Bioactive peptides from industrial pseudocereal amaranth and their pharmacological prospects

Amaranth, an underutilised pseudocereal, can yield bioactive peptides with antioxidant, antimicrobial, ACE‑inhibitory, DPP‑IV‑inhibitory, anti‑inflammatory, antithrombotic, and anticancer activities in preclinical models. However, translation is limited by low bioavailability, extraction challenges, incomplete sequence identification, and scarce clinical validation. This review summarises production methods, reported bioactivities, and future research priorities. Evidence supports potential, but clinical efficacy is not established. Future work requires optimised extraction, structure‑activity characterisation, in vivo studies, and clinical trials.

Introduction

Bioactive peptides are short protein fragments with biological activities beyond nutrition. They become active after proteolytic cleavage. Reported activities include antihypertensive, antioxidant, antimicrobial, antidiabetic, and anticancer effects. Amaranth is a nutrient‑dense pseudocereal with a balanced protein profile, making it a promising peptide source. This review evaluates its production methods, bioactivities, and industrial prospects.

Bioactive Peptide Types

• Antioxidant: Che late metals, donate electrons, enhance endogenous defences. Amino acids like methionine, histidine, and tryptophan are associated with activity.

• Antimicrobial: Small, cationic, amphipathic molecules that disrupt microbial membranes.

• Antihypertensive: Inhibit ACE, reducing angiotensin II and increasing bradykinin.

• Anticancer: Induce apoptosis, inhibit angiogenesis, stimulate immunity. Lunasin is a well‑known example.

• Immunomodulatory: Modify host defence; anti‑inflammatory peptides are of interest.

• Hypocholesterolemic: Bind bile acids, modulate lipid metabolism. Amaranth peptides inhibit pancreatic lipase.

Sequence Analysis and Production

Peptides are isolated by ultrafiltration, chromatography, and mass spectrometry (LC‑MS/MS, MALDI‑TOF). Bioinformatic tools predict activity. Production methods include enzymatic hydrolysis (most common), fermentation (e.g., lactic acid bacteria for lunasin), simulated gastrointestinal digestion, and genetic engineering (e.g., modified amaranthin with ACE‑inhibitory inserts).

Amaranth‑Derived Peptides and Activities

• ACE inhibition: ALEP, VIKP, LPP, VRP, and others show competitive inhibition.

• Antioxidant: Alcalase hydrolysates scavenge radicals and chelate iron.

• DPP‑IV inhibition: Glutelin‑derived peptides (60–80% inhibition) reduced blood glucose in diabetic mice.

• Anticancer: Tryptic glutelin digest induced apoptosis in HeLa cells; inhibited HT‑29 colon cancer proliferation.

• Antithrombotic: Hydrolysates inhibited thrombin and fibrinogen conversion.

• Anti‑inflammatory/anti‑atherosclerotic: Peptides reduced LOX‑1, ICAM‑1, and MMP‑9 in macrophages.

Limitations

Most evidence is from in silico, biochemical, or cell‑based studies; animal studies are limited; clinical trials are scarce. Stability, absorption, and interactions with food matrices are poorly understood. Research has focused on seeds; leaves and stems are understudied. Genotype‑dependent differences are rarely evaluated.

Future Directions

Priorities: optimised extraction; comparative genotype screening; structure‑activity studies; in vivo absorption and stability tracking; dose‑response, allergenicity, and toxicity assessments; scalable manufacturing; and randomised clinical trials.

Conclusions

Amaranth‑derived peptides show promising preclinical activities but do not establish clinical benefit. Practical development depends on improved extraction, structure‑activity characterisation, in vivo validation, clinical trials, and scalable processing.

Full text

https://www.xiahepublishing.com/2572-5505/JERP-2026-00006

The study was recently published in the Journal of Exploratory Research in Pharmacology.

Journal of Exploratory Research in Pharmacology (JERP) publishes original innovative exploratory research articles, state-of-the-art reviews, editorials, short communications that focus on novel findings and the most recent advances in basic and clinical pharmacology, covering topics from drug research, drug development, clinical trials and application.

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