Study on stability and antioxidant activity of the yellow pigments from Eurotium cristatum

Abstract:

[Objective] Stability and antioxidant activity of the yellow pigments from Eurotium cristatum were evaluated. [Methods] Taking preservation rate of the pigments as an indicator, the effect of different temperature, light and pH on the stability were assessed. Antioxidant activity of the yellow pigments was investigated by three methods: reducibility, DPPH· scavenging activity and inhibition of erythrocyte hemolysis induced by H2O2. [Results] The results of stability test showed that preservation rate of the pigments was more than 98.88% after low-temperature treatment for 7 days and declined as the temperature increasing. Light, especially sunlight, resulted in an obvious loss of stability of the pigments. Better stability of the pigments was observed in the range of pH 2?10. However, preservation rate was lower than 46.22% at pH 12. At low concentration the pigments had higher reducibility, DPPH· scavenging activity and inhibition rate of erythrocyte hemolysis than VE, and the hemi-inhibitable concentration (EC50) to DPPH· was lower than 50 mg/L. [Conclusion] The yellow pigments from Eurotium cristatum had better stability in the condition of heat and acid but alkali and sunlight were not. What′s more, the pigments had higher antioxidant activity.