Optimization of antioxidant activity and total polyphenols of dried apricot fruit extracts (Prunus armeniaca L.) using response surface methodology

Apricot is a natural source of polyphenols and other phytochemicals such as β-carotene and ascorbic acid that contribute to its antioxidant activity. Various organic solvents such as hexane, ether, methanol, and ethanol are used to obtain fruit extracts for different purposes. However, to extract the vital phytochemicals from a fruit, an efficient solvent along with certain other process parameters could reduce the process inputs thereby increasing the process efficiency. Response surface methodology (RSM) was employed to optimize the conditions for antioxidant potential and polyphenols from apricot powder (Prunus armeniaca L.) using four independent variables: methanol (20%, 35%, 50%, 65% and 80%), solvent/sample ratio (10, 15, 20, 25 and 30), temperature (20, 30, 40, 50 and 60 °C) and time (20, 30, 40, 50 and 60 min). The results showed that antioxidant potential and total polyphenols in the experiments varied from 76.15% to 96.68% and 8.77 to 12.11 mg GAE/g, respectively. The F-values for antioxidant potential and total polyphenols were 0.99 and 4.44, respectively. The coefficients of determination (R2 values) for antioxidant potential and total polyphenols were found to be 0.4799 and 0.8057, respectively. Under the optimum conditions of 35% methanol, 15 solvent/sample ratio, 30 °C temperature and time 30 min, the values for antioxidant potential and total polyphenols were 91.165% and 10.702 mg GAE/g, respectively. The present process could be employed on a commercial scale for the extraction of antioxidants from apricot fruits for their nutraceutical and other applications.