{CH₃
C₁₄H₁₀O₅ or (OH)₂C₆H₃·CO·C₆H₂ {O \.
{O /
It forms tasteless yellowish prisms, sparingly soluble in alcohol,
requiring about 5000 parts of water for solution. With alkalis it
yields intensely yellow crystallizable compounds, which, however,
are easily decomposed already by carbonic acid. Gentianin may be
sublimed if carefully heated at 250° C. By melting it with caustic
potash, acetic acid, phloroglucin, C₆H₃(OH)₃, and oxysalicylic acid,
C₆H₃(OH)₂COOH, are produced, as shown in 1875 by Hlasiwetz and
Habermann. The name of _gentianic acid_ or _gentisinic acid_ had been
applied to the oxysalicylic acid obtained by the above decomposition
before it was identified with oxysalicylic acid from other sources.
Gentian root abounds in pectin; it also contains, to the extent of 12
to 15 per cent., an uncrystallizable sugar, of which advantage is taken
in Southern Bavaria and Switzerland for the manufacture by fermentation
and distillation of a potable spirit.[1616] This use of gentian and its
consumption in medicine have led to the plant being almost extirpated
in some parts of Switzerland where it formerly abounded.
The experiments of Maisch (1876) and Ville (1877) have shown tannic
matters to be absent from the root.
=Commerce=—Gentian root finds its way into English commerce through
the German houses; and some is shipped from Marseilles. The quantity
imported into the United Kingdom in 1870 was 1100 cwt.
[1616] Th. Martius, _Pharm. Journ._ xii. (1853) 371.
=Uses=—Gentian is much used in medicine as a bitter tonic. Ground to
powder, the root is an ingredient in some of the compositions sold for
feeding cattle.
=Substitutes=—It can hardly be said that gentian is adulterated, yet
the roots of several other species possessing similar properties are
occasionally collected; of these we may name the following:—
1. _Gentiana purpurea_ L.—This species is found in Alpine meadows
of the Apennines, Savoy and Switzerland, in Transylvania, and in
South-western Norway; a variety also in Kamtchatka.[1617] The root is
frequently collected;[1618] it attains at most 18 inches in length and
a diameter of about 1 inch at the summit, from which arise 8 to 10
aerial stems, clothed below with many scaly remains of leaves. The top
of the root has thus a peculiar branched appearance, never found in
the root of _G. lutea_, with which in all other respects that of _G.
purpurea_ agrees. The latter is perhaps even more intensely bitter.
2. _G. punctata_ L.—Nearly the same description applies to this
species, which is a native of the Alps of South-Eastern France, Savoy,
the southern parts of Switzerland, extending eastward to Austria,
Hungary and Roumelia.
3. _G. pannonica_ Scop.—a plant of the mountains of Austria, unknown
in the Swiss Alps, has a root which does not attain the length or the
thickness of the root of _G. purpurea_, with which it agrees in other
respects. It is officinal in the Austrian Pharmacopœia.
4. _G. Catesbœi_ Walter (_G. Saponaria_ L.)—indigenous in the United
States. Its root, usually not exceeding 3 inches in length by ⅓ inch in
diameter, has a very thin woody column within a spongy whitish cortical
tissue and a bright yellow epidermis. This root is less bitter than the
above enumerated drugs; the same remark applies also to those European
Gentianæ which like _G. Catesbœi_ are provided with blue flowers.