Abstract
Human serum albumin (HSA) is a mixture of human mercaptalbumin (HMA, reduced form) and nonmercaptalbumin (HNA, oxidized form), i.e., a protein redox couple. Therefore, commercial albumin preparations may also have a different degree on protein redox state. We examined the redox state of commercial albumin preparations from various sources by our HPLC method.
Eight kinds of commercial HSA preparations were obtained from Sigma Co. and from Calbiochem. Co. Those samples were analyzed by an HPLC system equipped with a Shodex-Asahipak ES-502N column. To determine the value for each fraction of albumin, the obtained HPLC profiles were subjected to numerical curve fitting.
An HPLC profile of HSA showed three peaks corresponding to HMA (reduced form), HNA-1 (reversible oxidized form) and HNA-2 (irreversible oxidized form), respectively. Product No. A1653 from Sigma was the product corresponding to Cohn Fraction five, which is a starting material from pooled sera. Values (%) for HMA, HNA-1 and HNA-2 were 37.6, 44.3 and 13.1%, respectively. In contrast, those values for the final product (A3782), which was prepared through lyophilized and defatted processes, were 12.7, 30.2 and 38.6%, respectively, and it was contained dimer remarkably (17.0%). These results suggested that the heterogeneity of redox state of commercial HSA preparations appears to occur during manufacturing process of HSA from large-scale pooled blood. [Jpn J Physiol 54 Suppl:S65 (2004)]
