Yam (Dioscorea cayennensis) protein concentrate: Production, characterization and in vitro evaluation of digestibility

Abstract

This study aimed to produce a yam protein concentrate (YPC), Dioscorea cayennensis, to evaluate its protein digestibility and the peptide profile generated through simulated gastrointestinal digestion (GID). After concentration, the YPC that resulted in 64.0% protein was obtained. Simulated GID and free amino acids analysis were performed to evaluate its digestibility. For the peptide profile was evaluated by means of structure, molecular weight (MW) (nano-LC-ESI-MS/MS and SEC-FPLC), and hydrophobicity (RP-HPLC). Roughly 71.0% of peptides showed MW < 2 kDa after GID. The peptide sequences KQAVNENAINNARPLQPTN, GRSDPFLSDL, and KNEINAGVVDPNQLQF were identified in the gastric digestion. These sequences were further digested in the intestinal phase, yielding the NAINNARPL, GRSDPF, and VVDPN peptides. The GID process generated molecules with smaller MW, with consequent exposure of ionizable and functional groups, potentializing the yam proteins bioactive capacity. The peptides obtained after the digestion should be explored in future studies with the objective of understanding the bioactive potential of these molecules for human health.