Characterization of buffalo milk by 31P-nuclear magnetic resonance spectroscopy

We report here a 31P nuclear magnetic resonance (31P-NMR) investigation of buffaloes’ milk, milk ultrafiltrate, and phospholipids from milk fat; corresponding data were also acquired for cows’ samples. In milk samples, we identified glycerophosphorylcoline, glycerophosphorylethanolamine and inorganic orthophosphate resonances, together with a broad peak assigned to serylphosphate residues of casein. Ultrafiltrate samples of buffaloes’ milk showed the presence of several phosphorous signals and 10 of them (inorganic phosphate, phosphocreatine, glycerophosphorylcoline, glycerophosphorylethanolamine, N-acetylglucosamine-1-phosphate, glucose-6-phosphate, galactose-1-phosphate, phosphorylethanolamine, phosphorylcoline, and glycerol-1-phosphate) were unambiguously identified by addition of pure standards. In phospholipids fractions from buffaloes and cows’ milks, we clearly identified phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, and phosphatidylinositol. By comparing 31P-NMR data from buffaloes and cow’s milks, we concluded that the amount (% mol) of phosphorylated compounds correspond in both milks.