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Abstract Ultrasound-assisted extraction (UAE) technology was used for extracting effective components from pomegranate (Punica granatum L. variety SisheKape-Ferdos) peel (POP). A response surface method was used to investigate the effects of independent process variables (ultrasonic amplitude (power control, UA): 20, 60 and 100%, and ultrasonic exposure time (UET): 5, 10 and 15 min) on the yield (Y) and antioxidant characteristics: total phenolic compounds (TPC), 1,1-diphenyl-2-picrylhydrazyl free radical scavenging (DPPH), ferric reducing-antioxidant power (FRAP), half maximal of radical-scavenging activity (IC 50) of aqueous pomegranate peel extract. According to Derringer's desired function approach, the optimal conditions based on both individual and combinations of all process variables were UA 60% and UET 6.2 min, and at this optimum condition, the predicted maximum values of Y, TPC, DPPH, FRAP, and IC 50 of the pomegranate peel extract (POPx) were 13.1%, 42.2 mg GA/g, 88.8%, 1824.6 μmol Fe2+/g, and 0.51 mg/mL, respectively. The experimental values were in a good agreement with the predicted values. Also, at optimal conditions, the minimum inhibitory concentration (MIC) of the extract (mean diameter of inhibition zone: 17.7 mm) showed that it had antifungal activities against Aspergillus niger. Highlights • Ultrasound-assisted extraction in water of bioactive compounds from pomegranate peel was optimized. • Antioxidant characteristics were affected by amplitude (UA) and ultrasonic exposure time (UET). • The optimal conditions based on both individual and combinations of all process variables were UA 60% and UET 6.2 min. • At optimal conditions, the extract showed adequate antifungal activities against Aspergillus niger. [ABSTRACT FROM AUTHOR]

Pulsed electric field (PEF) treatment was used for extracting effective components from Nepeta (Nepeta binaludensis Jamzad). A response surface method was used to investigate the effects of independent process variables (voltage of pulsed electric field (VPEF): 2, 4 and 6 kV cm-1 and number of pulsed electric field (NPEF): 20, 40 and 60 n) on the yield (Y) and antioxidant characteristics: total phenolic compounds (TPC), 1,1- diphenyl -2- picrylhydrazyl free radical scavenging (DPPHsc), ferric reducing-antioxidant power (FRAP), half maximal of radical-scavenging activity (IC50) of Nepeta extract (aerial parts). According to Derringer's desired function approach, the optimal conditions based on both individual and combinations of all process variables were VPEF 6 kV cm-1 and NPEF 60 n. At this optimum condition, the Y, TPC, DPPHSC, FRAP, and IC50 of the extract were found to be 11.36%, 417.85 mg GA g-1, 74.8%, 1688.53 µmol Fe2+ g-1, and 0.32 mg mL-1, respectively. The experimental values were in a good agreement with the predicted values. Also, the extract at optimal conditions of PEF (PEFopt-x) had a higher quantity of chlorogenic acid, caffeic acid, rutin, para-coumaric acid, rosemarinic acid, kaempferol, and apigenin compared with solvent extract. The addition of PEFopt-x to the purified soybean oil at the levels of 6% increased oxidative stability index (2.65 h) close to butylated hydroxy toluene (2.78 h). [ABSTRACT FROM AUTHOR]