Amaranth: A Pseudo-Cereal with Nutraceutical Properties

Abstract

Amaranth is a highly nutritious and non-allergenic crop with remarkable nutraceutical properties. Seed protein extracts following enzymatic digestion have been shown to inhibit Angiotensin Converting Enzyme (ACE). A possible mechanism of action of ACE inhibitor (ACEi) peptides involving the induction of Nitric Oxide (NO) production through endogenous Nitric Oxide Synthase (eNOS) activation has been proposed. The presence of lunasin, a peptide with proven antitumoral properties, has been confirmed in amaranth seeds and the gene encoding the amaranth lunasin peptide appears homologous to the bifunctional inhibitor/lipid transfer protein/seed storage 2S of the albumin family. Amaranth consumption has been shown to improve the plasma lipid profiles in animals. Methanolic extracts of amaranth have demonstrated anti-hyperlipidemic, anti-diabetic and anti-helmintic properties, while aqueous extracts have demonstrated anti-diarrheic, anti-fungal and anti-malarial properties. Specific polyphenols such as rutin, isoquercetin and nicotiflorin and some phenolic acids and amides with antioxidant effects have also been found in amaranth seeds. The aim of this mini-review is to provide an overview of the nutraceutical properties of amaranth.

Amaranth Protein Improves Lipid Profile and Insulin Resistance in a Diet-induced Obese Mice Model

“…Several studies using in vitro and in vivo systems have shown that amaranth presents activity against high serum lipid levels, insulin resistance, and weight gain due to its content of fatty acids and squalene, protein and starch quality as reviewed elsewhere [9]. Reports have proposed that amaranth protein could be responsible of those effects, since bioactive peptides delivered after protease activity in stomach and intestine, are absorbed into the bloodstream [10].…”

State of Knowledge on Amaranth Grain: A Comprehensive Review

“…Given the growing acceptance of amaranth in countries where its consumption has not been traditional because of the general consumer interest in grains with medicinal properties, literature reviews on amaranth have been published recently focusing on aspects such as the adaptation to traditional cuisines (Dixit and others 2011), or the nutraceutical properties of this non‐conventional grain (Huerta‐Ocampo and de la Rosa 2009). The present is a more comprehensive review that attempts to bring somewhat diverging studies on amaranth grain into a new perspective, with a special focus on its ability to modulate the metabolism and inhibit or delay pathological processes both in vitro and in animals and/or humans.…”

“…Most of these properties are explained by the presence of substances such as lunasin, a peptide with antitumoral effects, or of antihyperlipidemic, antidiabetic, and antihelmintic substances found in methanolic extracts, in addition to those with antidiarrheic, antifungal, and antimalarial properties found in aqueous extracts of the seeds (Huerta‐Ocampo and de la Rosa 2011). Specific flavonoids such as rutin and some phenolic acids as gallic acid, p ‐hydroxybenzoic acid and vanillic acid with antioxidant effects also occur in amaranth seeds and sprouts (Table 3) (Pasko and others 2008).…”

Grain Amaranths Are Defoliation Tolerant Crop Species Capable of Utilizing Stem and Root Carbohydrate Reserves to Sustain Vegetative and Reproductive Growth after Leaf Loss

“…Compared to cereals, amaranth seeds are notable for their high contents of gluten-free protein having a nutritionally balanced amino-acid composition [26], [33], [34]. Moreover, there is a growing awareness of the health-promoting properties of amaranth grain proteins and oil, which may be used for the prevention of some types of cancer, hypertension and high-lipid related disorders [35].…”