M.A. Thesis:

Extraction calendula persica flower and study of the antioxidant effect and stability on soybean oil in storage

Medicinal plants are valuable natural resources that developed countries pay special attention to them and are considered as raw material for conversing to useful medications for human beings. Antioxidants are compounds that prevent reaction of oxygen free radical effectively and reduce cell loss and death, cardiovascular diseases and cancers. In recent years, the role and useful effects of antioxidants against human diseases and spoil of food materials resulting from oxidation decay have attracted special attention. In this research ,at the first, marigold was extracted and its antioxidant and phenolic compounds were determined and then the extract in four concentrations( 100,200,400,800 ppm) added to soybean oil samples without antioxidant and samples of soybean oil formulated with this natural antioxidant under temperature of 65 ° C during 3 days storage were compared in terms of oxidative stability by peroxide value, tubarbutic acid index ,acidic value with soybean oil containing of 200 ppm synthetic antioxidant (BHT) and control sample, the results showed that the 800ppm concentration of marigold extract is more effective than(BHT) and 400 ppm concentration of marigold extract in stabilization of soybean oil during storage time because of higher contents of present antioxidants and phenolic compounds in 800 ppm concentration of extract than less concentrations of extract .

Keywords: Marigold, Soybean oil, synthetic, Antioxidant Compounds