Antioxidant properties of hydro-alcoholic extract and extract of nepeta crispa in Lorestan province

Introduction: Antioxidants protect body against the oxidative stress caused by free radicals. This study aims at comparing the antioxidant properties of hydro-alcoholic extract and extract of Nepeta crispa (from its shoot part). Methods: The study was carried out in Lorestan University of Medical Sciences in 2012. Both hydro-alcoholic extract and essence of Nepeta crispa were prepared and antioxidant properties of samples were assessed using different methods. The ability to inhibit free radicals production was measured through 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. Total antioxidant capacity was measured using Phosphomolybdate Method. Likewise, phenol and flavonoid compounds of samples were measured using folinciocalteu Zishen method. Results: The results showed that the total antioxidant capacity of hydro-alcoholic extract and essence of Nepeta crispa were equal to 0.23±0.12 and 0.82±0.40 Nmol ascorbic acid per gram extract or essence. The phenol content of hydro-alcoholic extract and essence of Nepeta crispa were 254.63±15.75 and 6.94±1.37 mg gallic acid per gram extract or essence, respectively. Flavonoid content of hydro-alcoholic extract and essence of Nepeta crispa were equal to 5.53±0.34 and 0.36±0.06 mg quercetin per gram extract or essence, respectively. IC50 value (concentration that will inhibit 50% of free radicals production), hydro-alcoholic extract, essence of plant and Butylated hydroxytoluene (BHT), as positive control, were equal to 2.09±0.11, 6.05, and 3.88±1 μg/ml, respectively. Conclusion: The results showed that the hydro-alcoholic extract has better antioxidant properties in contrast to essence of Nepeta crispa. As a result, hydro-alcoholic extract of Nepeta crispa is a good and available source of antioxidant compounds which can be used, if useful, in food, pharmaceutical and industrial products.