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

Food Chem. 2011 Dec 1;129(3):1019-24. doi: 10.1016/j.foodchem.2011.05.066. Epub 2011 May 23.

Abstract

Peptides in the blood of subjects before and after collagen hydrolysate ingestion were fractionated by ion exchange and size-exclusion chromatographies and then derivatised with phenyl isothiocyanate. The derivatives were characterised by reserved phase (RP)-HPLC. Prolyl-hydroxyproline (Pro-Hyp), which has been identified in the previous studies, was detected as a major food-derived collagen peptide in the blood of all subjects (n=5). Another major peptide was identified as hydroxyprolyl-glycine (Hyp-Gly) in the blood of four subjects, which has not been detected in previous studies. The ratio of Hyp-Gly to Pro-Hyp depended on subjects and ranged from 0.00 to 5.04. Hyp-Gly was less susceptible to human serum peptidase than Pro-Hyp. Hyp-Gly enhanced the growth of mouse primary fibroblasts on collagen gels in a higher extent than Pro-Hyp. These findings suggest that Hyp-Gly plays a significant role in exerting the biological effects by ingestion of collagen hydrolysate.

Keywords: Collagen; Collagen hydrolysate; Fibroblasts; Hyp; Hyp-Gly; Peptide; Plasma; Pro-Hyp; Skin.