The chelating peptide (GPAGPHGPPG) derived from Alaska pollock skin enhances calcium, zinc and iron transport in Caco-2 cells

Gly-Pro-Ala-Gly-Pro-His-Gly-Pro-Pro-Gly (GPAGPHGPPG), a chelating peptide derived from Alaska pollock skin, has been approved with outstanding ability to chelate calcium, zinc and iron ions. In this study, the stability of GPAGPHGPPG during invitro gastrointestinal enzymatic digestion, the potential binding site between peptide and metal ions as well as its effects on mineral transport in Caco-2 cells were investigated. Results showed that approximately 75% of GPAGPHGPPG remained intact at the end of the invitro gastrointestinal enzymatic digestion. The formation of peptide-metal complex was potentially related to histidine and cyclic structure in terms of dehydration. Moreover, GPAGPHGPPG revealed significant promotional effects on calcium (112.7%, P < 0.01), zinc (32.3%, P < 0.01) and iron (27.7%, P < 0.01) transport in Caco-2 cell monolayer. In conclusion, GPAGPHGPPG could be developed as a potential functional ingredient to prevent mineral deficiency.