Page 326 - Pharmacognosy 2 PG303
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Pharmacognosy-2 (PG303)                              Level 2                Clinical Pharmacy-Pharm D

              Constituents
                     Colophony contains about 84 % of total abietic acids, about 5-6 % of resene,
              0.5 % of volatile oil and traces of a bitter substance.

              Uses
                     Colophony  has  stimulant  and  diuretic  properties.    It  is  used  chiefly  as  an
              ingredient of ointments and plasters, of some varnishes, paint dryers, printing inks
              and floor coverings.


                                                   Guaiacum Resin

              Syn.:  Resina Guaiaci; Rating Khashabel Anbeya

                     Guaiacum  resin  is  the  resin  obtained  from  the  heart  wood  of  Guaiacum
              officinale L., and of G. sanctum L. (Zygophyllaceae).

              Preparation
                     Most of the resin of commerce is produced in the following way from the
              trunk of the tree, the heartwood of which contains from 20-25 % of resin. A log of
              the wood is supported in a horizontal position above the ground by two upright bars.
              Each end of the log is then set on fire, and, a large incision having been previously
              made in the middle, the melted resin runs out there from in considerable abundance,
              or one end of a log of wood is raised, and the fire is applied to it, when the melted
              resin will run out of a groove cut in the other end, and may be received in potsherds
              (Block resin).  The resin may also be obtained in the form of tears by incisions made
              into the trunk.  The resin is also prepared by extracting the wood with alcohol.

              Description
                     Guaiacum resin occurs usually in large blocks, or sometimes in rounded or
              ovoid tears often covered with a dull green powder, fracture, brittle, vitreous, thin
              splinters, transparent from yellowish green to reddish-brown. When powdered, it is
              greyish but becomes green on exposure to light and air. Odor: aromatic especially
              when warmed; taste, slightly acrid.

              Solubility
                     Guaiacum resin is soluble in ether, in chloroform, in alcohol, and in solutions
              of chloral hydrate and of caustic alkali.  It is partially soluble in benzene, and in
              carbon disulfide.

              Constituents
                     Guaiacum resin consists chiefly of - and -guaiaconic acids (about 70 %),
              guairetic  acid  (about  11.25  %),  and  a  small  amount  of  guaiacic  acid.    Other




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