Anthocyanin pigments: Structure and biological importance
Anthocyanins are coloured water-soluble pigments representing one of the major subclasses of compounds. They rarely exist in nature as free aglycons, instead, they attach to one or more sugar moieties. Anthocyanins are found within different plant organs; flowers, leaves, fruits, roots, tubers and grains. They appear in different attractive colours depending on their structure, pH, and other factors. These compounds gained a lot of attention in the last few years as food colourants replacing chemical dyes, besides their role in enhancing plant tolerance against many abiotic stresses such as salinity, drought, excessive light, ultraviolet radiation and cold stress. Besides, previous studies demonstrated the importance of anthocyanins in human health and their protective properties against chronic diseases.