Cucurbitacins

Ubiquitous in seeds is phytic acid, the hexaphosphate ester of inositol, which has been isolated from cucurbit seeds (57). Small amounts of free sugars and terpenoid glycosides (cucurbitacins) are also present (58-60), but starch is absent (1, 1). Cellulosic cell wall materials comprise the remaining carbohydrate content. 

The transformation of the lanostane keto-epoxide (72) into the cucurbitacin derivative (73) has been achieved with boron trifluoride in acetic anhydride. The presence of the acetic anhydride appears to favour the backbone rearrangement. The structure of (73) was confirmed by correlation with the oxidation product (74) of deoxybryogenin acetate. Two new cucurbitacin glycosides, arvenins 1 (75) and II (76) from Anagallis arvensis, have been reported. ... 

One may conclude from these studies that phytoalexins have a selective effect on herbivores. They inhibit feeding and growth on some, but seem to be innocuous to others. Given the coevolutionary origin of plant defenses, it is conceivable that some phytoalexins may even be kairomones for some insects. There is ample precedence to this dual role of several allelochemics (1). The example of cucurbitacins mentioned above is one of them. 

Anagalis arvensis L. Hi Lu (root) Anagalline, anagalligenone, arrenin, cucurbitacins.55 Treat snakebite, dog bite, antitoxic. 

Citrullus anguria Duch. C. edulis Spach. C. lanatus Matsumura Nakai C. vulgaris Schrad. Xi Gua (Watermelon) (fruit, seed) Cucurbitacins, carprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, sterol, citrulline.50-351 For alcohol poisoning, diabetes, nephritis, sore throat, stomatitis, demulcent. 

Cucumis melo L. Gua Di (Cantaloupe) (pedicel) Melotoxin, cucurbitacin B, cucurbitacin E, sterol33351 Produce vomiting for drug intoxication, treat toxic and chronic hepatitis and cirrhosis of the liver. 

Cucumis sativus L. Huang Gua (Cucumber) (leaf, fruit, seed) Arginine, caffeic acid, chlorogenic acid, cucurbitacins, fructose, galactose, isoquercitrin, mannose, 2,6-nonadienol, rutin, linoleic acid, oleic acid, palmitic acid, stearic acid, sterol.50351 Diuretic, purgative, vermifuge, pulp can be used for bums, scalds, and skin ailments. 

Neoalsomitra integrifoliola (Cogn.) Hutch Bang Chui Hui (stem) Cucurbitacin B, iso-cucurbitacin B, carotenoids.56 Laxative for diarrhea, treat intermittent fever, hepatitis, thyroid gland swelling. Used as a wash for contusions. 

N.A. Saponins, anagalline, tannins, cucurbitacins. Diuretic, sweat-inducing and expectorant properties. 

N.A. Cucurbita maxima L. Linoleic acid, oleic acid, cucurbitacins, vitamins.99 Against tapeworms in pregnant women and in children, treat nephritis, urinary problems. 

Finally, the triterpenoid cucurbitacin B, isolated from L. intrapetiolaris, showed activity in the KB (human oral epidermoid carcinoma) assay with EC50 value of 0.008 pg/ml. The clerodane diterpenes intrapetacin A and intrapetacin B displayed moderate activity vs KB as well [4],... 

Cucurbitacin F 95 Cowania mexicana (Rosaceae) leaves and branches EBV [26,69]... 

Alkaloids (pyrazolinc derivatives) and some others of undetermined structure have been reported from several genera. The family is known chemically for the cucurbitacins-loxic steroidal substances. In this study, 106 samples in 73 species were tested two were already known to contain alkaloids, Momordica charantia (2/11) and M. foeiida (1/2). Other positives included Coccinea addensis (1/3), Cucumis anguria, C. zeyheri, Cucurbita foelidissi-ma (2/3), Echinocystis macrocarpa, Marah macrocarpa, Melothria cordala, Momordica cissoides, M. repens (1/2), Peponium macke-nii, Trichosanthes sp. 

Pumpkin seeds contain cucurbitacins and were listed as one of the four greater cold seeds in an 18th century list of medicines. Today, pumpkin is used to treat irritable bladder and prostate complaints, namely benign prostatic hyperplasia (BPH). 

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