Optimization of aqueous extraction conditions of phenolic and antioxidant compounds of Caper (Capparis spinosa) leaves and roots using response surface

Medicinal plant extracts contain effective compounds such as phenolic, antioxidant and antimicrobial. To extract the extracts from plants, traditional methods such as soxhlet and maceration or new nonthermal technologies such as ultrasound can be used. The type of extraction method affects the quantity and quality of the extract. The aim of this study was to evaluate the efficiency of using ultrasound in the aqueous extraction of phenolic and antioxidant compounds of Capparis spinosa leaves and roots. Response surface methodology (RSM) and Box–Behnken design were used to optimize the extraction factors, including extraction time (10, 25, 40 min) and sound intensity (40, 70, 100 %) with aqueous solvent. The results showed sound intensity was more effective factor than time. By increasing of sound intensity and the time of extraction the yield increased. The optimum conditions for extraction of phenolic and antioxidant compounds were as follows: extraction time 36 min and sound intensity 91 percent. Total phenolic content was obtained 21.80 mg/g in leaf and 14.96 mg/g in root and IC50 was obtained 11.75 µg/mg in leaf and 52.17 µg/mg in root.