• Webster's Revised Unabridged Dictionary
    • n Umbelliferone (Chem) A tasteless white crystalline substance, C9H6O3, found in the bark of a certain plant (Daphne Mezereum), and also obtained by the distillation of certain gums from the Umbellifer√¶, as galbanum, asafetida, etc. It is analogous to coumarin. Called also hydroxy-coumarin. Its strong fluorescence under ultraviolet light makes it useful in analytical biochemistry, as, for exmple, to detect phosphatase activity by hydrolysis of umbelliferyl phosphate.
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Century Dictionary and Cyclopedia
    • n umbelliferone A colorless compound of resins from umbelliferous plants, particularly of asafetida resin, and also by the action of sulphuric acid on a mixture of resorcinol and malic acid. It crystallizes in slender needles and melts at 223–224° C.
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