The invention provides olive-derived hydroxytyrosol. According to one aspect of the invention, vegetation water is collected from olives. Acid is added to stabilize the vegetation water and prevent fermentation. The mixture is incubated to allow oleoeuropein to convert to hydroxytyrosol, and then fractionated to separate hydroxytyrosol from other components. The hydroxytyrosol is useful as a natural anti-bacterial, anti-viral and fungicidal product for agricultural and pest control applications. In addition, it is useful as a therapeutic and anti-oxidant for a variety of health purposes.