2. Ammoniacum
Synonym Gum ammoniac.
Biological Source It is a oleo-gum-resin exuded from the flowering and fruiting stem of Dorema ammoniacum, D. Don. and probably other species belonging to family: Umbelliferae.
Preparation The exudation of the milky-secretions obtained in the form droplets is usually caused by the beetles that puncture the fruiting stem of D. ammoniacum. While quite a few of these milkydroplets get hardened on the stem itself, and the rest falls on the ground. The solidified oleo-gumresinsare scrapped from the stem with a plant-knife and also collected from the droppings on the ground.
Characteristic Features The drug has an irregular, rounded tears, that are yellowish or browish outside and whitish from within; these are generally brittle when cold, but get softened on warming.
It is also found, in the form of mass i.e., agglomeration of small droplets. The mass is found to be darker in colour and less homogeneous.
It has a peculiar odour, slightly sweetish, bitter and somewhat acrid taste. The physical
characteristics are: mp 45-55°C and d 1.207. Its acid number varies between 60-80, whereas the saponification number ranges between 97-114. It is partly soluble in water, ethanol, ether, vineger, or alkaline solution. It readily forms an emulsion with water.
Chemical Composition Ammoniacum-the oleo-gum-resin consists of volatile oil (0.1-1.0%), resin (65-70%), gum (20%), moisture (2-12%), insoluble residue (3.5%) and ash (1%). Ammoresinol,a phenolic substance is the main constituent of the resin, which is a colourless crystal, mp 110°C. It also contains traces of salicylic acid.
Chemical Tests
1. Ammoniacum when triturated with water, it forms a white emulsion.
2. A portion of the above emulsion when treated with a solution of chlorinated soda gives a deep orange-red colouration.
3. A portion of the emulsion on being treated with a potash solution yields a yellow colour.
4. A portion of the emulsion when treated with a 0.1% (w/v) solution of FeCl3, it gives an instant violet colouration due to the presence of traces of salicylic acid.
Uses
1. It is an important ingredient of porcelain cements.
2. It is a stimulant, and secreted by the bronchial mucous surface, thereby disinfecting the secretions.
3. It is used in plaster-of-paris (POP) plasters as a stimulant to the skin.
4. It is also used as a disinfectant expectorant in chronic bronchitis amalgamated with excessive discharge.
