(+)-nootkatone, a bicyclic conjugated sesquiterpene ketone with a grapefruit-like flavor, is commonly used in fragrance, food, cosmetics and pharmaceutical industry. It can be synthesized from (+)-valencene via biotransformation. (+)-nootkatone is the active ingredient responsible for the antiplatelet effect of Cyperus rotundus, a well-known oriental traditional medicine. It also shows promising efficacy against Staphylococcus aureus biofilms.