IMMUNOLOGICAL CHARACTERIZATION OF BOVINE CASEIN FRACTIONATED BY FAST PROTEIN LIQUID-CHROMATOGRAPHY (FPLC)

Bovine caseins have been fractionated by FPLC on a Mono Q HR 5/5 colum n. The caseins were dissolved in bis-tris-propane buffer (pH 7.0), con taining 3.3 M urea and 14 mM of 2-mercaptoethanol and eluted in a step wise 0 to 0.4 M NaCl gradient. The FPLC elution profile of the bovine caseins resulted in 4 major fractions identified as kappa-, beta-, alp ha(s2)- and alpha(s1)-caseins. Immunological characterization of the i solated fractions has been performed by an indirect enzyme-linked immu nosorbent assay (ELISA) using polyclonal antibodies specific for bovin e caseins (anti-BC). The ELISA results demonstrated that the beta-case in fraction displays the highest antigenicity. Consequently, the use o f FPLC purified bovine beta-caseins would enhance the generation of mo noclonal antibodies suitable for the detection and quantification of b ovine milk in milk mixtures and dairy products.