Production and characterization of lucrative hypoglycemic collagen-peptide-chromium from tilapia scale

Trivalent chromium (Cr3+) plays an important role in balancing blood sugar level. Among organic and inorganic chromium, the former has the higher bioavailability rate upon intake. Therefore, this study aims to transform inorganic chromium into organic form. Firstly, fish scale collagen peptide (FSC) was extracted from fish scale by enzyme hydrolysis with a 7% dosing ratio at pH 7.0 and 50 ℃ for 2 hr. Later, chelate containing inorganic CrCl3 was used to prepare organic collagen peptide-chromium (CCr) which was characterized to have a molecular weight of 666 Da. The optimal chelating conditions were determined at pH 3.0 and 60 °C for 1 hr, and chelation rate obtained was 90.6%. The resulting CCr was characterized by FTIR spectroscopy, and confirmed for retaining structure as type 1 collagen, and approved the Cr3+ bonding to the amine group of FSC at 700 cm−1 (Cr-N). In vitro test will be the next milestone for determining the reduction rate of chromium ion under simulated gastric- and gastro-intestinal tract conditions respectively to be addressed in the later communications.