Synthesis of the antioxidant hydroxytyrosol using tyrosinase as biocatalyst

Hydroxytyrosol (HTyr), a natural ortho-diphenolic antioxidant with health-b eneficial properties that mainly occurs in virgin olive oil and olive oil m ill waste waters (also known as vegetative waters), has been enzymatically synthesized using mushroom tyrosinase. This o-diphenol (not commercially av ailable) was obtained from its monophenolic precursor tyrosol (commercially available) in the presence of both tyrosinase and ascorbic acid. The react ion synthesis is continuous, easy to perform, and adaptable to a bioreactor for industrial purposes. The HTyr concentration is time-predicted, and the yield of reaction can be 100%. The synthesis method reported here is an al ternative approach to obtain this compound in an environmentally friendly w ay.