تخلیص بتالاکتوگلوبولین از شیر گاو و مطالعه آنتی ژنیسیته آن

          Beta-lactoglobulin (BLG) is a major whey protein in the milk of ruminants,    e.g. cows, and such non-ruminants as horses. This protein is resistant under    various conditions of pH and temperature. There is some evidence of    absorption of some intact BLG in humans. Infants being fed with cow’s milk-    based formulas are especially prone to develop adverse reactions against    proteins, including BLG, absorbed intact through their intestinal wall that is    more permeable than that of adults. Regarding its importance, purification    of BLG for immunological and serological studies and for setting up such    diagnostic tests as ELISA  and RAST is undoubtedly necessary. The aim of this    study was to introduce a simple, reproducible, fast and less expensive    method for BLG purification while saving its antigenicity, as well.           Whey (lactoserum) was prepared by isolating casein from defatted milk    using HCl. Globulins were then precipitated in whey by half-saturated    ammonium sulfate. The whey and precipitated globulins were used for    Sephadex G-50 gel filtration and diethyl aminoethyl cellulose anion    exchange chromatography. Using enzyme-linked immunosorbent assay    (ELISA), Western blotting and ELISA inhibition assay, antigenicity of the    purified protein was then evaluated.           In gel filtration, BLG was eluted with the second peak. In anion    exchange chromatography of ammonium sulfate precipitated proteins and    of whey proteins, it was eluted with the second peak.           Our results showed high purity and well-preserved antigenicity of BLG    thus purified.