Dual‐cooled microwave extraction of Foeniculum vulgare essential oil and its chemical composition and antibacterial activity: Comparison with hydrodistillation and conventional microwave

Abstract

Fennel (Foeniculum vulgare Mill.) is a herbaceous plant species (Apiaceae) native to Mediterranean and southern Europe, but now extensively naturalized in many regions of the word including Japan, Russia, India, and China. 1 Fennel seeds and their essential oils have been broadly applied in the areas of food production, cosmetic and pharmaceutical engineering, attributing to their special properties, such as the obvious abilities of flavouring, antioxidant, anti-inflammatory, antispasmodic and antimicrobials. [1][2][3][4][5][6] Thus, the development and research for fennel essential oils receives great attention.Fennel essential oils mainly contain trans-anethole, estragole, fenchone, limonene and α-pinene, which were proved to be the reason of its excellent antimicrobial activities. 6,7 However, the constitutes of fennel essential oils possess a remarkable variation, which is determined by the plant genotypes, plant development stage, location, climatic conditions, powder size and extraction technologies. [8][9][10][11] For example, the essential oil of fennel seeds from Tunisian