Isolation, Purification and Compositional Analysis of Antibacterial Peptides from Bovine Bone Collagen

Bovine bone collagen was hydrolyzed by neutral protease, and then the hydrolyate was separated and purified using ultrafiltration and gel chromatography. The antibacterial peptides obtained were analyzed by reverse high-performance liquid chromatography(RP-HPLC) and matrix-assisted laser desorption/ionization cascade time of flight mass spectrometry(MALDI-TOF-TOF-MS). The results showed that the ultrafiltration fractions with molecular weight less than 10 kD had strong antibacterial activity against Escherichia coli. The peaks I and IV isolated by Sephadex G-25 gel chromatography had strong antibacterial activity. By RP-HPLC and MALDI-TOF-TOF-MS analysis, the peak I contained a variety of peptides with molecular weight between 850 and 1550 D, whereas the peak IV contained fewer peptides between 700 and 900 D.