Quercetin, kaempferol and apigenin in roselle (Hibiscus sabdariffa L.)

Roselle has been characterized by its intense red color due to the anthocyanins content. However, anthocyanins are mainly destabilized with sunlight and pH changes, causing a color change due to the oxidation of their double bonds or functional groups, which give them their biological activity of powerful antioxidants. The copigments, which are found within the structures, can be phenols that prevent oxidation and that are more biochemically stable because they stabilize and stop oxidation. The roselle of various colors ordered from higher to lower concentration of flavonoids are: Tecoanapa>Rosaliz>Alma Blanca>Sudan>Cotzalzin.