OPTIMIZATION OF MICROWAVE ASSISTED EXTRACTION OF PHENOLIC COMPOUNDS FROM DECALEPIS HAMILTONII ROOT USING RESPONSE SURFACE METHODOLOGY

Abstract

Polyphenolic compounds comprising flavonoids and phenolic acids are widely distributed in foods of plant origin and counted to be the most abundant antioxidant in our diet. Due to its health benefitting properties they are of great interest in recent days. Decalepis hamiltonii is one such plant that is rich in phytochemicals having antioxidant properties and other beneficial medicinal value. Maximum yield of these phytochemicals during extraction requires optimized conditions of process parameters. In the present study, Microwave-assisted extraction (MAE) of polyphenols from the Decalepis hamiltonii roots was optimized using response surface methodology. The effect of independent variables such as extraction time (1, 3 and 5 min), solid to solvent ratio (0.5, 1.75 and 3 g/25ml solvent), solvent concentration (30%, 60% and 90% ethanol) and their interaction on Total Phenolic Content(TPC) and Total Flavonoid Content (TFC) were determined by three factor- three level Box-behnken Design. The highest TPC (0.03 mg GAE/mg DHRP) and TFC (0.08 mg RE/mg DHRP) were obtained under the optimum extraction conditions of 3 min, 2.56 gm/25 ml of solvent, 53.77 % ethanol and 2.15 min, 3 gm/25 ml of solvent, 49.18 % ethanol respectively. These findings further demonstrate that extraction of bioactive phytochemicals from plant materials using MAE method consumes less extraction solvent and saves time.