Effect of cultivated area treatments and alcoholic and hydroalcoholic solvent on phenolic, tocopherol and antioxidant property content of Fenugreek leaf extract

Lipid oxidation is one of the main reasons for the decline of food and the production of free radicals, which lead to the formation of potential carcinogenic and toxic compounds in food. This factor has led to use the synthetic anti-oxidation in food for preventing oxidation, which recently harm and side effects of these antioxidants has also been confirmed in human health. One of the measures to prevent side effects of the use of synthetic anti-oxidation is extraction of anti-oxidation of food and fresh plant, which contains phenolic compounds and the antioxidant at a high level. In this study, the antioxidant power of fenugreek leaf extract in two Ardebil and Sari areas were studied. The extract was extracted by methanol and methanol / water solvent (50:50) which had been affected by the mixer method. The amount of phenolic and tocopherols compounds was measured by using Folin– Ciocalteu and alpha – tocopherol, respectively, as well as anti-oxidant power of extracts was measured by three tests of 2,2-Diphenyl-1-picrylhydrazyl (DPPH), beta-carotene-linoleic acid and oxidative stability index (OSI), and they were compared with the tert-butyl hydroquinone (TBHQ). The results showed that the extract extracted of fenugreek leaf in Ardebil area by methanol solvent, with amount of phenolic and high tocopherols, the percentage of free radical scavenging (DPPH) 62.50% at concentration of 900 ppm, 89.52% bleaching at beta-carotene system at concentration of 500 ppm and at OSI system with resistance to oxidation for 4.66 hours, had the highest anti-oxidant property. Also, in some cases, there was no significant difference between it and the synthetic antioxidant TBHQ statistically. So, fenugreek leaf had good antioxidant property, and kind of solvent, cultivated area and extraction method is effective on antioxidant power of the extracts.