Preparation and Characterization for Peptide-Chelated Calcium of Deer Bone

The deer bone peptides (DBP) was used to chelate with Ca2+ to form the deer bone peptides chelated calcium (DBPCC), which could be a calcium nutraceutical supplement. The optimal condition for the chelation reaction was that 1.535 mg mL(-1) DBP reacted with 7.5 mmol L-1 CaCl2 at pH 7.0 and 40 degrees C for 15 min. Negatively charged amino acids, positively charged amino acids and hydrophobic amino acids in the DBPCC were probably important to the chelation reaction. And the DBP could chelate with Ca2+ through metal-binding sites (carboxyl oxygen atoms and amino nitrogen atoms). The Ca2+ would cause the DBP folding and conformation modification. Furthermore, the DBPCC was stable under ileum conditions (pH 7.0, 37 degrees C), indicating that it would be well absorbed in the human body and had the potential to improve the traditional calcium nutrition fortifier.