Introduction

• Extraction is the separation of medicinally active portions of plant (and animal) tissues using selective solvents through standard procedures
• Such extraction techniques separate the soluble plant metabolites and leave behind the insoluble substances
• These include classes of preparations known as decoctions, infusions, fluid extracts, tinctures (an alcoholic extract), pilular (semisolid) extracts or powdered extracts.
• The basic parameters influencing the quality of an extract are the plant parts used as starting material, the solvent used for extraction, the manufacturing process used with the type of equipment employed, and the crude-drug to extract ratio.