Microwave Assisted Extraction of Phytoconstituents Used in Herbal Cosmetics

Phytoconstituents have proved to possess the potential to calm, smoothen, heal, rejuvenate and protect the skin. This has led to their increased use in cosmetics. Phytoconstituents are being extracted by microwave assisted techniques tremendously since last few years due to the advantages which they offer over conventional extraction techniques. Microwave assisted extraction (MAE)is a separation technique that combines the uses of energy of microwave radiation and traditional solvent extraction. It is not only time and solvent saving but also a boon to thermo labile constituents in plant material. Also, the dangers of hazardous organic solvents to nature, environment and operator are minimized due to lower amount of solvent required. MAE has shown to provide higher quality, purity and yield of phytoconstituents when compared to the conventional extraction techniques like Ultrasonic Assisted Extraction and Soxhlet extraction. It can be applied to solid, semi-solid and liquid matrices and the ability to alter and adjust solvent polarities renders it widely applicable. The phytoconstituents used in herbal cosmetics that have been reported to be extracted by MAE include lipids (fatty acids and oils), terpenes (essential oils, sterols, and carotenoids), polyphenols (flavonoids) etc. The aim of the study is to throw light on the potential and advantages of MAE and hence suggest its increased utilisation in the herbal cosmetics industry. A brief theory of microwave heating and the basic principles of using microwave energy for extraction have also been presented in this article.