Betalain

Betalains are a group of chemically very similar water- bloom and fruit dyes, which form the third group of vegetable dyes in addition to anthocyanins and carotenoids. They occur exclusively in clove -like plants (other than Pink Family and Molluginaceae ) and agarics. Pharmacologically it is non-toxic alkaloids, which also have antioxidant properties, making them medically interesting. About 10 to 14 percent of the population can betalains not completely break down and excretes the dye in the urine (called Beturie as mainly occurring after drinking beetroot ). Chemically, it is the betalamic acid compounds with different ligands. Depending on the ligand, the betalains in the group of red-violet betacyans and the group of yellow betaxanthins can be divided.

Betalains can from other similar water-soluble dyes are distinguished by the fact that they break down in hot acid environment by their spectral and electrophoretic properties and.

In the 1960s, certain Wyler and others, the basic structure of betalains. The most important reactions betalain biosynthesis have been elucidated Also during this time. Betalainproduzierende plants are not able to flavan- 3 ,4 -diols in anthocyanidins convert, therefore, anthocyanins and betalains do not come together before.

In the biosynthesis of betalains first the amino acid tyrosine is then converted by a hydroxylase to dopa and betalamic acid. This then reacts with one hand, cyclo -dopa to betanidin, the starting material for all betacyans, or other with different amino acids or amines to various Betaxanthinen ( see figure). The variety of betacyans caused by different glycosylation and Acylisierung of Betanidins.

Betacyans

All betacyans have a purplish cast. The best known representative of betacyans is authorized in the food and cosmetic industry betanin ( beetroot ). Below is a list of other known betacyans:

• Amara thin. In flowers and leaves of many Amaranthaceae.
• Betanidin. In flowers of Mesembryanthemum ( ice plant family) and Portulaca ( Portulakgewächse ).
• Bougainvillein -r -1. In Brakten of bougainvillea.
• Celosianin II In Celosia and types of goose feet.
• Isobetanin. In fruits of Opuntia and phylloclades of Phyllocactus, as well as in flowers of Mesembryanthemum.
• Muscapurpurin. Component of the red color of the fruit body of the fly agaric.
• Prebetanin. In the skin of beet and fruits of Pokeweed.

Betaxanthins

All betaxanthins are yellow. Here are several well-known members of the group:

• Dopaxanthin. In flowers of Glottiphyllum ( Mesembryanthemum family).
• Humilixanthin. Add beets, Mesembryanthemum plants, Portulakgewächsen and Kermesbeerengewächsen.
• Muscaaurin I, II and VII component of the red color of the fruit body of the fly agaric mushroom, but also in beets.
• Portulacaxanthin I, II and III. In Portulakgewächsen.
• Vulgaxanthin I and II in beets.