Abstract: Human serum albumin obtained by gene manipulation techniques can be purified by a combination of specified steps in which a culture supernatant obtained from a human serum albumin-producing host is subjected to ultrafiltration, heat treatment, acid treatment and another ultrafiltration, followed by subsequent treatments with a cation exchanger, a hydrophobic chromatography carrier and an anion exchanger, and by salting-out to thereby obtain a pure form of human serum albumin which contains substantially no proteinous and polysaccharide contaminants, which is formulated into a pharmaceutical preparation. The thus obtained human serum albumin can further be purified by treating recombinant human serum albumin with a hydrophobic chromatography carrier at pH of 2 to 5 and a salt concentration of 0.4 to 1 and exposing the carrier to a pH of 6 to 8 and a salt concentration of 0.01 to 0.

Abstract: A method for decoloring a recombinant human serum albumin by treating the albumin with a reducing agent is disclosed. Also, a method for decoloring a recombinant human serum albumin by treating the albumin with a method removing free polysaccharides with a cation exchanger followed by heat treatment is disclosed. The present invention provides a recombinant human serum albumin, coloring of which is fully suppressed by preventing binding of certain coloring components, which are contained in the raw materials or contaminants secreted by a microorganism, to human serum albumin so as not to cause coloring of the human serum albumin.

Abstract: Human serum albumin obtained by gene manipulation techniques can be purified by a combination of specified steps in which a culture supernatant obtained from a human serum albumin-producing host is subjected to ultrafiltration, heat treatment, acid treatment and another ultrafiltration, followed by subsequent treatments with a cation exchanger, a hydrophobic chromatography carrier and an anion exchanger, and by salting-out to thereby obtain a pure form of human serum albumin which contains substantially no proteinous and polysaccharide contaminants, which is formulated into a pharmaceutical preparation. The thus obtained human serum albumin can further be purified by treating recombinant human serum albumin with a hydrophobic chromatography carrier at pH of 2 to 5 and a salt concentration of 0.4 to 1 and exposing the carrier to a pH of 6 to 8 and a salt concentration of 0.01 to 0.

Abstract: A method for suppressing coloring of human serum albumin expressed by genetic engineering, which comprises culture and/or purification in the presence of an amine compound selected from the group consisting of alkylamines, diamines, guanidines, benzamidines, basic amino acids, and aminophenylacetic acids. According to the present invention, coloring of HSA expressed by genetic engineering can be suppressed to from one-half to one-tenth of that without treatment for coloring suppression. In addition, HSA can be recovered in high yields, and the treatment of the invention does not affect the inherent properties of HSA.