Citrullus colocynthis (L.) Schrad. - Cucurbitaceae - colocynth, bitter apple, Koloquinte, Purgiergurke

Perennial herb, native to the Mediterranean, North africa and Asia, naturalized in Australia; stem vine-like; leaves palmately lobed (3-7); flowers solitary, yellow; fruit spheric, 5-10cm in diameter, yellow-green to marble, pulp with extremely bitter taste.
„In pre-modern medicine it was an ingredient in the electuary called confectio hamech, or diacatholicon, and most other laxative pills; and in such cases as required purging, it was very successful. It is one of the most violent purgative drugs known; insomuch that it excoriates the passages to such a degree as to sometimes draw blood and induce a so-called „superpurgation“.“ http://en.wikipedia.org/wiki/Citrullus_colocynthis

„The chemical constituents of Citrullus colocynthis (L.) Schrad. have been found to consist mainly of glycosides which upon enzymatic hydrolysis yield elaterin (cucurbitacin E), elatericin B (cucurbitacin I) and dihydroelatericin B (cucurbitacin L).“
[Constituents of Citrullus colocynthis (L.) Schrad., Lavie, D., Willner, D., Merenlender, Z., Phytochemistry, 3(1), 1964, 51-56]

„A qualitative and quantitative study of the glycosidal content of the different organs and parts of Citrullus colocyntbis Schrad. were undertaken. Qualitative study revealed the presence af α-elaterin 2–D–glucopyranoside and its aglycone in all organs; cucurbitacin B, I, and L (both free and glycosidal forms) in stems, leaves, and fruits. A suggested procedure for the estimation of α-elaterin glycoside was also given. The highest percentage of the glycoside (0.22) was found in the pulp of the fruits and the lowest percentage in the roots (0.049). The seeds, stems, leaves and rind contain 0.18,0.17, 0.15, and 0.08 percent respectively.“
[The glycosidal content of the different organs of Citrullus colocynthis., Darwish–Sayed, M., Balbaa, S. I., Afifi, M. S., Planta medica, Vol.26(07), 1974, 293-298]