Page 323 - Pharmacognosy 2 PG303

Pharmacognosy-2 (PG303) Level 2 Clinical Pharmacy-Pharm D

This group includes Resins (e.g., Colophony, Guaiacum, Jalap, Podophyllum,
and Scammony resins), Gum-Resins (e.g. Gamboge), Oleo-Resins (e.g. Copaiba,
and Male fern), Oleo-Gum-Resins (e.g. Myrrh, Asafoetida, Galbanum,
Ammoniacum, Olibanum and Mastic) and Balsams (e.g. Benzoin, Peru, Tolu and
Storax).

RESINS

Resins are hard, solid, or semisolid amorphous organic substance of complex
nature. They are insoluble in water, mostly insoluble in petroleum ether, but dissolve
more or less completely in alcohol, chloroform and ether, forming solutions which
on evaporation, deposit the resin as a varnish-like film. They are also soluble in
many other organic solvents as well as in fixed and volatile oils and in chloral
hydrate. Resins, on heating soften and finally melt. They burn with smoky flame.

Resins are obtained mainly by incision or by extraction with ethanol and
precipitation in water or by other methods.

Resins occur in plants either alone as in Guaiacum, or commonly associated
with volatile oils as in oleoresins e.g. Terpentine, Copaiba etc., or with gums as in
gum-resins e.g. Gamboge, or with gums and volatile oils as in oleo-gum resins e.g.
Myrrh, Asafoetida. Resins are found either in all elements of the drug e.g.,
Guaiacum resin, being present in all elements of Guaiacum wood or commonly in
special structures, i.e. in special cells, ducts, cavities or external gands.

Several resins are used in medicine. The following ones are official in the
Egyptian Pharmacopoeia: Resina Terebinthinae, Resina Guaiaci, Resina jalapoe,
Resina Podophylli, and Resina Scammonioe.

Colophony

Syn.: Colophonium; Resina Terebinthinae; Resina Colophonium Gallicum; Rosin.

Colophony is the residue left after distilling the volatile oil from the oleo-resin
obtained from Pinus palustris Mill., P. toeda L. and other species of Pinus (Fam.
Pinaceae).

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