Page 135 - Pharmacognosy 02-06203

Uses:
Food industry as thickening purposes.

Resins and resin combinations

Natural resins are secretion or exudates of plant produced normally or
pathologically. They are sticky water-insoluble substances that are secreted
where a plant is damaged by incision or naturally preventing entrance of
pathogenic microorganisms and excessive loss of sap.

Physicochemical characters of resins:
State: solid or semi-solid viscous substance.
Color: clear to translucent yellow or brown.
Solubility: it is insoluble in water, soluble in alcohol.
Soften by heat and burn with a smoky flame.
They are the productof metabolism and consist of substances of different chemical
classes: acids, alcohol, phenol, esters or neutral inert compounds.

General methods for preparation of pharmaceutical resin:
-Collecting the natural product exuding from the plant.
-Extracting with alcohol.
-Separating the oil from oleo-resin by distillation.
-Heating the plant part containing the resin.
Fossil resins: natural resins from ancient trees chemically altered by long exposure
ex. Amber and copal.

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