Classical methodologies for preparation of extracts and fractions

Sample preparation is an important step in the whole process of analysis of bioactive compounds. For the preparation of extracts and fractions from marine organisms such as fungi, algae, bacteria, and invertebrates, there is a classical approach, which is currently the most used. After their isolation from the marine environment, the samples are subjected to an initial extraction. Since the chemical nature of the bioactive compounds in the resulting extracts is unknown, it becomes impossible to follow a general technique to separate the several classes of compounds in the extract. Therefore, the fractionation by solvent partition and the separation and purification by chromatography are two examples of the methodologies discussed for the separation of the mixture into fractions of pure bioactive compounds. Thus, this chapter focuses mainly on the classical approaches to prepare the extracts and fractions from marine organisms containing bioactive compounds with pharmaceutical and therapeutical interest.