Chem. Pharm. Bull. 55(1) 133—136 (2007)

Cucumis sativus L., which belongs to the Cucurbitaceae family, is cultivated worldwide as a vegetable crop. The fruit of C. sativus (cucumber) is used not only as food, but also in folk medicines and folk cosmetics. The leaves, stems and roots of C. sativus are reportedly used in Chinese folk medicine as antidiarrheal, detoxicant and antigonorrheal agents. However, these are not major uses, so after harvest of the cucumber fruits, almost all the remaining plant material is waste. There have been few chemical studies regarding the constituents of this material. The only reports are by Enslin et al., who isolated the triterpenoid cucurbitacin C, and McNally et al., who isolated C-glycosyl flavonoid. Thus, in the present study, we attempted to identify useful components of cucumber plant material to support its development as a medicinal resource. As part of our ongoing search for medicinal materials in cucumber plant material, chromatographic separation and purification led to the identification of two new megastigmanes, one known megastigmane, one known carotenoid, one known lignan and three other known compounds. In the present paper, we report the isolation and structural elucidation of the new megastigmanes.