Cranberry fruit (Vaccinium macrocarpon) grows on evergreen shrubs that are native to North America. Cranberry is a term derived from the contraction of ‘‘crane berry.’’ This name is derived from the nickname of the bilberry flower, which, when it withers, is similar in appearance to the head and neck of the sand crane, a bird that often feeds on the berries of this plant. The cranberry is part of the Ericaceae family and naturally grows in acidic swamps full of peat moss in humid forests. Cranberries are composed of water (88%), organic acids (including salicylate), fructose, vitamin C (high levels, i.e., 200 mg/kg of fresh berries), flavonoids, anthocyanidins, catechins, and triterpinoids. The chemical constituents responsible for their taste are the iridoid glycosides. The anthocyanidins and proanthocyanidins (PAC) are tannins (stable polyphenols) found only in vaccinium berries and function as a natural plant defense system against microbes. Common preparations with cranberries include fresh, whole berries, gelatinized products, juices (usually 10-25% pure juice) and capsules. Pure juice is too acidic (pH, 2.5) and unpalatable, even with sweeteners .Despite cranberry presentation, it is generally recommended to consume cranberries just prior or two hours after meals; it is also important to drink lots of water, mainly after preparations from dehydrated juices. Cranberry juice, predominantly in the form of a juice cocktail drink with approximately 25% cranberry juice, has been the traditional choice of most women seeking to prevent Urinary Tract Infections (UTIs). American cranberry has a complex and rich phytochemical composition, particularlyflavan-3-ols, A-type procyanidins (PACs), anthocyanins, benzoic acid, and ursolic acid. Cranberryflavan-3-ols are present as monomers, oligomers, and polymers). These oligomers and polymers are also referred to as PACs or condensed tannins and representw85% of the total flavan-3-ols on a weight basis. Cranberry is the main source of peonidin among 100 foods commonly consumed in the United States. Quercetin 3-galactoside is the predominant form, but at least 11 other glycosides are present in lower concentrations. Some of these, such as quercetin-3-acetylrhamnoside are rare in berries. In the Phenol Explorer database, the flavonol content of plant foods is usually <3 mg/100 g FW, although bilberry, black-berry, and blueberry contain 3.2–17 mg/kg. Cranberry fruit is classed as a functional food due to the naturally high content of compounds, such as polyphenols, which are believed to have antioxidant and therefore health-promoting properties. Health benefits of cranberry consumption range from cardio protective effects due to improved cholesterol profiles to aiding digestive health. Cranberry exists in various forms, including the raw fruit (fresh and dried), cranberry juice and cranberry extract in capsule/tablet formulations. Cranberry extract could be a potential alternative to antibiotics to treat acute uncomplicated UTIs. Proanthocyanidin (PAC) with A-type linkages, or their metabolites, is believed to be the active ingredient in cranberry, preventing Escherichia coli (E. coli) from binding to the bladder uroepithelium and thereby reducing the ability of E. coli to cause and sustain a UTI. Cranberries have also been found to improve lipid profile, improve endothelial function, and lower several markers of cardio metabolic risk. Nowadays, growing evidence suggests an important role of cranberries in maintaining digestive health. In addition to the anti-inflammatory effects, cranberries may also influence intestinal barrier integrity, which is another essential element of intestinal health. Cranberry was reported as the main source of peonidin among 100 foods commonly consumed in the United States. However, in the majority of studies, the total anthocyanin content is re-ported rather than amounts of individual anthocyanins. This approach may change because the bioavailability and health effects of anthocyanins seem to be affected by the structures of the aglyconesor the glycosidicmoieties . Quercetin 3-galactoside is the predominant form, but at least 11 other glycosides are present in lower concentrations. Some of these, such as quercetin-3-acetylrhamnoside are rare in berries. As shown in the Phenol Explorer database, the flavonol content of plant foods is usually <3 mg/100 g FW, although bilberry, black-berry, and blueberry contain 3.2–17 mg/kg.
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