In vitro manipulation and propagation of medicinal plants

Well developed techniques are currently available to help glowers meet the demand of the pharmaceutical industry in the next century. These protocols are designed to provide optimal levels of carbohydrates, organic compounds (vitamins), mineral nutrients, environmental factors (e.g. light, gaseous e nvironment, temperature, and humidity) and growth regulators required to ob tain high regeneration rates of many plant species in vitro and thereby fac ilitate commercially viable micropropagation. Well-defined cell culture met hods have also been developed for the production of several important secon dary products. An overview of the regeneration of medicinal plants by direc t and indirect organogenesis and by somatic embryogenesis from various type s of explants is presented, and the use of these techniques combined with o ther biotechnological approaches to improve medicinal plants through somacl onal variation and genetic transformation is reviewed. (C) 2000 Elsevier Sc ience Inc. All rights reserved.