Cucumber 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. 

Humans are very sensitive to some types of secondary products. The bitter taste of the alkaloid brucine (D 21.3), may be recognized in concentrations of 10 %, the odor of cucumber in a concentration of 10 %. The threshold concentrations are different in different persons and depend on the physiological state even in one and the same person. 

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... 

Kilham drops to all four limbs and chews on an Indian cucumber plant. A cub that he is raising comes over to sniff his mouth to learn that this is the smell of a food plant. Then the cub locates a plant with similar smell and begins eating it. This is the way bear cubs learn from their mothers which of the many choices of food are acceptable and safe. When they first encounter a plant, they hold the plant in their mouths before they eat or discard it. This is probably a survival behavior to check the taste of the plant to determine if it is edible. Bitter plants are usually toxic. 

Other distinguishing features Male flowers have 5 stamens, 4 in pairs and the fifth free. The pulp of the fruit tastes sour or bitter and is greenish-white with a large amount of cucumber-like placenta. 

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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