Sun Hee Moon1,2, Jae Hoon Lee1, Dong Uk Ahn2,3, Hyun-Dong Paik1,4. 1. Department of Food Science and Biotechnology of Animal Resources, Konkuk University, Seoul 143-701, Korea. 2. Department of Animal Science, Iowa State University, Ames, IA 50011, USA. 3. Department of Animal Science and Technology, Sunchon National University, Sunchon 540-742, Korea. 4. Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea.
Abstract
BACKGROUND: Egg white proteins can be excellent substrates for the development of functional foods and nutraceuticals. In this study, several in vitro antioxidant methods, namely the β-carotene linoleate model system, the ferric thiocyanate method, the 2-thiobarbituric acid-reactive substances (TBARS) method and copper/calcium ion chelation, were used to determine the antioxidant capacity of natural and autocleaved ovotransferrin. RESULTS: Autocleaved ovotransferrin was prepared by reducing natural ovotransferrin with tris(2-carboxyethyl)phosphine (TCEP) for 6 h at 37 °C. Autocleaved ovotransferrin suppressed the discoloration of β-carotene effectively and prevented the oxidation of linoleic acid during 5 days of storage at 4 °C. However, the concentration of autocleaved ovotransferrin had no influence on its antioxidant effect. Similarly, the highest TBARS values were obtained from autocleaved ovotransferrin (>90%) and the lowest value in natural ovotransferrin (24%) during incubation at 37 °C for 48 h. The hydrolysates obtained from autocleaved ovotranferrin showed better copper/calcium-solublilizing activity than those from natural ovotransferrin. CONCLUSION: The results indicated that autocleaved ovotransferrin has the potential to be used as a natural antioxidant in foods.
BACKGROUND: Egg white proteins can be excellent substrates for the development of functional foods and nutraceuticals. In this study, several in vitro antioxidant methods, namely the β-carotene linoleate model system, the ferric thiocyanate method, the 2-thiobarbituric acid-reactive substances (TBARS) method and copper/calcium ion chelation, were used to determine the antioxidant capacity of natural and autocleaved ovotransferrin. RESULTS: Autocleaved ovotransferrin was prepared by reducing natural ovotransferrin with tris(2-carboxyethyl)phosphine (TCEP) for 6 h at 37 °C. Autocleaved ovotransferrin suppressed the discoloration of β-carotene effectively and prevented the oxidation of linoleic acid during 5 days of storage at 4 °C. However, the concentration of autocleaved ovotransferrin had no influence on its antioxidant effect. Similarly, the highest TBARS values were obtained from autocleaved ovotransferrin (>90%) and the lowest value in natural ovotransferrin (24%) during incubation at 37 °C for 48 h. The hydrolysates obtained from autocleaved ovotranferrin showed better copper/calcium-solublilizing activity than those from natural ovotransferrin. CONCLUSION: The results indicated that autocleaved ovotransferrin has the potential to be used as a natural antioxidant in foods.