“…Bioinformatic studies have become more and more popular in peptide’s design, particularly the quantitative structure–activity relationship (QSAR) study. QSAR models utilize a mathematical function to summarize the relationship between biological activities of a set of compounds and their structural characteristics. − So far, QSAR models have been successfully established for angiotensin-converting enzyme (ACE)-inhibitory peptides, antioxidant peptides, antimicrobial peptides, bitter peptides, antitumor peptides, etc. − To develop a QSAR model, a set of numerical descriptors is generated to characterize the structure of interest, e.g., amino acids, which serves as independent variables, while the biological activities are the dependent variables. Since the activities of peptides are determined by the amino acid compositions, sequences, and structures, a proper encoding technique should be employed for representing the sequence of amino acids.…”