Microwave-Assisted Extraction in Natural Products Isolation

Microwave-assisted extraction (MAE) or simply microwave extraction is a relatively new extraction technique that combines microwave and traditional solvent extraction. Application of microwaves for heating the solvents and plant tissues in extraction process, which increases the kinetic of extraction, is called microwave-assisted extraction. MAE has a number of advantages, e.g., shorter extraction time, less solvent, higher extraction rate and lower cost, over traditional method of extraction of compounds from various matrices, especially natural products. The use of MAE in natural products extraction started in the late 1980s, and through the technological developments, it has now become one of the popular and cost-effective extraction methods available today, and several advanced MAE instrumentations and methodologies have become available, e.g., pressurized microwave-assisted extraction (PMAE) and solvent-free microwave-assisted extraction (SFMAE). This chapter provides an overview of the MAE and presents a number of specific protocols for natural products extraction.