Stability of an anticancer peptide isolated from Flathead by-products during in vitro gastrointestinal digestion

Background: Several peptides from seafood have shown effective anticancer activities. Nonetheless, one of the most significant challenges in developing fish peptides as functional food ingredients is proving their efficacy as anticancer agents. This study was aimed to evaluate the anticancer capacity and stability of a purified peptide (H. Met-Gly-Pro-Pro-Gly-Leu-Ala-Gly-Ala-Pro-Gly-Glu-Ala-Gly-Arg.OH) during a simulated gastrointestinal (GI) digestion.Methods: The anticancer activity of the peptide(s) before, during, and after GI digestion was analyzed against colon cancer cells (HT-29). Changes in cell morphology were assessed using an inverted microscope, while the degree of apoptosis was observed using a Muse Cell Analyzer.Results: Results showed little or no hydrolysis of the bioactive peptide by pepsin was observed, indicating the peptide was resistant to digestion in gastric conditions. The growth of HT-29 cells was significantly inhibited (P < 0.05) by the un-digested peptide and peptide(s) present in the digesta that was yielded by gastric and gastrointestinal digestion up to 28.89%, 29.68%, and 38.3%, respectively. HT-29 cells treated with pepsin and pancreatin digested peptides showed the highest cell death (3.54±2.30%).Conclusion: Overall, the findings showed that the purified peptide has the potency to be used in cancer therapy via oral administration and/or incorporation in food(s) applications for the treatment of specific cancer.Keywords: bioactive peptide; digestion; fish by-products; hydrolysis