Liquid Chromatography for Plant Metabolite Profiling in the Field of Drug Discovery

Although medicine has undergone massive evolutions, challenges are still present. Technological evolutions have had a major influence on the drug discovery process. As a consequence, this process nowadays has become much more rationalized than it used to be in its early days. However, in the end, substances are still screened for their ability to interact with pathophysiological processes in a trial-and-error approach. With chemical synthesis, we are now able to create chemicals with various related structures, which are then subjected to screening tests. In some cases, active compounds are found, which then go through a long process of characterizing their properties and turning them into drugs. However, many of the synthesized compounds do not make it to a final drug substance. To rationalize the drug discovery process, researchers often rely on earlier knowledge. One strategy is to explore the active substances in herbal products with known applications in traditional medicine, hoping that the active compounds are different from those currently used in the treatment of a given pathology, or allow treatments of health issues that could not be treated effectively before. Because of the complexity of herbal products, high requirements are set on the sample preparation and chemical separation techniques to create a metabolite profile, which is then processed chemometrically to find potentially active compounds. In this chapter an overview is given of the sample preparation and chemical separation techniques that are often used to develop such metabolite profiles (or fingerprints) and of the data handling approaches applied to indicate the active compounds.