Antioxidant Activity and Biochemical Screening of two Glycyrrhiza L. Species

Aims: Glycyrrhiza L. is one of the most widely used plants in traditional medicine since antiquity. For the determining of the biochemical composition and antioxidant activity of methanolic extracts of two Glycyrrhiza species different parts. Study Design: In the current study, antioxidant activities, essential oils and fatty acid compositions of root and aerial parts of G. iconica and G. flavescens subsp. flavescens were examined. To measure antioxidant activities of methanol extracts, different chemical methods were carried out. Place and Duration of Study: Department of Biology, Physiology and Biochemistry Research Laboratory (December 2011-November 2012). Methodology: The antioxidant capacity tests were designed to evaluate the antioxidant activities of methanol extracts of Glycyrrhiza species tested. The extracts will be executed for their possible antioxidant activities by five different test systems namely total antioxidant capacity (phosphomolibdat assay), beta-carotene/linoleic acid test system, free radical scavenging (DPPH), ferric and cupric ion reducing power (CUPRAC). Total phenolic and flavonoid concentrations of each extract were also determined by using both Folin-Ciocalteu reagent and aluminum chloride. Results: The root of G. iconica showed the highest activity in all methods. The major components of essential oils from Glycyrrhiza species were 1-pentylcyclobutene, naphtalene, hexahydro farnesyl acetone, phytol, dimethylamine and n-hexadecanoic acid. In fatty acid profiles of these two taxa, the main fatty acids were palmitic and linoleic acids. Conclusion: Our results showed that studied parts of two Glycyrrhiza species can be used as an easily accessible source of natural antioxidants that could be important in pharmaceutical industry.