Gel Formation of Globin Prepared by Acid-acetone Method and Globin Hydrolyzates

Abstract

The gel formation of porcine globin prepared by the acid-acetone method and the acid hydrolyzates of the resulting globin were investigated. (1) Globin dissolved in acidic solution below pH 4.0 and in alkaline solution above pH 10.0, and was almost insoluble in the pH 7.0 to 8.0 region. (2) Globin gel was formed in the pH range 2.0-4.0 and 10.0-11.0, and at a globinconcentration above 7%. (3) Though globin formed the gel when citric acid was added in the range of 0.02M to 0.2M, the further addition of the acid, 0.4M to 2.0M, inhibited the gel formation. However, the transparent gel was formed when the solutions whose gel formation was inhibited were allowed to stand at 30°C for 10days. In the case of acetic acid and phosphoric acid, the effects of these acids on gel formation was similar to that of citric acid though acid concentration and the values of gel strength of the gel formed were different from those of citric acid, respectively. The hydrolysis of globinin these acids and SDS -PAGE of the resulting hydrolyzates were carried out. When the hydrolysis was done by these concentrated acids, the protein band of about 15 kDa which is thought to be globin was pale and the bands below 15 kDa, on the contrary, were dark. From the results, it is thought that the hydrolyzates produce a marked effect on the gel formation of globin. In addition, it was suggested that the proportion of globin to the hydrolyzates was closely correlated with the gel strength of the gel formed.