Natural pigments are widely used in the food industry and have been studied extensively. Long before the art of food coloring, however, was the natural coloring of plants which surround us. Betalains are an example. DOPA-dioxygenase is the key enzyme involved in betalain biosynthesis. It converts 3,4-dihydroxyphenylalanine to betalamic acid, a yellow chromophore.
Betalamic acid has then the choice of two fates.
Betaxanthins and betacyanins are the two subclasses of betalain pigment. They are synthesized in the cytoplasm and then filtered out and stocked in vacuoles. The American botanist W.J.Hooker was the first to describe these plants in 1829 after an excursion to the Rio Desaguardero in South America. There are, in fact, a number of varieties of purslane which each express a very personal amount of betacyanins and betaxanthins. The pallet of colors is striking.