PURIFICATION AND CHARACTERIZATION OF LACTOFERRIN, LACTOPEROXIDASE, LYSOZYME AND IMMUNOGLOBULINS FROM CAMELS MILK

Electrophoretic SDS-PAGE analysis of purified camel and bovine milk an d blood serum proteins revealed different migration patterns and molec ular weights. Camel blood serum was fractionated by precipitation with saturated ammonium sulphate (SAS); the optimal recovery of immunoglob ulins was at a concentration of 40% x 2 SAS. Isolation of bovine immun oglobulins, using an anion exchange resin such as DEAE-Sephacel was ea sier than for camel milk and serum since the difference in charge betw een the two subclasses of bovine immunoproteins IgG(1) and IgG(2) was greater. Protein-A chromatography was necessary as a first step follow ed by DEAE-Sephacel, for the purification of camel milk IgG(1) and IgG (2). Camel blood serum or milk IgG had high affinity to protein-A. How ever, secretory sIgA and IgM did not bind. Isolation of camel milk lys ozyme, lactoferrin and lactoperoxidase was carried out using a carboxy methyl-cellex cation exchange resin. Both camel milk lysozyme and lac toperoxidase were eluted at lower salt molarity than bovine proteins. Camel milk lactoferrin was eluted at higher molarity than bovine milk lactoferrin. Molecular weights of purified camel milk lysozyme, lactof errin and lactoperoxidase were estimated at 14.4, 79.5 and 78 kDa, res pectively; for bovine milk, corresponding values were 14.4, 76 and 72. 5 kDa respectively. The concentration of lysozyme in camel milk (15 mu g 100 mL(-1)) was higher than that in bovine milk (7 mu g 100 mL(-1)) . Immunological cross reactions between camel and bovine minor milk pr oteins were very limited.