Quinoa (ChenopodiumquinoaWilld.) –A Plant Species with Unique Nutritional Properties

Abstract

Quinoa ( Chenopodium quinoa Willd.) belongs to the family Amaranthaceae and is botanically related to spinach, beetroot, goosfoots, and amaranth. Although it is taxonomically and morphologically distinct from cereals, it is classified as a pseudocereal based on its use. It was one o f the staple foods of the civilizations in the Andean region of Latin America before the arrival of Spanish conquistadors, cultivated for over 7,000 years — mainly in present - day Peru, Bolivia, Ecuador, Chile, Argentina, and Colombia. Quinoa was used not onl y as food but also for medicinal purposes. Along with potatoes and maize, it was one of the three main dietary staples of the ancient Inca civilization. There is considerable genetic diversity among quinoa populations in terms of morphology, physiology, yi eld, chemical composition, and functional properties, depending on their geographic origin. Currently, more than 6,000 farmer - grown populations have been identified, and 16,422 quinoa accessions and wild relatives are stored in gene banks. This species has a high adaptive capacity to diverse and even extreme environmental conditions. In 2022, the highest grain production was recorded in Peru (113,376 tons), Bolivia (44,707 tons), and Ecuador (884 tons). The chemical composition of quinoa grain is unique. It is gluten - free and rich in amino acids that are rare in the plant world — lysine, methionine, and cysteine — and contains the albumin protein, which is identical to the albumin found in egg whites. One of quinoa’s most important features is its balanced profi le of essential amino acids. Based on its amino acid content, quinoa proteins are nutritionally superior to those in traditional cereals. Its grain contains more than twice as much lysine as wheat, maize, and rice, which is the highest value recorded among cereals and pseudocereals. Quinoa grains also contain a high percentage of polyunsaturated fatty acids, particularly omega - 3, - 6, and - 9, which are essential for human growth and development. They also have high levels of vitamin E (tocopherols: α, β, γ, δ) and tocotrienols (α, β, γ, δ), known for their strong antioxidant and biological activity. Due to this lipid profile, quinoa is considered an alternative to oil crops in some regions. Moreover, quinoa is rich in minerals such as potassium, calcium, magn esium, and phosphorus and contains dietary fiber in quantities similar to those found in whole grains. Quinoa contains a range of secondary metabolites with broad biological activity. At least 193 secondary metabolites have been identified over the past 40 years, including phenolic acids, flavonoids, terpenoids, steroids, and nitrogen - containing compounds. These metabolites exhibit various physiological functions, such as insecticidal, molluscicidal, and antimicrobial effects, as well as diverse biological activities, including antioxidant, cytotoxic, antidiabetic, and anti - inflammatory properties. Further research is needed to enhance the application of quinoa in the functional food industry, as well as in animal nutrition, medicine, and cosmetics. This pap er provides an overview of quinoa’s origin, significance, nutritional value, physiological functions, and role in human nutrition as a nutraceutical plant.