Comparison of quantity and structures of hydroxyproline-containing peptides in human blood after oral ingestion of gelatin hydrolysates from different sources

Ohara H, Matsumoto H, Ito K, Iwai K, Sato K · Journal of Agricultural and Food Chemistry

Source material changes what reaches the blood. Hydroxyproline-containing peptides were ~30% of all detected Hyp, with Pro-Hyp the major constituent throughout — but total AUC was significantly higher for fish scale than porcine skin, and several peptides (Ala-Hyp, Leu-Hyp, Ile-Hyp, Phe-Hyp, Pro-Hyp-Gly) appeared ONLY after the fish-derived hydrolysates. Collagen sources are not interchangeable at the peptide level.

Population

Healthy male volunteers, single-blind crossover, 12 h fasted, 24 h sampling

Intervention

Type I gelatin hydrolysates from fish scale, fish skin, or porcine skin

Comparator

The three sources against each other

Limitations

Five subjects, surrogate endpoint, no joint outcome. Authors are at Meiji Seika Kaisha, a food company. Compares only type I sources, so it does not address type II.