Optimization of Ultrasound-Assisted Phenolic Extraction from Red Pepper Seed by Response Surface Methodology

Abstract

In this study, phenolic compounds of Kahramanmaraş red pepper (Capsicum annuum L.) seeds which are waste products from red pepper processing line were extracted by ultrasound-assisted (UAE) and conventional solvent extraction (SE) methods. Two different extraction methods were evaluated in terms of total phenolic contents (TPC) and antioxidant capacity. Response surface methodology (RSM) was used to optimize UAE conditions of phenolic extracts including extraction temperature (40, 50 and 60 °C), extraction time (20, 40 and 60 min) and solvent volume (50, 75 and 100 mL) for obtaining maximum total phenolics with higher antioxidant capacity. Effects of temperature, time and volume of solvent on extraction of phenolics were evaluated. As a result of RSM analysis, the optimum conditions determined as an extraction temperature of 51 °C, an extraction time of 60 min, and solvent volume of 50 mL. The results showed that ultrasonic treatment was more effective than conventional extraction method on phenolic extraction yield.