Quantitative determination of furocoumarins in samples of "Carapia" by capillary gas chromatography

The occurrence of furocoumarins in the Moraceae has already been demonstrat ed. We present here the results concerning the chemical composition and qua ntification of furocoumarins from "carapia" (Dorstenia species, Moraceae) e mployed in Brazil because of its medicinal properties against skin diseases . A capillary gas chromatographic procedure is described for the simultaneo us determination of the furocoumarins (psoralen, bergapten, pimpinellin, an d isopimpinellin) in rhizomes and aerial parts of Dorstenia tubicina, Dorst enia asaroides and Dorstenia vitifolia and in commercial samples. The metho d is shown to be sensitive and reproducible, and may have application in th e analysis of "carapia" crude drugs.