Effect of extraction methods on yield, phytochemical constituents and antioxidant activity of Withania somnifera

Withnaia somnifera (L.) is a wonder herb with multiple medicinal properties. Its root is used in the preparation of many Ayurvedic medicines. Withanolides, steroidal lactones, present in the root are active chemical markers, however, phenolics, and flavonoids have also been reported in the root of this plant. In most of the herbal preparations, water extraction is carried out using the infusion or decoction preparation process. In the present study, extract yield, phytochemical constituents such as total phenol and withanolide content of water and water-alcohol extracts prepared using two most commonly used extraction techniques, also known as “Green Extraction” techniques, ultrasound and microwave assisted solvent extraction were compared with the conventional extraction method. Antioxidant activity of the extracts was also determined using DPPH and ABTS methods of antioxidant assay. Extract yield, chemical composition of the extracts (total phenol and withanolide content) and antioxidant activity of the extracts varied with the extraction process as well as solvent composition.