Mushrooms betalains

The betalains are confined to ten families of the order Caryophyllales20 The only foods containing betalains are red beet (Beta vulgaris), chard (B. vulgaris), cactus fruit (Opuntia ficus-indica) and pokeberries (Phytolacca americana). They also occur in the poisonous mushroom Amanita muscaria but this is not a normal food source. The importance of the betalains as colorants is confined to preparations from red beet. 

Betalains occur in centrospermae, mainly in red beets, but also in some cactus fruits and mushrooms. They consist of red-violet betacyanins 540 nm) and yellow betaxanthins (Alliax 480 nm). About 50 betalains have been identified. The major betacyanin is betanin (Formula 9.14), glucoside of betanidin, which accounts for... 

There are several oxidative natural product biosynthetic pathways known to proceed via oxidative cleavage of an aromatic precursor. One of the best-characterized examples is the biosynthesis of the betalain family of pigments, found in plants of the Centrospermae order, and mushrooms of the Amanita and Hygocybe genera. 

Betalains are red (betacyanins) or yellow pigments (betaxanthins) of Centrospermae and the pilei of some mushrooms (Fig. 292). Examples are betanin (betanidin-5-glucoside), the pigment of red beets, and indicaxanthin a pigment of Opuntia ficus-indica flowers and of the fly agaric (Amanita muscaria). Betalains are derivatives of (S)-betalamic acid. In the formation of betacyanins (S)-betala-mic acid condenses with L-cyclodopa (D 22.1.3), in case of betaxanthins with some other amines or amino acids, e.g., L-proline (D 17). Betacyanins and betaxanthins attract pollinators if present in plant flowers (E 5.5.1) and animals... 

Pigments known as betalains occur in centrosper-mae, e. g., in red beet and also in some mushrooms (the red cap of fly amanita). They consist of red-violet betacyanins (Amax 540 nm) and yellow betaxanthins (Amax 480nm). They have the general structure ... 

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