Microwave assisted extraction of essential oils from enzymatically pretreated lavender (Lavandula angustifolia Miller)

In this study, microwave assisted a hydrodistillation process (MWHD) of essential oils from lavender (Lavandula angustifolia Miller) was investigated. In order to examine any potential differences in essential oil extraction, the lavender flowers underwent enzymatic pretreatment. A 2(3) factorial design of experiments, combined with statistical methods of data analysis were used to optimize enzymatic pretreatment and to evaluate the influence of major variables (enzyme concentration, temperature and pH) on the performance of the microwave assisted extraction. Under optimal conditions, an extraction yield of 24 mg oil g(-1) substrate was achieved (an increase by approximately 25% in comparison with the classic extraction conditions of conventional hydrodistillation). The main compounds of the essential oils obtained were analyzed and identified by gas chromatography coupled to mass spectrometry (GC-MS). Analyzing the data obtained indicated that the content of main compounds (linalool and linalyl acetate - 73%) was greater than that obtained by conventional extraction (67%).