What toxin found in ginkgo seeds is also called 4'-O-methylpyridoxine?

What toxin found in ginkgo seeds is also called 4'-O-methylpyridoxine? The answer is ginkgotoxin.

Ginkgotoxin is the common name for 4'-O-methylpyridoxine, a neurotoxic compound found naturally in Ginkgo biloba. It is structurally related to vitamin B6 and acts as an antivitamin: rather than supplying normal vitamin B6 activity, it can interfere with processes that depend on it.

The toxin occurs most notably in ginkgo seeds, although smaller amounts have been found in leaves. Reported concentrations in raw seeds vary with location and season, with some Japanese samples measuring roughly 0.173 to 0.4 milligrams per gram. The highest seed concentrations have been observed in August.

Large amounts of ginkgo seeds, particularly when eaten by children, can cause loss of consciousness, convulsions, and potentially death. Ginkgotoxin is believed to reduce pyridoxal kinase activity, lowering the availability of active vitamin B6 for neurotransmitter production. That mechanism helps explain its association with seizures. Cytisine, taxine, and ricin are distinct plant toxins, not alternate names for this compound.