Isolation, structure elucidation and DFT study on two novel oligosaccharides from yak milk

• Two novel oligosaccharides were isolated from Yak milk.
• The structure of novel oligosaccharides were elucidate with the help of spectroscopy.
• Geometry of all novel oligosaccharides were studied with the help of DFT.

Two novel oligosaccharides were isolated from yak milk. The milk was processed by the method of Kobata and Ginsberg involving deproteination, centrifugation and lyophilization followed by gel filtrate chromatography acetylation and silica gel column chromatography of derivatized oligosaccharides while their homogeneity was confirmed by HPLC. The structures of these isolated oligosaccharides were elucidated by chemical transformation, chemical degradation, 1H, 13C NMR, 2D NMR (COSY, TOCSY and HSQC) and mass spectrometry. The geometry of compound A (Bosiose) and B (Bovisose) have been optimized at B3LYP method and 6-311 + G(d,p) basis set. The difference between the energies of A and B is 1.269 a.u. or 796.309 kcal/mol.

Figure optionsDownload as PowerPoint slide