Distribution, Antioxidant Capacity, Bioavailability and Biological Properties of Anthocyanin Pigments in Blood Oranges and Other Citrus Species.

Anthocyanins are natural pigments that give a red, purple, and blue color to many plant, flower, fruit, and vegetable species. Their presence within the genus was first reported in 1916, and it is well-known that the red color of the flesh and rind of blood (red or pigmented) oranges ( L. Osbeck) is due to the presence of anthocyanins. They are also present in the young shoots, flowers, and peel of lemon ( (L.) Burm. f.), citron ( L.), and other citrus species. Since then, the scientific community has expressed increasing interest in studying their profile and distribution, with many published studies focused on the quali-quantitative pattern in the different vegetative tissues belonging to the genus . Moreover, with the discovery of their relevant antioxidant activity, owing to their ability to capture free radicals, much research has been performed in the last two decades on their radical scavenging power, in vitro and in vivo biological properties, and anticarcinogenic capacity, also focusing attention on their bioavailability for humans. The present work is intended as a comprehensive review of the advances in scientific research on anthocyanin pigments naturally occurring within the genus , including their natural distribution, antioxidant capacity, bioavailability, and biological value and properties. The scientific evidence herein reported can be used to further increase the knowledge of this class of compounds and represents a valuable and comprehensive contribution to promoting anthocyanin-rich citrus fruit consumption as a healthy dietary habit.