Amentoflavone

Amentoflavone is a biflavonoid (bis-apigenin coupled at 8 and 3' positions, or 3′,8′′-biapigenin) constituent of a number of plants including Ginkgo biloba, Chamaecyparis obtusa (hinoki), Hypericum perforatum (St. John’s Wort) and Xerophyta plicata.

Amentoflavone can interact with many medications by being a potent inhibitor of CYP3A4 and CYP2C9, which are enzymes responsible for the metabolism of some drugs in the body. It is also an inhibitor of human cathepsin B.

Amentoflavone has a variety of in vitro activities including antimalarial activity, anticancer activity (which may, at least in part, be mediated by its inhibition of fatty acid synthase), and antagonist activity at the κ-opioid receptor (K_e = 490 nM) as well as activity at the allosteric benzodiazepine site of the GABA_A receptor as a negative allosteric modulator.