Identification of a novel food-derived collagen peptide, hydroxyprolyl-glycine, in human peripheral blood by pre-column derivatisation with phenyl isothiocyanate

Shigemura Y, Akaba S, Kawashima E, Park EY, Nakamura Y, Sato K · Food Chemistry

Identified a second major food-derived collagen peptide in human blood alongside Pro-Hyp: hydroxyprolyl-glycine (Hyp-Gly). It proved more resistant to human serum peptidase than Pro-Hyp and enhanced mouse fibroblast growth on collagen gels MORE than Pro-Hyp did. The Hyp-Gly to Pro-Hyp ratio varied enormously between individuals, from 0.00 to 5.04.

Population

Human volunteers before and after collagen hydrolysate ingestion

Intervention

Collagen hydrolysate, with blood peptides fractionated and characterised by RP-HPLC

Limitations

Five subjects, surrogate endpoint. The person-to-person variation in which peptide dominates is itself unexplained and unstudied — it may matter for who responds to collagen, and nobody has followed it up. Cell work is mouse fibroblasts, not chondrocytes.