Scopoletin is a coumarin found in the root of plants in the genus Scopolia such as Scopolia carniolica and Scopolia japonica, in chicory, in Artemisia scoparia, in the roots and leaves of stinging nettle, in the passion flower, in Brunfelsia, in Viburnum prunifolium, in Solanum nigrum, in Datura metel, in Mallotus resinosus, and in Kleinhovia hospita. It can also be found in fenugreek, vinegar, some whiskies and in dandelion coffee. A similar coumarin is scoparone. Scopoletin is highly fluorescent when dissolved in DMSO or water and is regularly used as a fluorimetric assay for the detection of hydrogen peroxide in conjunction with horseradish peroxidase. When oxidized, its fluorescence is strongly suppressed.