Changes in composition and content of food-derived peptide in human blood after daily ingestion of collagen hydrolysate for 4 weeks

J Sci Food Agric. 2018 Mar;98(5):1944-1950. doi: 10.1002/jsfa.8677. Epub 2017 Oct 16.


Background: Daily ingestion of collagen hydrolysate for a long period improves skin and joint conditions. It has been speculated that the beneficial effects are exerted by food-derived hydroxyproline (Hyp) peptides, which are detected in human blood after single ingestions. In the present study, to investigate the effect of long-term ingestion of collagen hydrolysate on Hyp peptides profile in blood, the concentrations of Hyp-peptides in human blood before and after daily ingestion for a long period were examined.

Results: Hyp-peptides increased to a maximum level at 1 h after ingestion and reverted to their initial levels within 24 h during experimental period. Pro-Gly and Hyp-peptides such as Pro-Hyp-Gly, Pro-Hyp, Ile-Hyp, Leu-Hyp, Hyp-Gly, Glu-Hyp and Ala-Hyp were identified in the blood after ingestion of collagen hydrolysate at 4.5 g day-1 for 4 weeks. For the whole period, Pro-Hyp was the leading compound. The compositional rate of Hyp-Gly showed a tendency to increase, while that of Pro-Hyp tended to decrease after daily ingestion.

Conclusion: The present results indicate that daily ingestion of collagen hydrolysate for a long period can change compositional rate of Hyp peptides in human blood. This fact suggests that long-term ingestion of collagen hydrolysate might change exo- or endo-type protease activity in the digestive tract, which may consequently promote beneficial effects. © 2017 Society of Chemical Industry.

Keywords: Hyp-Gly; Hyp-peptide; Pro-Hyp; collagen hydrolysate; collagen peptide.

MeSH terms

  • Adult
  • Animals
  • Collagen / chemistry*
  • Collagen / metabolism*
  • Female
  • Gelatin / chemistry
  • Gelatin / metabolism
  • Humans
  • Middle Aged
  • Peptides / blood*
  • Peptides / chemistry
  • Protein Hydrolysates / chemistry*
  • Protein Hydrolysates / metabolism
  • Skin / chemistry
  • Swine
  • Young Adult


  • Peptides
  • Protein Hydrolysates
  • Gelatin
  • Collagen