From preparation to function: An updated review on hazelnut bioactive peptides and research prospects

Hazelnut, a globally significant tree nut, is rich in proteins that serve as ideal precursors for bioactive peptides. This review comprehensively summarizes the state-of-the-art in the production, biological activities, and structure-activity relationships of hazelnut-derived bioactive peptides. We discuss both conventional (enzymatic hydrolysis) and emerging in silico (bioinformatics) preparation approaches, highlighting their respective advantages in releasing and identifying novel peptides. The peptides exhibit a remarkable range of bioactivities, including potent antihypertensive (via ACE inhibition), antioxidant, anti-diabetic (via DPP-IV inhibition), anti-inflammatory, and anti-obesity effects. Critically, we elucidate how specific structural features—such as low molecular weight, and the presence of hydrophobic/aromatic amino acids at the termini—underpin these health-promoting properties. Future perspectives point towards the integration of conventional and in silico methods, leveraged by artificial intelligence and novel processing technologies, to accelerate the discovery and application of hazelnut peptides in functional foods and nutraceuticals for combating chronic diseases. • Hazelnut peptides demonstrate multi-functional health benefits • Molecular weight and terminal amino acids dictate potent bioactivity • Integrated conventional and in silico approaches enable efficient discovery • Hazelnut is a prominent source of DPP-IV inhibitory peptides • Future advancement requires AI, updated databases, and novel processing