Microwave-assisted hydrodistillation of essential oil from fennel seeds: Optimization using Plackett–Burman design and response surface methodology

Abstract

The study aims to optimize the microwave-assisted hydrodistillation (MAHD) of Foeniculum vulgare seed essential oil (FSEO), for the purposes of maximizing efficiency and reducing costs in terms of time and energy. Plackett–Burman design (PBD) was investigated to screen the six different variables affecting FSEO extraction and select the most significant ones. Response Surface Methodology (RSM) was used to evaluate the interactions of the significant parameters and to determine optimal conditions. MAHD and the traditional hydrodistillation (HD) techniques were compared in terms of extraction efficiency, economic and environmental impacts, and chemical composition of the FSEO. The optimum conditions of the studied responses were particle size less than 333.4673 μm, at the irradiation time of 20 min and a microwave power of 305.9282 W with a solid-liquid ratio of 0.1477 g/mL. Gas Chromatography (GC) analysis showed that the FSEO composition in MAHD and HD is similar with slight differences. Therefore, the results show that the microwave-assisted hydrodistillation method is an innovative, economical and environmentally friendly approach to efficiently and safely extract essential oil an economic and green innovative approach to extract efficiently and safely the essential oil (EO).