Involved in the biosynthesis of coumarins and furanocoumarins (FCs), natural products required for defense responses against attacks by predators with potential medical and agroindustrial usages such as anticoagulant, rodenticide and artificial vanilla substitutes (PubMed:29971079). Involved in linear furanocumarin (psoralen) biosynthesis (PubMed:19098286). Converts marmesin to psoralen and, with much lower affinity, 5-hydroxymarmesin to bergaptol (PubMed:19098286). (7S)-marmesin + O2 + reduced [NADPH--hemoprotein reductase] = acetone + H(+) + 2 H2O + oxidized [NADPH--hemoprotein reductase] + psoralen Optimum pH is 7.5. Secondary metabolite biosynthesis. Accumulates in roots after wounding. Psoralen possesses photocarcinogen properties. It intercalates in double-stranded DNA and cross-links pyrimidine bases under UV-A irradiation. Psoralen is widely used in combination with UV-A radiation to treat a variety of skin disorders like psoriasis or eczema. Belongs to the cytochrome P450 family.