Optimization of Aqueous and Alcoholic Extraction of Phenolic and Antioxidant Compounds From Caper (Capparis spinosa L.) Roots Assisted by Ultrasound Waves

Background: Herbals are rich in effective compounds such as phenolic and antioxidant. Various methods are developed to extract these compounds, including Soxhlet, maceration, microwave, and ultrasound. The extraction method affects the quantity and quality of materials. Objectives: The current study aimed to investigate the effect of ultrasound in phenolic and antioxidants compounds extraction from Caper roots. Methods: Response surface methodology (RSM) and Box-Behnken design were used to optimize the two extraction parameters, including extraction time (10, 25, and 40 min) and ultrasound power (40%, 70%, 100 %) by aqueous and alcoholic solvents. Results: Based on the results, ultrasound power was more effective than the extraction time. A direct association was observed between ultrasound power and the extraction time with the total extraction. The optimum aqueous and alcoholic extraction condition for phenolic and antioxidant compounds extraction were as follow: extraction time 36 min and ultrasound power 91 percent. Total phenolic content was obtained 14.96mg/gwith aqueous solvent and 17.24mg/gwith alcoholic solvent, and IC50 was 52.17g/mg with aqueous solvent and 40.20 g/mg with alcoholic solvent. Conclusions: Overall, alcoholic extracts had more phenolic and antioxidant compounds than aqueous extracts.