Botanical description
An upright shrubby plant growing 1–2 m tall with reddish-green stems, palmately lobed leaves (3–5 lobes), and pale yellow flowers with a dark red center. The most distinctive feature is the fleshy, bright crimson calyx that enlarges after flowering and surrounds the seed capsule. This is the part harvested for food and tea. The calyces are acidic and intensely red-purple.
Pharmacognosy intro
Hibiscus calyces are exceptionally rich in anthocyanins, principally delphinidin-3-sambubioside and cyanidin-3-sambubioside, which give the characteristic deep red color. Other constituents include organic acids (15–30% hibiscus acid/citric acid, malic acid, tartaric acid), flavonoids (quercetin, kaempferol, gossypetin), and polysaccharides. The calyces also contain modest amounts of protocatechuic acid and ascorbic acid.
Editorial orientation