Optimization Of Ultrasound-assisted Extraction Of Total Phenolics, Flavonoids And Their Antioxidant Capacities From Avocado Seed Using Response Surface Methodology

Abstract

This study aimed to investigate the response surface methodology (Central Composite Design) to optimize the extraction conditions of the ultrasound assisted extraction (UAE) of total phenolics, flavonoids, and their antioxidant capacities from avocado seed (Persea americana Mill.). The study employed a two step optimization approach, where significant factors were identified using One factor-at-a-time method (OFAT) with four factors (ethanol concentration, time, temperature, and solvent/solid ratio) and the optimal levels of the significant factors were determined using Central Composite Design. The factors that significantly affected the extraction yield of total phenolics were found to be ethanol concentration and temperature. The effects of these two parameters on the extraction efficiency were evaluated using a response surface methodology. The results showed that the optimal conditions for the simultaneous extraction of total phenolics, flavonoids, and antioxidant capacities were 53% ethanol concentration and ultrasound extraction temperature of 580C. Under these optimized conditions, the total phenolics, flavonoids, and antioxidant capacities were 43.31 ± 0.81 mg GAE/g DW, 7.74 ± 0.52 mg RE/g DW and 48.56 ± 1.03 mg AAE/g DW, respectively. The results demonstrate that the integrated ultrasound-assisted extraction method is an efficient and environmentally friendly method for the extraction of total phenolics, flavonoids, and antioxidant capacities from avocado seed