M.A. Thesis:

Extraction of phenolic compounds from marjoram and evaluation of antioxidant activity of the it's extract on stability of sunflower oil

There are several ways to prevent oxidation that one of these is the addition of synthetic antioxidants.But due to the adverse effects of synthetic antioxidants such as Asrjhsh and carcinogenesis in the human body, so investigate sources of natural antioxidants to replace synthetic ingredients seem essential. In this study, marjoram extracts were extracted.The phenolic compounds and free radical scavenging power percolation method extracts with concentrations ppm 50, 100, 200, 300 and 400 were measured using the Folin and DPPH. The results showed that the concentration of ppm 400 of Marjoram extract has antioxidant activity higher than BHT and lead to more stability in the soybean oil. Concentration ppm 400 was selected as the top level. The concentration and BHT were added to soybean oil and control samples were evaluated. Marjoram extract ppm 400 and BHT added to the amount due to the increase in antioxidant compounds, oxidative stability index increased oil and the peroxide level of oil acidity levels dropped TBA.

Keywords: .natural antioxidant, soybean oil, marjoram, oxidative stability