Comparative evaluation of different extraction methods for the assay of phytochemicals and antioxidant activity of Valeriana officinalis roots

Background & Aim:Medicinal plants are rich sources of substances with nutraceutical and health benefits. Valeriana officinalis L. (Valerianaceae) is a known medicinal plant used in traditional medicine throughout the world. The present study aimed to evaluate the efficiencies of three methods for antioxidant extraction from Valeriana officinalis, and the impact of extraction methods on total phenollic and flavonoids contents and antioxidant activities of valeriana root was studied. Experimental: The dried-root was extracted by three different methods including maceration, ultrasonic assisted, and Soxhlet assisted extraction. Antioxidant capacity of the extracts was assessed using DPPH and nitric oxide (NO) free radicals scavenging, reducing power and iron chelating activity. Total phenolic and flavonoid contents were also identified. Results: The ultrasonic extract showed the highest amount of total phenolics and flavonoids contents. In DPPH radical scavenging activity and reducing power assay, the ultrasonic assisted extract, (IC50=0.546 mg/ml) showed higher activity than the other extracts. In DPPH radical scavenging activity, IC50 for ultrasonic extract, soxhlet assisted extraction and maceration extract were 0.546, 0.816 and 0.678 mg/ml, respectively. The results clearly showed that the extraction methods used in this study significantly affected antioxidant capacities and total phenolic and flavonoids contents. It was found that ultrasonic assisted extraction and Soxhlet methods are more efficient in extraction of antioxidant components from Valeriana officinalis L. Recommended applications/industries: Considering result of study, it can be inferred that the herb may be a good source of bioactive compounds and can work as an antioxidant to prevent the oxidative deteriorative activity of food materials.