Umbelliferones (7-hydroxycoumarins) [ref 9] are substances present in many species of plants, especially umbelliferae, fabaceae, and oleaceae, which include such common plants as manna ash, sweet woodruff, German chamomile, celery, parsley, and others. In nature, umbelliferones help protect plants from cellular damage, infestation, trauma, and infection. Their 7-hydroxycoumarin derivatives (4-methylumbelliferones) [ref 10] are used in liver therapy, as reagents, plant growth factors, sunscreens, choleretics, and spasmolytics. They are also used as light-protective agents, in the calibration of medical lasers, and in analytical chemistry for the quantitation of nitric acid.