Original Articles: 2015 Vol: 7 Issue: 5
Green technology: Economically and environmentally innovative methods for extraction of medicinal & aromatic plants (MAP) in Egypt
Abstract
Extraction process forms the first basic step in medicinal plant research because the preparation of crude extracts from plants is the starting point for the isolation and purification of chemical constituents present in plants. Yet the extraction step remains often a neglected area, which over the years has received much less attention and research. Traditional methods of extraction and processing of herbs and medicinal plants such as solid liquid extraction (Soxhlet), steam distillation or cold press are still used in Egypt. These methods of extraction lack selectivity, give lower yields and because it uses large volume of organic solvents it present safety concern and environmental risk. Several new extraction techniques for improving efficiency and selectivity are now replacing the old methods of extraction. However, recently exports of medicinal and aromatic plants products from Egypt to other countries are becoming more and more restricted due to the presence of unacceptable levels of contaminants and occasionally the occurrences of heavy metals and pesticides that attributed to the drawbacks of traditional extraction methods. The fact that one single plant can contain several secondary metabolites makes the need for the development of high performance and rapid extraction methods an absolute necessity. Keeping in pace with such requirements, recent times has witnessed the use and growth of new extraction techniques with shortened extraction time, reduced solvent consumption, increased pollution prevention concern and with special care for thermolabile constituents. Novel extraction methods including Microwave Assisted Extraction (MAE), Supercritical Fluid Extraction (SCFE), Accelerated Solvent Extraction (ASE), Subcritical Water Extraction (SWE) and Ultrasound Assisted Extraction (USE) have drawn significant research attention in the last decade. In this review, we discussed the principles, affecting factors, advantages and disadvantages of traditional and innovative extraction techniques. We also suggested some ideas to establish these innovative technologies for extraction in Egypt.