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| Section2 = }} Ginkgotoxin (4'-O-methylpyridoxine) is a neurotoxin naturally occurring in ''Ginkgo biloba''. It is an antivitamin structurally related to vitamin B6 (pyridoxine). It has the capacity to induce epileptic seizures. == Occurrence == Seeds and phytopharmaceuticals derived from the plant ''Ginkgo biloba'' are dietary supplements used to improve memory, brain metabolism, and blood flow, and to treat neuronal disorders. It has been long used for a wide range of medicinal purposes. For instance, in Japan and China, ''Ginkgo biloba'' is used to treat cough, bronchial asthma, irritable bladder and alcohol abuse. Ginkgotoxin is found in the seeds and, in lesser amounts, in the leaves of ''Gingko biloba''. The seeds can be consumed as is and the leaves can be used to prepare the dietary supplements. Analyses of raw seeds from eight different location in Japan by high-performance liquid chromatography showed concentrations of ginkgotoxin varying from 0.173 to 0.4 mg/g of seeds. Also, there is a seasonal variation of ginkgotoxin concentration in the seeds. The maximum has been observed in August. Analyses of the powder of ''Ginkgo biloba'' capsules revealed the presence of ginkgotoxin. However, as the leaves contain very small amounts that are not of toxicological relevance, it shouldn't pose any threat to the consumers. Ginkgotoxin-5'-glucoside is a derivative of ginkgotoxin that possesses a glycosyl in the 5' position. Its content is higher than the concentration of ginkgotoxin in heated seeds (boiled or roasted). Liberation of ginkgotoxin by enzymatic hydrolysis of the glycosidic linkage is possible. Nevertheless, the toxicity of the mechanism of action glucoside form is not fully understood. Ginkgotoxin can also be found in other plants of the genus ''Albizia''.〔 However, these plants have no known dietary use for humans, so their production of ginkgotoxin is of lesser concern. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ginkgotoxin」の詳細全文を読む スポンサード リンク
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