Recent advances on the biological activities of purple sweet potato anthocyanins

Purple sweet potato is one of the main food crops in the tropical and subtropical areas. Purple sweet potato is abundant in anthocyanins, starches, non-starch polysaccharides, caffeoylquinic acid derivatives, vitamins and minerals. Among these components, anthocyanins have been considered as the major biological molecule and are responsible for deep purple color in purple sweet potato. The main chemical structure of purple sweet potato anthocyanins (PSPAs) includes cyanidins and peonidins in the form of monoacylation and diacylation. Owing to heat resistance and ultraviolet stability, PSPAs possess potential applications in the fields of food, cosmetics and pharmaceuticals. Moreover, PSPAs have attracted increasing attention due to their antioxidant, anti-inflammatory, anti-cancer, hypouricemic, hepatoprotective, hypolipidemic, hypoglycemic and neuroprotective activities. This review summarizes recent advances on the health-promoting activities of PSPAs, which will provide a theoretical basis of PSPAs for the development of functional foods.