Comparison of the qualitative composition of Laurus nobilis leaves extracts obtained by supercritical fluid extraction and microwave-assisted extraction

Along with traditional methods for processing aroma plants, such as steam distillation or extraction with organic solvents, novel alternative approaches are developed which provide the means for a more effective isolation of biologically active compounds from plant matrices and simultaneously possess ecological attractiveness. Supercritical fluid extraction and microwave-assisted extraction can be attributed to such approaches. Their implementation into routine practice is partially hampered by somewhat vague understanding of applicability areas of these methods as well as by the lack of knowledge on the influence of process parameters on the result. In this work, we performed a comparison of the applicability of supercritical fluid and microwave-assisted extraction techniques for the isolation of biologically active compounds from leaves of Laurus nobilis L. It was shown that microwave-assisted extraction allows obtaining oil containing only volatile terpene components. Supercritical fluid extraction allows isolation of not only volatile terpenes from laurel leaves, but a broader spectrum of compounds including eugenol derivatives, phytosteroids and tocopherols. Qualitative composition of supercritical fluid extracts is virtually independent on process parameters, only quantitative differences in component proportions are registered.