Bergamottin
Bergamottin, also called 5-geranoxypsoralen, is a natural chemical found mainly in the pulp of grapefruits and pomelos, and in the peel and pulp of bergamot oranges. It is a type of furanocoumarin with a side chain derived from geraniol.
What it does
Bergamottin can inhibit certain enzymes in the body that metabolize drugs, especially CYP3A4. When these enzymes are blocked, some medicines are not broken down as quickly, which can raise their levels in the blood. This is why grapefruit and its juice can cause interactions with many drugs.
Why it matters
While grapefruit interactions are often viewed as unwanted, inhibiting CYP3A4 can, in theory, boost the oral availability of some drugs. Researchers are exploring whether Bergamottin and related compounds could be used to improve drug delivery. For example, another strong CYP3A4 inhibitor, ritonavir, is used with some HIV medicines to enhance their levels.
Biosynthesis (how the body makes Bergamottin)
Bergamottin comes from the shikimate pathway. The process starts with umbelliferone and uses DMAPP to build up a chain of steps:
- Form demethylsuberosin, then cyclize to marmesin
- Oxidize and modify to psoralen, then add a hydroxyl to form bergaptol
- Methylate bergaptol to bergapten
- Finally attach a geranyl group (geranyl pyrophosphate) to bergapten to form bergamottin
Related compounds
Dihydroxybergamottin is a close relative and shares similar effects on drug metabolism.
This page was last edited on 2 February 2026, at 03:16 (CET).