Brazilin (Bra)

Brazilin is a red pigment obtained from the wood of the brazilwood family (Caesalpinia sp), and is also known as Natural Red 24. Brazilin has been used since at least the Middle Ages to dye fabric, and has been used to make paints and inks as well. The specific color produced by the pigment depends on its manner of preparation: in an acidic solution brazilin will appear yellow, but in an alkaline preparation it will appear red. Brazilin is closely related to the blue-black dye hematoxylin, having one fewer hydroxyl group. Brazilein is the name for the oxidized pigment. There are many ways to extract and prepare brazilin. A common recipe, developed in the Middle Ages, is to first powder the brazilwood, turning it into sawdust. Then, the powder can be soaked in lye or a hot solution of alum, either of which extracts the color better than plain water alone.