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Published on: March 6, 2019
The influence of hydroquinone on tyrosinase kinetics
Michael R L Stratford1, Christopher A Ramsden, Patrick A Riley
1Gray Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Roosevelt Drive, Oxford OX3 7DQ, UK.
Abstract:
In vitro studies, using combined spectrophotometry and oximetry together with hplc/ms examination of the products of tyrosinase action demonstrate that hydroquinone is not a primary substrate for the enzyme but is vicariously oxidised by a redox exchange mechanism in the presence of either catechol, L-3,4-dihydroxyphenylalanine or 4-ethylphenol. Secondary addition products formed in the presence of hydroquinone are shown to stimulate, rather than inhibit, the kinetics of substrate oxidation.
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