Selection And Purification Of Natural Antioxidants From Raw Materials

In this study, total phenol content of 18 kinds of fat-rich foods were determined. The order from high to low by polyphenol content was oil-tea seeds> walnut> pistachios> sunflower> rapeseed> Torreya. Radicals scavenging experiments showed that polyphenols extracted from rapeseed, oil-tea seeds, walnuts, sunflower has strong antioxidant capacity. Optimization of extraction process of the four polyphenols by the factors of temperature, solution concentration, extraction time and solid-to-liquid ratio, and the optimal extraction conditions were determined. Five components from rapeseed polyphenols can be separated by 95% ethanol, flowing rate at 1mL/min through Sephadex LH20 chromatography. Purification of sunflower polyphenol was succeeding in the conditions of:95% ethanol eluent, flowing rate of 0.8mL/min, and it was separated into three components. The optimal purification conditions of oil-tea seeds t separation was 70% ethanol by the flow rate at 0.8mL/min, and four components can be separated. Both of the first components separated from sunflower polyphenol and oil-tea seeds polyphenol whose weight were tested by mass spectrograph at a value of 266.14 and 266.38 respectivly, show a better free scavenging capacity than Vc, TBHQ and BHA.