Manufacture of oligopeptides containing branched-chain amino acids from the perspective of site complementation: A combination of peptidomics and chemometrics strategy

Abstract

Target peptides containing branched-chain amino acids (BCAAs) possess various proven physiologic functions, yet there has been a limited focus on the manufacturing processes associated with these peptides. Herein, target BCAA-containing oligopeptides were purposefully produced from biomacromolecules via the site-complementary perspective based on the combination of peptidomics and chemometrics strategies employing Antarctic krill rich in BCAAs as the material. Based on peptidomics profile and principal component analysis, a portfolio of 566 peptides, with the number and abundance percentage of target oligopeptides being 80.74% and 86.50% respectively, was identified from protein hydrolysate by papain, establishing papain as the most suitable cutting tool under single-enzymatic hydrolysis. Terminal amino acid frequency and chemometric analysis further revealed that alcalase, when employed in conjunction with papain, complemented the hydrolysis of papain and significantly enhanced the content of BCAAs from 13.27% to 15.00% within the target peptides. Another portfolio of 411 peptides was identified, accounting for 90.75% in number and 90.36% in abundance percentage for target oligopeptides, demonstrating strong radical scavenging capacities. This investigation provided a comprehensive understanding of the intricate relationship between enzymatic conversion and the molecular composition of target peptides at a molecular scale, which not only contributed valuable insights into the manufacturing processes but also proposed a promising strategy for the rational combination of proteases in the production of target peptides.