Structure-activity relationships of bioactive peptides derived from legumes: significance and perspectives

Legumes, esteemed globally for their rich protein content, eco-friendly lifecycle, and versatility in vegetarian, vegan, and flexitarian diets, have emerged as pivotal crops. Peptides derived from legumes, such as soybean, chickpea, pea, lentil, and peanut, can be obtained through various methods, including microbial fermentation and enzymatic hydrolysis, to exhibit several bioactivities, including antioxidant, hypoglycemic, antihypertensive, and anti-inflammatory effects. The structure of these peptides plays a crucial role in determining the bioactivities. However, comprehensive reviews or commentaries on the structure-activity relationship (SAR) of legume-derived peptides (LDPs) are currently lacking. In this review, an overview of the commonly used LDP preparation methods, the biological activities, and mechanisms underlying the SARs of the peptides are discussed. Notably, the degree of hydrolysis, molecular weight, and the amino acid hydrophobicity, basicity, aromatic degree, and position in the peptide chain (particularly at the N- or C-termini) can influence the structural conformation of LDPs to enhance their bioactivities. It was also observed that the impact of higher-order structures on the bioactivity and safety of LDPs has received limited attention in current research. Future research could harness advanced computational methods to explore more complex SARs of LDPs to attain improved applications of LDPs in functional food contexts.