betalain

chemistry

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June 22, 2026

Quick Summary

Betalains are a class of red to blue pigments found in plants, similar to anthocyanins. They are water-soluble and located within the vacuoles of plant cells. The color of betalains can change depending on the acidity or alkalinity of the cell sap, appearing red in acidic conditions, violet in neutral conditions, and blue in alkaline conditions.1

While anthocyanins are widely known, betalains are also responsible for the coloration of many flowers and fruits. They can also be found in roots, such as in beets. Betulinic acid, a crystalline triterpenoid acid, is found in various plants and is obtained from betulinol by oxidation.12

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Amaranthaceae
Physical description
…of the presence of characteristic betalain pigments. The small flowers can be bisexual or unisexual and are often borne in dense spikes; several leaflike bracts usually are present below each flower. The fruit may be a capsule, utricle, nutlet, drupe, or berry. Many species in the family are C₄ plants,…
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…of the presence of characteristic betalain pigments. The small flowers can be bisexual or unisexual and are often borne in dense spikes; several leaflike bracts usually are present below each flower. The fruit may be a capsule, utricle, nutlet, drupe, or berry. Many species in the family are C₄ plants,…
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Caryophyllales
Evolution
…group of pigments, known as betalains (betacyanins and betaxanthins) occurs only in some families of Caryophyllales. Species that possess betalains never contain anthocyanins and vice versa. Because the betalains are apparently restricted to this order, their presence has assumed some taxonomic significance as perhaps linking all families with betalains. It…
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…group of pigments, known as betalains (betacyanins and betaxanthins) occurs only in some families of Caryophyllales. Species that possess betalains never contain anthocyanins and vice versa. Because the betalains are apparently restricted to this order, their presence has assumed some taxonomic significance as perhaps linking all families with betalains. It…
Read More