Botanical description
Amaranth is an erect annual herb growing 0.5–2 m tall with broad, alternate leaves that may be green, red, or variegated. Tiny, inconspicuous flowers cluster in dense terminal or axillary spikes and produce very small, lens-shaped seeds (approximately 1 mm diameter) that range in colour from golden to cream, pink, or black depending on the variety.
Pharmacognosy intro
Amaranth grain is notable for its high-quality protein (13–18%) with a balanced amino acid profile including significant lysine, which is deficient in most cereal grains. The seeds contain squalene (2–8% in seed oil), phytosterols (β-sitosterol, campesterol, stigmasterol), and tocopherols. Leaf tissue is rich in betacyanin pigments (amaranthine, iso-amaranthine), flavonoids (rutin, quercetin), phenolic acids, and oxalates. Anti-nutritional factors include saponins, phytic acid, tannins, trypsin inhibitors, and lectins, though concentrations vary widely among cultivars and are significantly reduced by thermal processing.
Editorial orientation