Betalain

Betalains are a class of red and yellow tyrosine-derived pigments found in plants of the order Caryophyllales, where they replace anthocyanin pigments. Betalains also occur in some higher order fungi. They are most often noticeable in the petals of flowers, but may color the fruits, leaves, stems, and roots of plants that contain them. They include pigments such as those found in beets. The name "betalain" comes from the Latin name of the common beet (Beta vulgaris), from which betalains were first extracted. The deep red color of beets, bougainvillea, amaranth, and many cacti results from the presence of betalain pigments. The particular shades of red to purple are distinctive and unlike that of anthocyanin pigments found in most plants. There are two categories of betalains: Betacyanins include the reddish to violet betalain pigments. Among the betacyanins present in plants include betanin, isobetanin, probetanin, and neobetanin. Betaxanthins are those betalain pigments which appear yellow to orange. Among the betaxanthins present in plants include vulgaxanthin, miraxanthin, portulaxanthin, and indicaxanthin. The physiological function of betalains in plants is uncertain, but there is some evidence that they may have fungicidal properties. Additionally, betalains have been found in fluorescent flowers, though their role in these plants is also uncertain. Gelber und roter Mangold.JPG|[[Swiss chard]], showing one plant expressing yellow betaxanthins and another expressing red betacyanins. Cactus in Bloom 01.jpg|Flowers of the [[cactus]] ''[[Mammillaria]] sp.'' contain betalains. Amaranthus caudatus0.jpg|Inflorescences of ''[[Amaranthus caudatus]]'' (love-lies-bleeding) contain large quantities of betacyanins. Betalains (betacyanins) were first isolated and its chemical structure discovered in 1960 at the University of Zurich by Dr. Tom Mabry. It was once thought that betalains were related to anthocyanins, the reddish pigments found in most plants. Both betalains and anthocyanins are water-soluble pigments found in the vacuoles of plant cells.