_Fructus Elaterii_; _Elaterium Fruit_, _Squirting Cucumber_, _Wild
Cucumber_; F. _Concombre purgatif ou sauvage_; G. _Springgurke_.
=Botanical Origin=—_Ecballium[1121] Elaterium_ A. Richard (_Momordica
Elaterium_ L.), a coarse, hispid, fleshy, decumbent plant without
tendrils, having a thick white perennial root. It is common throughout
the Mediterranean region, extending eastward as far as Southern Russia
and Persia, and westward to Portugal. It succeeds well in Central
Europe, and is cultivated to a small extent for medicinal use at
Mitcham and Hitchin in England.
=History=—Theophrastus mentions the plant under notice by the name
of Σίκυος ἄγριος. It is also particularly noticed by Dioscorides,
who explicitly describes the singular process for making elaterium
(ἐλατήριον), which was almost exactly like that followed at the present
day.
The Wild or Squirting Cucumber was well known and cultivated in gardens
in England as early as the middle of the 16th century.[1122]
[1120] _Indian Annals of Med. Science_, vi. (1859); _Pharmacopœia of
India_, 1868. 93.
[1121] _Ecballium_ from ἐκβάλλω, I expel, in allusion to the expulsion
of the seeds: often erroneously written _Ecbalium_.
[1122] Turner’s _Herball_, 1568, part i. 180.
=Description=—The fruit is ovoid-oblong, nodding, about 1½ inch long,
hispid from numerous short fleshy prickles terminating in white
elongated points. It is attached by a long scabrous peduncle, is fleshy
and green while young, becoming slightly yellowish when mature; it is
3-celled and contains numerous oblong seeds lodged in a very bitter
succulent pulp. The fruit when ripe separates suddenly from the stalk,
and at the same moment the seeds and juice are forcibly expelled
from the aperture left by the detached peduncle. This interesting
phenomenon[1123] is due to the process of exosmosis, by which the juice
of the outer part of the fruit gradually passes through the strong
contractile tissue which lines the central cavity, until the pressure
becomes so great that the cell gives way at its weakest point. This
point is that at which the peduncle is articulated with the fruit; and
it is the sudden and powerful contraction of the elastic tissue when
relieved from pressure that occasions the violent expulsion of the
contents of the central cavity.
For the preparation of the officinal elaterium, the fruit has to be
employed while still somewhat immature, for the simple reason that it
would be impossible to gather it so as to retain its all-important
juice if left till quite ripe. When it is sliced longitudinally as
in making elaterium, some of the juice is expelled by virtue of the
endosmotic action already described, as can easily be seen on examining
the contracted lining of the sliced fruit.
Pereira observes[1124] that if the juice of a fruit is received on a
plate of glass, it is seen to be nearly colourless and transparent.
In a few minutes however, by exposure to the air, it becomes slightly
turbid, and small white coagula are formed in it. By slow evaporation,
minute rhomboidal crystals make their appearance: these are _elaterin_.
Hot, dry weather favours the development of the active principle of the
drug.[1125]
=Microscopic Structure=—The middle layer of the fruit is built up of
large somewhat thick-walled cells, traversed by a few fibro-vascular
bundles. The former abound in small starch grains, and also contain
granules of albuminous matter.
=Chemical Composition=—The experiments of Clutterbuck (1819) proved
that the active properties of the elaterium plant reside chiefly,
though not exclusively, in the juice that surrounds the seeds; and it
is to this juice and to the medicinal product which it yields, that the
attention of chemists has been hitherto directed.
The juice obtained by lightly pressing the sliced fruits is at first
greenish and slightly turbid. After having been set aside a few hours,
it yields a deposit, which has to be collected on calico, rapidly
drained with gentle pressure between layers of bibulous paper and
porous bricks, and dried in a warm place. The substance thus obtained
is the _Elaterium_ of pharmacy.[1126] The method recommended by
Clutterbuck[1127] involves no pressing. The juice of the sliced fruit
is saved, and the pulp, scooped out by the thumb of the operator, is
thrown on a sieve and slightly washed with pure water. From these
liquors, elaterium is deposited.
[1123] I have not yet seen Yule’s paper on the dehiscence of this fruit
in the _Journ. of Anat. and Physiology_, 1877. The structure of the
testa of the seed is explained by Fickel, in the _Botanische Zeitung_,
1876. 774.—F. A. F..
[1124] _Elem. of Mat. Med._ ii. (1853) 1745.
[1125] Having had to procure elaterium fruits at Mitcham in the very
fine summer of 1868, I was told that the people occupied in slicing
the fruits had never suffered so severely from their work as in that
year.—D. H.
[1126] There is a genus of _Cucurbitaceæ_ founded by Linnæus, also
called _Elaterium_.
[1127] _Lond. Med. Repository_, xii. (1820) 1.
Elaterium occurs in irregular cake-like fragments, light, friable, and
opaque; when new, of a bright pale green, becoming by age greyish and
exhibiting minute crystals on the surface. It has a herby tea-like
odour and a very bitter taste. The produce is extremely small: 240 lb.
of fruit gathered at Mitcham, 1Oth August 1868, yielded 4⅝ ounces of
elaterium = 0·123 per cent.
Elaterium consists, according to Pereira, of _Elaterin_, to which the
activity of the drug is due, contaminated with green colouring matter,
cellular tissue, and starch, together with a little of the residue of
the bitter liquor from which these substances were deposited. Yet, in
our opinion, this description is not applicable to the best varieties
of elaterium. We have examined elaterium carefully prepared in the
laboratory of Messrs. Allen and Hanburys, London, and a fine specimen
imported from Malta. Both are devoid of starch, as well as of cellular
tissue, but were seen to be largely made up of crystals. The first
sample contained 12 per cent. of water, and yielded after drying, 8·4
per cent. of ash.
The most interesting principle of elaterium is _Elaterin_, C₂₀H₂₈O₅,
discovered about the year 1831 by Morries, and independently by
Hennell. The best method of obtaining it, according to our experience,
is to exhaust elaterium with chloroform. From this solution, a white
crystalline deposit of elaterin is immediately separated by addition
of ether. It should be washed with a little ether, and recrystallized
from chloroform. We have thus obtained 33·6 per cent. of pure elaterin
from the above-mentioned elaterium of London, and 27·6 per cent. from
that of Malta. Elaterin crystallizes in hexagonal scales or prisms; it
has an extremely bitter, somewhat acrid taste. It is readily soluble in
boiling alcohol, amylic alcohol, bisulphide of carbon, or chloroform.
Its alcoholic solutions are neutral and are not precipitated by tannin,
nor by any metallic solution. It is but very little coloured by cold
concentrated sulphuric acid.
Elaterin is the drastic principle of _Ecballium_; if to its boiling
alcoholic solution, solid caustic potash is added, the liquid thus
obtained is stated by Buchheim (1872) to be no longer precipitable by
water. The elaterin is then in fact converted into an acid body, which
may be separated by supersaturating the solution with a mineral acid.
The principle thus obtained has been found by Buchheim to be devoid of
drastic power.
The fresh juice of the fruits was found by Köhler (1869) to contain
95 per cent. of water, 3 to 3·5 of organic and 1 to 1·6 of inorganic
constituents. The same chemist observed that the percentage of elaterin
gradually diminished as the season advanced, until in the month of
September he was unable to obtain any of it whatever.
Walz (1859) found in the juice of the fruits and herb of _Ecballium_,
as well as in that of _Cucumis Prophetarum_ L., a second crystallizable
bitter principle, _Prophetin_, and the amorphous substances _Ecballin_
or _Elateric Acid_, _Hydro-elaterin_, and _Elateride_, all of which
require further examination.[1128] Prophetin is a glucoside,—not so
the other principles. The four together constitute, according to Walz,
8·7 per cent. of elaterium, which moreover contains about the same
percentage of pectic matter.
[1128] Gmelin’s _Chemistry_, xvii. (1866) 335-367.
=Uses=—Squirting cucumbers are only employed for making elaterium,
which is a very powerful hydragogue cathartic.[1129] Elaterin is not
employed in medicine, but seeing how much elaterium is liable to vary
from climate or season, it might probably be introduced into use with
advantage.