Polyphenol oxidasePolyphenol oxidase (PPO; also polyphenol oxidase i, chloroplastic), an enzyme involved in fruit browning, is a tetramer that contains four atoms of copper per molecule. PPO may accept monophenols and/or o-diphenols as substrates. The enzyme works by catalyzing the o-hydroxylation of monophenol molecules in which the benzene ring contains a single hydroxyl substituent to o-diphenols (phenol molecules containing two hydroxyl substituents at the 1, 2 positions, with no carbon between).
BlueberryBlueberries are a widely distributed and widespread group of perennial flowering plants with blue or purple berries. They are classified in the section Cyanococcus within the genus Vaccinium. Vaccinium also includes cranberries, bilberries, huckleberries and Madeira blueberries. Commercial blueberries—both wild (lowbush) and cultivated (highbush)—are all native to North America. The highbush varieties were introduced into Europe during the 1930s. Blueberries are usually prostrate shrubs that can vary in size from to in height.
AstringentAn astringent (sometimes called adstringent) is a chemical that shrinks or constricts body tissues. The word derives from the Latin adstringere, which means "to bind fast". Calamine lotion, witch hazel, and yerba mansa, a Californian plant, are astringents, as are the powdered leaves of the myrtle. Astringency, the dry, puckering or numbing mouthfeel caused by the tannins in unripe fruits, lets the fruit mature by deterring eating.
ExtractAn extract (essence) is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol, oil or water. Extracts may be sold as tinctures, absolutes or in powder form. The aromatic principles of many spices, nuts, herbs, fruits, etc., and some flowers, are marketed as extracts, among the best known of true extracts being almond, cinnamon, cloves, ginger, lemon, nutmeg, orange, peppermint, pistachio, rose, spearmint, vanilla, violet, rum, and wintergreen.
PhenylpropanoidThe phenylpropanoids are a diverse family of organic compounds that are synthesized by plants from the amino acids phenylalanine and tyrosine. Their name is derived from the six-carbon, aromatic phenyl group and the three-carbon propene tail of coumaric acid, which is the central intermediate in phenylpropanoid biosynthesis. From 4-coumaroyl-CoA emanates the biosynthesis of myriad natural products including lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and phenylpropanoids.
ProanthocyanidinProanthocyanidins 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 tannins. Proanthocyanidins were discovered in 1947 by Jacques Masquelier, who developed and patented techniques for the extraction of oligomeric proanthocyanidins from pine bark and grape seeds.
Orange (fruit)An orange is a fruit of various citrus species in the family Rutaceae (see list of plants known as orange); it primarily refers to Citrus × sinensis, which is also called sweet orange, to distinguish it from the related Citrus × aurantium, referred to as bitter orange. The sweet orange reproduces asexually (apomixis through nucellar embryony); varieties of the sweet orange arise through mutations. The orange is a hybrid between pomelo (Citrus maxima) and mandarin (Citrus reticulata).
Biological pigmentBiological pigments, also known simply as pigments or biochromes, are substances produced by living organisms that have a color resulting from selective color absorption. Biological pigments include plant pigments and flower pigments. Many biological structures, such as skin, eyes, feathers, fur and hair contain pigments such as melanin in specialized cells called chromatophores. In some species, pigments accrue over very long periods during an individual's lifespan.
Tannic acidTannic acid is a specific form of tannin, a type of polyphenol. Its weak acidity (pKa around 6) is due to the numerous phenol groups in the structure. The chemical formula for commercial tannic acid is often given as C76H52O46, which corresponds with decagalloyl glucose, but in fact it is a mixture of polygalloyl glucoses or polygalloyl quinic acid esters with the number of galloyl moieties per molecule ranging from 2 up to 12 depending on the plant source used to extract the tannic acid.
ApricotAn apricot (ˈæpɹɪkɒt, ˈeɪpɹɪkɒt) is a fruit, or the tree that bears the fruit, of several species in the genus Prunus. Usually, an apricot is from the species P. armeniaca, but the fruits of the other species in Prunus sect. Armeniaca are also called apricots. Apricot first appeared in English in the 16th century as abrecock from the Middle French aubercot or later abricot, from Spanish albaricoque and Catalan a(l)bercoc, in turn from Arabic الْبَرْقُوق (al-barqūq, "the plums"), from Byzantine Greek βερικοκκίᾱ (berikokkíā, "apricot tree"), derived from late Greek πραικόκιον (praikókion, "apricot") from Latin [persica ("peach")] praecocia (praecoquus, "early ripening").
