Abstract: Purpose: To prepare a calcium supplement for efficient absorption and utilization in the human body and to explore its effect on the osteogenic activity of MC3T3-E1 cells. Methods: Bovine bone peptide was chelated with calcium, and the optimal reaction conditions were determined by response surface methodology (RSM). The structural characteristics and stability of peptide-calcium chelate were studied by infrared spectroscopy, X-ray diffraction and atomic absorption spectrometry. The effects of bovine bone peptide-calcium chelate on the proliferation, differentiation and mineralization of MC3T3-E1 cells were investigated. Results: The optimum conditions for the preparation of bovine bone peptide calcium chelate were peptide/calcium mass ratio 2.97, temperature 62.54 ℃ and pH 9.06. Under these conditions, the calcium chelating capacity was 55.65 μg/mg. The results of spectral analysis showed that amino nitrogen, hydroxyl oxygen and carboxyl oxygen were the major calcium-chelating sites. Bovine bone peptide could form coordinate bonds with calcium, and the molecular mass of the peptide increased after chelation with calcium. In addition, the stability of bovine bone peptide-calcium chelate was little affected by temperature, but sensitive to pH. The peptide-calcium chelate could significantly promote the proliferation, differentiation and mineralization of MC3T3-E1 cells. Conclusion: Bovine bone peptide-calcium chelate has the potential to promote the osteogenic activity of MC3T3-E1 cells.

Key words: bovine bone peptide-calcium chelate; structural characterization; MC3T3-E1 cells; osteogenic activity