Cucurbitaceae, bitter taste

Cucurbitacin is a bitter-tasting principle that can be isolated from members of the family Cucurbitaceae, such as cucumber Cucumis sativus) and melon (Cucumis melo L.). In particular, cucurbitacin149 and momordicine,150 which have an intensely bitter taste, are contained abundantly in Momordica charantia (bitter melon in English, go-yaa in Okinawa, Japan), which people enjoy due to its bitterness. There are more than 18 kinds of cucurbitacin, and among them cucurbitacin B is a typical component. It has been reported that cucurbitacin exhibits anticancer activity.1 1 In addition, it is used for the treatment of hepatic disease in traditional Chinese medicine. It is also found in some herbal teas. 

The name of about 50 naturally abundant cucurbitanes stems from Cucurbitaceae, the Latin term of cucurbitaceous plants such as cucumbers and pumpkins, known since antiquity for their beneficial and toxic properties. One of the most frequently isolated representatives is the bitter substance (+)-cucurbitacin B from Phormium tenax and Ecballium elaterium (Cucurbitaceae), also found in Iberis species (Cru-ciferae), Euphorbiaceae and Scrophulariaceae. (+)-Cucurbitacin F from Cucumis angolensis and C. dinteri is reported to inhibit the growth of human tumor cells. Toxic cucurbitacines shape the unpleasant bitter taste of salads prepared from spoiled cucumbers Cucumis sativus some representatives are reported to be antihypertonic, antirheumatic, and also active against HIV. 

Hopanoids are membrane stabilizers in certain procaryotes (E 2.2). Their hydrophilic, polyhydroxylated side-chain is directed towards the aqueous face the lipophilic ring system is integrated in the lipophilic core of the membranes. Lanosterol is used as emulsifier in the pharmaceutical industry. Cucurbitacins due to their bitter taste may discourage animal predators, but attract certain beetles, which use Cucurbitaceae as food plants (E 5.5.3). 

Vegetables of the cucurbit family (Cucurbitaceae), which includes squashes, melons, pumpkins, cucumbers and gourds of the genera Benincasa, Citrullus, Cucumic, Cucurbita, Lagemria and Lujfa, occasionally show bitter taste in response to various... 

A special group of cucurbitacins are found in bitter melon, also known as bitter gourd or bitter squash Momordica charantia, Cucurbitaceae), which belongs to the most bitter of the edible fruits. The bitter taste of bitter melon is caused by a number of cucurbitane-type triterpenic glycosides called momordicosides, such as momordicosides K and L (8-239). Bitter melon originated in India and is now widely cultivated in Asia and Africa. The plant also contains other biologically active compounds for which it is used to treat a number of diseases, such as toothache, diarrhea, furuncle and diabetes. 

Cucurtbitacins are tetracyclic compounds produced by plants of Cucurbitaceae family and humans sense their taste as bitter. Some specialized cucumber leaf beetles of can efficiently detoxify these compounds. Limonoids are a large group of oxygenated triterpenoids produced by plants in Rutaceae and Meliaceae famihes. 

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