Advisor(s)
Abstract(s)
Ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) of bioactive
compounds, peels from Opuntia engelmannii cultivar (cv.) Valencia were optimized by response
surface methodology. Randomized extraction runs were performed for each of the technologies
employed in order to build e ective models with maximum (bioactive molecules content and yield)
and minimum (antioxidant activity) responses. A 5-level, 4-factor central composite design was used
to obtain target responses as a function of extraction time (t), solid to liquid ratio (S/L), methanol
concentration (metOH), and temperature (T). Specific response optimization for each technology
was analyzed, discussed, and general optimization from all the responses together was also gather.
The optimum values for each factor were: t = 2.5 and 1.4 min, S/L = 5 and 5 g/L, metOH = 34.6 and
0% of methanol and T = 30 and 36.6 C, achieving maximum responses of 201.6 and 132.9 mg of
betalains/g, 13.9 and 8.0 mg of phenolic acids/g, 2.4 and 1.5 mg of flavonoids/g, 71.8% and 79.1%
of extractable solid and IC50 values for the antioxidant activity of 2.9 and 3.6, for UAE and MAE,
respectively. The present study suggested UAE as the best extraction system, in order to maximize
recovery of bioactive compounds with a high antioxidant activity.
Description
Keywords
Betalains By-products Extraction optimization Opuntia Phenolic compounds Response surface methodology (RSM)
Citation
Melgar, Bruno; Dias, Maria Inês; Barros, Lillian; Ferreira, Isabel C.F.R.; Rodriguez-Lopez, Antonio D.; Garcia-Castello, Esperanza M. (2019). Ultrasound and microwave assisted extraction of Opuntia fruit peels biocompounds: Optimization and comparison using RSM-CCD. Molecules. ISSN 1420-3049. 24, p. 1-16