Dr. Amit Gangwal,
Smriti college of pharmaceutical education, Indore
Plant remains to be the enviable source of molecules of therapeutic significance. Since antiquity, these bio resources have been in use for variety of diseases in different part of the world. Regardless of the type of plant, targeted ailment or other such parameters, the one step which is one of the most important and common is removal of the molecule or fraction or part there of from the plant biomass. Several new methods besides the usual organic solvent extraction have been developed over the last few years for the extraction of primary and secondary metabolites. These are alcohol extraction with various biocompatible solvents, recovery of carboxylic acids and antibiotics with reactive extraction, dissociation extraction, aqueous two-phase extraction, and supercritical and near critical fluid extraction. Extraction and re-extraction processes are integrated into a single step by emulsion liquid membrane and solid supported liquid membrane extractions.