The effect of hydrocarbon addition on the deamidation rate in immune whey proteins.

The influence of some hydrocarbons that are often used at different stages of immunobiological preparation's production as stabilizers of biological activity on the dynamics of nonenzymatic deamidation in proteins of immune whey against conditionally pathogenic microorganisms obtained by means of membrane ultrafiltration technology is investigated. Preparations of whey were incubated in 10 per cent solutions of glucose, fructose and sorbitol at the conditions similar to physiological ones (0.9% NaCl, pH 5.5) and temperature of about +4 degrees C and +35 degrees C for 7, 14 and 28 days. A sample dissolved in 0.9% NaCl (pH 5.5) without addition of hydrocarbons was used as a "control preparate". All explored substances brought about the suppressive effect on deamidation rate of asparaginyl residues whereas that of glutaminyl residues, on the contrary, was obviously increased. The possible reasons for these observations are discussed.