Methoxsalen is a naturally occurring photoactive chemical found in the seeds of the Ammi majus (Umbelliferae) plant and in the roots of Heracleum candicans. It belongs to a group of compounds known as psoralens or furocoumarins. https://medium.com/@herbl3926/natberb-100-natural-berberine-extract-supplier-manufacturer-05e02be55b04