Optimization in the extraction of polyphenolic compounds and antioxidant activity from Opuntia ficus‐indica using response surface methodology

The aim of this study was to find the optimal conditions for the extraction of phenolic compounds as well as antioxidant activities from Opuntia ficus-indica via the response surface methodology using a maceration extraction technique. A Box–Behnken 33 design was used to optimize the process variables (ethanol concentration: 70%, 83%, and 96%; temperature: 24, 50, and 76°C; time: 30, 75, and 120 min) in the extraction of phenolic compounds, and the DPPH• and ABTS•+ antioxidant activities. The Statgraphics Centurion XVII software used in this study predicted a maximal polyphenolic extraction and antioxidant activity when an ethanol concentration of 78.9%, a temperature of 75.9ºC, and an extraction time of 120 min were used. The experimental validation of these conditions resulted in an extraction of 0.907 ± 0.09 phenolic acids, and flavonoids (8.720 ± 0.27 mg QE/g), as well as that of DPPH• (0.160 ± 0.01) and ABTS•+ (0.612 ± 0.01) antioxidant activities. Practical applications No publications have evaluated the influence of factors such as ethanol concentration, temperature and time, and their interactions, on simultaneously optimizing the extraction of polyphenolic compounds and antioxidant activity from O. ficus-indica. Additionally, water and ethanol were used as solvents for the extraction of polyphenolic compounds; these are economical and recommended for their safe use in the food industry, in particular, to develop new functional foods.