols from effluent wastewater using an immobilized preparation of Mushroom tyrosinase. The enzyme was isolated from Agaricus bisporus (Button mushroom) and partially purified and subsequently various immobilization matrices were evaluated for their efficiency of immobilization, reproducibility, rate of degradation of phenolics, stability and reusability. Experiments showed that the in situ polymerisation of acrylamide monomer along with the enzyme gave most effective entrapment with high reproducibility amongst the tested methods. Immobilized tyrosinase was much more stable than the free tyrosinase in storage and that the immobilized tyrosinase could even retain about most of its original activity after repeated use 10 times in a batch system. This method could provide and an economical and stabilized immobilized-enzyme method for the removal of phenol in wastewater.
Key words: Phenolics, Mushroom Tyrosinase, Immobilization, Polyacrylamide gel immobilization
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