Carrot anthocyanins: nutrition, diversity and genetics

Purple carrots represent an excellent dietary source of anthocyanins. The consumption of these water-soluble flavonoid pigments is associated with various health benefits, attributed mainly to their antioxidant and anti-inflammatory properties. Anthocyanin pigmentation varies broadly among organs and tissues of the carrot plant and among carrot genetic stocks. The chemical structure of anthocyanin pigments conditions, to a great extent, their chemical stability and biological properties. Thus, variation among carrot stocks for total anthocyanin concentration as well as for pigment composition, particularly the relative content of acylated versus non-acylated anthocyanins, has practical importance for the production of chemically-stable food colorants and for using purple carrots as a dietary source of phytonutrients. Knowledge on the genetic basis of anthocyanin biosynthesis and modification (i.e., acylation and glycosylation) is expected to impact carrot breeding programs aiming at developing new varieties for both purposes; fresh consumption and the production of food dyes. This short review presents recent advances in the health-promoting effects of carrot anthocyanins, the characterization of purple carrot germplasm with regards to their pigment composition, as well as progress on the genetics underlying carrot anthocyanin pigmentation. The impact of these findings on carrot breeding programs for improving nutraceutical value is discussed.