In this ORAC test, they looked at a home prepared version of extra version olive oil infused with parsley. We can conclude over half of the antioxidants in it are coming from the parsley since the value of plain extra virgin olive oil is roughly 50% lower.
ORAC Source
USDA Database for the Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods, Release 2 - Prepared by Nutrient Data Laboratory, Beltsville Human Nutrition Research Center (BHNRC), Agricultural Research Service (ARS), U.S. Department of Agriculture (USDA) - May 2010