5. Mastic
Synonyms Mastiche; Mastich; Balsam Tree; Pistachia Galls; Mastix; Lentisk; Mastisol;
Biological Source Mastic is the concrete resinous exudate obtained from Pistacia lentiscus Linne’ belonging to the natural order Anacardiaceae.
Preparation The resinous juice gets collected in cavities present in the inner bark. Fairly long incisions are made in the trunk and also in the larger branches, through which the resin exudes. The resin finally gets collected in the form of small tears on the outside. These are hand-picked and stored in dry place.
Characteristic Features It is a pale yellow or greenish yellow, globular, elongated or pear-shaped tears. It has a slightly balsamic odour and a terebene* taste. It is practically insoluble in water, but completely soluble in ethanol, chloroform (1g/0.5 ml), ether (0.1g/0.5 ml), partially soluble in oil of turpentine.
Chemical Composition Mastic contains 90% of a resin, comprising of mastichic acid (α-resin), which is soluble in ethanol and masticin (β-resin), which is insoluble in ethanol, and a volatile oil, 1 to 2.5%, that has the specific balsamic odour of the drug and largely contains (+)-pinene. A bitter principle is also present.
Uses
1. It is employed as an ‘enteric coating’ material in the formulation of tablets.
2. It is also used as a microscopical mountant.
3. It is widely used in the manufacture of varnishes.
4. Mastic is used in the form of a ‘dental varnish’ in dentistry to seal off cavities.
5. It is also used in tooth cements, plasters, lacquers, chewing gums and incense.
6. It is employed for retouching negatives.
---------------------------------------------------------------------
---------------------------------------------------------------------
* Terebene: A mixture of hydrocarbons prepared from oil of turpentine and sulphuric acid, used to make paints and varnishes and medicinally as an expectorant and antiseptic.
