ABSTRACT
Species from Monteverde, Costa Rica.......................... 298 8.5 Electrophoresis ............................................................................................................................. 301
8.5.1 The Basics ....................................................................................................................... 301 8.5.2 Agarose Gel Electrophoresis........................................................................................... 301 8.5.3 Polyacrylamide Gel Electrophoresis (PAGE)................................................................. 302
8.5.3.1 SDS-PAGE ....................................................................................................... 302 8.5.3.2 Nondenaturing PAGE....................................................................................... 303 8.5.3.3 Two-Dimensional Gel Electrophoresis............................................................ 303 8.5.3.4 Staining Techniques ......................................................................................... 304
8.5.4 Capillary Electrophoresis ................................................................................................ 305 8.5.4.1 Basic Modes of Capillary Electrophoresis ...................................................... 307 8.5.4.2 Selecting the Mode of Capillary Electrophoresis ........................................... 311
8.6 Conclusions .................................................................................................................................. 313 References .............................................................................................................................................. 313
It was estimated that about 80% of all the world’s medicines are originally derived from plant sources, especially those found in tropical regions. However, many of the plants within these often remote regions of the world have yet to be identified as species, and only about 15% of the known angiosperm species in these regions were examined for their medicinal potential. Therefore, there are most definitely a large number of plant-derived medicines and other useful compounds that have yet to be discovered and characterized around the world. While we discuss the social problems of environmental and plant conservation in other chapters (see Chapters 14 and 15
)
, the aim of this chapter is to give the reader an understanding of how one begins to determine what plants have useful compounds by looking at the process of plant collection, methods of extracting compounds, and general methods of separating plant compounds within crude extracts. In Chapters 9 and 10
,
we go on to explore how isolated compounds are characterized, with a focus on nuclear magnetic resonance (NMR) techniques and bioassays for the characterization of potential medical benefits.
