An Extract is the concentrated residue obtained by evaporating the percolate, or other exhaust, of a vegetable drug. According to the degree of evaporation, Extracts appear in two forms: the Pilular Extract, of semisolid, pasty consistency; and the Powdered Extract, consisting of fine, dry powder. Such as are capable of reliable assay have a definite percentage of alkaloidal content.

Prepare the official Extractum Belladonnae Foliorum as follows: Moisten 100 Gm. No. 40 powder, belladonna leaves with 75% alcohol; pack it firmly in the percolator; saturate it with the menstruum, providing a supernatant stratum. Macerate the powder for 48 hours; then permit percolation to proceed until the percolate equals 300 mils. Distill off the alcohol, and evaporate the residue with frequent stirring, until the substance is of a pasty consistency, being careful that at no time shall the temperature exceed 70 ° C. Mix the mass thoroughly, and then weigh it. By assay (see below), determine its alkaloidal content, calculate the total alkaloids in the prepared extract, then thoroughly mix in enough glucose to make the total product contain 1.25% of the alkaloids of belladonna leaves.

Assay. In 10 mils diluted alcohol dissolve 2 Gm. pilular extract of belladonna leaves (made above). Place the solution in a separator, adding thereto repeated rinsings of the first vessel used, utilizing for this wash 10 mils of distilled water mixed with 2 mils NH4OH. Repeatedly shake out the extract solution with chloroform; then use weak H2SO4 to extract the alkaloids from the chloroform by repeated shakings out. Place the acid washings in a separator, render the solution distinctly alkaline to litmus, using NH4OH, and again extract the alkaloids by repeated shaking out with chloroform. Now evaporate the chloroform solutions to dryness; treat the alkaloids, contained in the residue, with 5 mils of ether; evaporate to dryness; treat again with 5 mils ether, and again evaporate to dryness; then dissolve in exactly 5 mils tenth-normal H2SO4 V. S., and titrate the excess of acid with fiftieth-normal KOH V. S., using cochineal T. S. as indicator.

Each mil of titer consumed corresponds to 28.92 milligrams of the alkaloids of belladonna leaves.

Properties of your Extract of Belladonna Leaves:

Appearance ......................................................

Odor ..............................................................................................................

Color ...............................................................

Taste ...............................................................................................................

Weight of your Extract (to milligrams),.....................................................................................................................

Amount of titer used,...............................................................................................................................................................................

Total alkaloids in 2 Gm. sample,.................................................................................................................................................

Total alkaloids in your Extract,...............................................................................................................................................

Amount of glucose to be added,................................................................................................................................................

Alkaloidal content of finished Extract,...............................................................................................................................

Prepare the official Powdered Extract of Rhubarb as follows: Moisten 100 Gm. No. 40 powdered rhubarb with sufficient 80% alcohol; place it in a percolator; saturate it so a stratum of the menstruum remains above; macerate it for 48 hours. Then percolate it slowly, so as to obtain 300 mils. Distill off the alcohol, evaporate the residue, at as low a temperature as possible, to a syrupy consistency. Place this in a shallow dish, adding thereto rinsings from the still (using for this purpose 80% alcohol); stirring frequently, evaporate this mixture to dryness, being careful the temperature never exceeds 70 ° C. Weigh the dry extract; add thereto 5 Gm. magnesium oxide, and enough freshly dried starch to make the product weigh 50 Gm. Mix thoroughly, reducing the mixture to a fine powder; pass this through a No. 60 sieve, and transfer it to a tightly stoppered bottle.

Note: Appearance ........................................

Odor ..........................................................................................

Color ....................................................

Taste ...............................................................................................................

There are 25 official Extracts, the majority of which are powerful preparations. They are made on a large scale by the manufacturers of pharmaceutical supplies, the pilular extracts being extensively used in pill masses and in ointments. As they rarely appear in other form their physical properties need not be studied at this time.

Preparation

Alk. Cont. Ave.

Utility

Dose

Ext. Aconiti

2%

Cardiac depressant

0.01 Gm.

Ext. Belladonna; Foliorum

1.25%

Antispasmodic

0.015 Gm.

Ext. Cannabis

Quietant and soporific

0.01 Gm.

Ext. Cascarae Sagradae

1 to 3

Laxative

0.25 Gm.

Ext. Colocynthidis

1 to 4

Purgative

0.03 Gm.

Ext. Colocynthidis Comp.

Drastic purge

0.25 Gm.

Ext. Fellis Bovis

1 to 8

Cholagogue ( ?)

0.1 Gm.

Ext. Hydrastis

10%

Stimulant to mucosa

0.5 Gm.

Ext. Nucis Vomicae

15.5%

Spinal tonic and irritant

0.015 Gm.

Ext. Opii

20%

Narcotic and analgesic

0.03 Gm.

Ext. Rhei

1 to 2

Laxative

0.25 Gm.

Of less importance, or superfluous, are the official Extracts of Cimicifuga, Colchicum Corm, Ergot, Gelsemium, Gentian, Glycyrrhiza, Hyoscyamus, Malt, Physos-tigma, Stramonium, Sumbul, Taraxacum, and Viburnum Prunifolium.