Extraction of Bioactive Ingredients

Isolation of bioactive ingredients from the plant materials is a trial and error excise in which different solvents are tried under a variety of conditions such as time and temperature. The main objectives of the 

Jayaprakasha and Bhimanagouda S. Patil Vegetable Fruit Improvement Centre, Department of Horticultural Sciences, Texas A M University, 

Isolation of bioactive compounds involves dissolution of solutes from the plant matrix, diffusion of the compounds into the extractant, and separation of solutes using chromatographic techniques. 

In choosing a solvent for the extraction of bioactives, the ability to extract components has to be considered. For instance, ionic solutes can be extracted from aqueous solvents. The general features of the bioactive molecule that are helpful to ascertain the isolation process include partition coefficient, acid-base properties, chaige, stability, and molecular size. In literature, many basic extraction procedures are available [2], Solvent choice for the extraction is a critical step. Single solvent is unlikely to extract all groups of bioactive compounds from the natural plant materials. In most of the cases, these methods will be refined to our requirements in terms of plant materials and solutes of our interest. The expected outcome from this extraction process should be high purity product, adequate quantity of bioactive compound, and confirming the stereochemistry of the molecule. 

FIGURE 7.1. Schematic flow sheet of bioassay directed isolation, characterization ofbo-tanicals by successive extraction with different solvents. 

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