SEPARATION OF MAJOR CASEIN FRACTIONS USING CATION-EXCHANGE FAST PROTEIN LIQUID-CHROMATOGRAPHY

Whole casein was separated into Beta-casein, kappa-casein, alpha-s1-casein, and alpha-s2-casein fractions using cation-exchange fast protein liquid chromatography. The gamma-caseins and several inidentified peaks were also separated. A urea-acetate buffer at pH 5 and a NaCl gradient from 0 to .26 M were used to separate the casein fractions. Several gamma-caseins and unidentified fractions eluted first, followed by three beta-casein peaks, several gamma-casein and unidentified peaks, kappa-casein, alpha-s1-casein, and alpha-s2-casein. Some gamma-caseins eluted with beta-casein. The four major caseins, which accounted for over 90% of the whole casein fractions, were accounted for with this method, and the calculated compositions correlated well with values obtained using anion-exchange fast protein liquid chromatography at pH 7.