Bergamottin is a natural furanocoumarin found principally in grapefruit juice. It is also found in the oil of bergamot orange, from which it was first isolated and from which its name is derived. To a lesser extent, bergamottin is also present in the essential oils of other citrus fruits. Along with the chemically related compound 6',7'-dihydroxybergamottin, it is believed to be responsible for the grapefruit juice effect, in which the consumption of the juice affects the metabolism of a variety of pharmaceutical drugs. In chemical terms, bergamottin and dihydroxybergamottin are linear furanocoumarins functionalized with side-chains derived from geraniol. They are inhibitors of some isoforms of the cytochrome P450 enzyme, in particular CYP3A4. This prevents oxidative metabolism of certain drugs by the enzyme, resulting in an elevated concentration of drug in the bloodstream.
-V909.gif)