Investigation of antioxidant properties of fenugreek

Free radicals with one or more unpaired electrons which are short-lived, unstable, and highly efficient molecules, cause oxidative damage to proteins, lipids, carbohydrates, and DNA. This damage, called oxidative stress, is reduced or eliminated by antioxidants in the cells and tissues that fight oxidation. Due to the carcinogenic effects of synthetic antioxidants which used in medicines and foods nowadays, studies on antioxidant phytochemicals that can replace them are being continued. Fenugreek is a plant of Fabales team of Fabaceae family which is located in a Trigonella species, that has broad adaptation ability. Fenugreek seeds contain a saponin, protein, essential oil and nicotine amide, mucilage, phosphorous compounds, phytin, choline, trigoneline, hydrolysis-producing diosgenin. Seeds have therapeutic properties thanks to steroidal saponins and antitumor, antiviral, antimicrobial, antioxidant properties. In this study, antioxidant activity was investigated by studying different parameters on extracts prepared from fenugreek seeds and powder using methanol, ethanol, water and ethyl acetate solvents. For this purpose, reduction power, metal chelating activity, total antioxidant activity, DPPH radical, ABTS•+ radical, DMPD•+ radical, hydroxyl radical scavenging activities, total phenolic substance content and ß carotene bleaching parameters were studied. Comparisons were made with some standard antioxidants (BHA, BHT, Ascorbic acid, α-tocopherol, catechin). According to the results obtained, the sweeping activity of the fenugreek, especially DPPH radical, ABTS•+ radical, DMPD•+ radical, was found to be high. These results indicate that because of its high antioxidant capacity, Fenugreek can be used instead of synthetic antioxidants in food.