Phytochemical analysis today includes the use of sophisticated analytical instrumentation by which direct identification of phytoconstituents from fresh plant parts, extracts, exudates, essential oils, and formulations is a straight forward task. However, the complex multi constituent composition of plants makes isolation and purification their active principles, still a challenging issue. An introduction to general principles…
It is an extensively used method of column chromatography for qualitative and quantitative analysis of complex mixtures of volatile substances that can be vaporized without decomposition. It was initially proposed by Martin and Synge in 1941 and later in 1952 developed by Martin and James for the separation of volatile fatty acids. Today it is…
Chromatographic separation performed with the stationary phase packed in a column as against being planar is column chromatography. The sorbents used in CC are taken in a column and the mobile phase instead of moving up by capillary action comes down due to gravity against the resistance of the sorbent. The mixture to be fractionated…
First referred to in 1938 by Russian workers Izmailov and Shraiber, the method known as TLC today was used by American Chemists Meinhard and Hall in 1949 for separation of volatile oil components. Work of Kirchner and his associates and demonstration of its extensive utility by Stahl in 1958 gave impetus to the development of…
Experiments that led to the development of chromatographic methods traceable to the early 19th century works of C.S. Schonbein, F. Goppelsroeder, R.E. Liesegang, and A. Martin used paper as the stationary medium. Martin and his collaborators used filter paper strips as carriers for the analysis of amino acid mixtures. Soon the technique was being used for…
Chromatography refers to a broad range of physical methods for the separation and/or analysis of complex mixtures of compounds. Plant drugs being constituted of multitudes of phytochemical groups, chromatographic techniques find immense application in their separation, processing, purification, and in qualitative and quantitative analysis. Developments in the field of chromatography have facilitated parallel rapid advancement…
Resins may be identified based on their physical and chemical properties. In addition, they may be identified by individual chemical tests to detect the presence of specific chemical constituents.
General method of separating resins is dependant upon the plant part associated with the resin, its preferred use, composition and its physical properties. While resins directly collected from the plants are natural resins (mastich, benzoin), those prepared from the plant parts by processing are called prepared resins (Podophyllin, Jalap resin).
Resins when separated and purified are often hard transparent or translucent hard, brittle solids or slightly soft semi-solids. They are heavier than water and by the action of heat they soften and fuse, yielding clear, adhesive fluids. Specific gravity of resins varies from 0.9–1.25. They are usually transparent when pure and become opaque when water…
Resins are amorphous solid products of a complex chemical nature. They are a heterogenous group with certain well-identified physical, chemical, and solubility characteristics. Resins are formed in schizogenous or schizolysigenous ducts or cavities by cells, which secrete a fluid composed of substances constituting gums, essential oils, and resins. Resin is held in solution by volatile…