Search results
Results from the WOW.Com Content Network
The main source of polyphenols is dietary, since they are found in a wide array of phytochemical-bearing foods.For example, honey; most legumes; fruits such as apples, blackberries, blueberries, cantaloupe, pomegranate, cherries, cranberries, grapes, pears, plums, raspberries, aronia berries, and strawberries (berries in general have high polyphenol content [5]) and vegetables such as broccoli ...
Others, such as some polyphenols and flavonoids, may be pro-oxidants in high ingested amounts. [23] Non-digestible dietary fibers from plant foods, often considered as a phytochemical, [24] are now generally regarded as a nutrient group having approved health claims for reducing the risk of some types of cancer [25] and coronary heart disease. [26]
Natural phenols are a class of molecules found in abundance in plants. Many common foods contain rich sources of polyphenols which have antioxidant properties only in test tube studies. As interpreted by the Linus Pauling Institute, dietary polyphenols have little or no direct antioxidant food value following digestion. [7]
New methods including the use of biosensors can help monitor the content of polyphenols in food. [29] Quantitation results produced by the mean of diode array detector–coupled HPLC are generally given as relative rather than absolute values as there is a lack of commercially available standards for all polyphenolic molecules. [citation needed]
The phenolic unit can be found dimerized or further polymerized, creating a new class of polyphenol. For example, ellagic acid is a dimer of gallic acid and forms the class of ellagitannins, or a catechin and a gallocatechin can combine to form the red compound theaflavin, a process that also results in the large class of brown thearubigins in tea.
Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a stilbenoid, a type of natural phenol or polyphenol and a phytoalexin produced by several plants in response to injury or when the plant is under attack by pathogens, such as bacteria or fungi.
Molecular structure of the flavone backbone (2-phenyl-1,4-benzopyrone) Isoflavan structure Neoflavonoids structure. Flavonoids (or bioflavonoids; from the Latin word flavus, meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans.
Proanthocyanidins are a class of polyphenols found in many plants, such as cranberry, blueberry, and grape seeds. Chemically, they are oligomeric flavonoids. Many are oligomers of catechin and epicatechin and their gallic acid esters. More complex polyphenols, having the same polymeric building block, form the group of condensed tannins.