=NUX VOMICA.=
_Semen Nucis Vomicæ_; _Nux Vomica_; F. _Noix vomique_; G. _Brechnuss_.
=Botanical Origin=—_Strychnos Nux vomica_ L., a moderate sized tree
with short, thick, often crooked stem, and small, greenish-white,
tubular flowers ranged in terminal corymbs. It is indigenous to most
parts of India, especially the coast districts, and is found in Burmah,
Siam, Cochin China and Northern Australia.
The ovary of _S. Nux vomica_ is bilocular, but as it advances in growth
the dissepiment becomes fleshy and disappears. The fruit, which is an
indehiscent berry of the size and shape of a small orange, is filled
with a bitter, gelatinous white pulp, in which the seeds, 1 to 5 in
number, are placed vertically in an irregular manner. The epicarp forms
a thin, smooth, somewhat hard shell, which at first is greenish, but
when mature, of a rich orange-yellow. The pulp of the fruit contains
strychnine,[1591] yet it is said to be eaten in India by birds.[1592]
The wood, which is hard and durable, is very bitter.
[1591] Roxburgh’s assertion that the pulp “_seems perfectly innocent_,”
induced us to examine it chemically, which we were enabled to do
through the kindness of Dr. Thwaites, of the Royal Botanical Gardens,
Ceylon. The _inspissated pulp_ received from Dr. T., diluted with
water, formed a very consistent jelly having a slightly acid reaction
and very bitter taste. Some of it was mixed with slaked lime,
dried, and then exhausted by boiling chloroform. The liquid left on
evaporation a yellowish resinoid mass, which was warmed with acetic
acid. The colourless solution yielded a perfectly white, crystalline
residue, which was dissolved in water, and precipitated with bichromate
of potassium. The crystallized precipitate dried, and moistened with
strong sulphuric acid, exhibited the violet hue characteristic of
strychnine.
To confirm this experiment, we obtained through the obliging assistance
of Dr. Bidie of Madras, some of the white pulp taken with a spoon from
the interior of the ripe fruit, and at once immersed _per se_ in spirit
of wine. The alcoholic fluid gave abundant evidence of the presence of
strychnine.
[1592] According to Cleghorn by the hornbill (_Buceros malabaricus_);
according to Roxburgh by “many sorts of bird.” Beddome (_Flora
Sylvatica_, Madras, 1872. 243) says the pulp is quite harmless, and the
favourite food of many birds.
In Garnier, _Exploration en Indo-China_ ii. (Paris, 1873) 488, allusion
is made to a tree similar to that under notice having fruits which are
devoid of poison _before maturity_.
=History=—Nux Vomica, which was unknown to the ancients, is thought to
have been introduced into medicine by the Arabians. But the notices in
their writings which have been supposed to refer to it, are far from
clear and satisfactory. We have no evidence moreover that it was used
in India at an early period. Garcia de Orta, an observer thoroughly
acquainted with the drugs of the west coast of India in the middle of
the 16th century, is entirely silent as to nux vomica. Fleming,[1593]
writing at the beginning of the present century, remarks that nux
vomica is seldom, if ever, employed in medicine by the Hindus, but this
statement does not hold good now.
The drug was however certainly made known in Germany in the 16th
century. Valerius Cordus[1594] wrote a description of it about the year
1540, which is remarkable for its accuracy. Fuchs, Bauhin and others
noticed it as _Nux Metella_, a name taken from the _Methel_ of Avicenna
and other Arabian authors.[1595]
It was found in the English shops in the time of Parkinson (1640), who
remarks that its chief use is for poisoning dogs, cats, crows, and
ravens, and that it is rarely given as a medicine.
=Description=—Nux Vomica is the _seed_, removed from the pulp and
shell. It is disc-like, or rather irregularly orbicular, a little less
than an inch in diameter, by about a quarter of an inch in thickness,
slightly concave on the dorsal, convex on the ventral surface, or
nearly flat on either side, often furnished with a broad, thickened
margin so that the central portion of the seed appears depressed.
The outside edge is rounded or tapers into a keel-like ridge. Each
seed has on its edge a small protuberance, from which is a faintly
projecting line (raphe) passing to a central scar, which is the hilum
or umbilicus; a slight depression marks the opposite side of the seed.
The seeds are of a light greyish hue, occasionally greenish, and have a
satiny or glistening aspect, by reason of their being thickly covered
with adpressed, radiating hairs. Nux vomica is extremely compact and
horny, and has a very bitter taste.
After having been softened by digestion in water, the seed is easily
cut along its outer edge, then displaying a mass of translucent,
cartilaginous albumen, divided into two parts by a fissure in which
lies the embryo. This latter is about ³/₁₀ of an inch long, having
a pair of delicate 5-to 7-nerved, heart-shaped cotyledons, with a
club-shaped radicle, the position of which is indicated on the exterior
of the seed by the small protuberance already named.
[1593] _Catalogue of Indian Med. Plants and Drugs_, Calcutta, 1810. 37.
[1594] _Hist. Stirpium_, edited by C. Gesner, Argentorat. 1561. lib.
iv. c. 21.
[1595] Clusius and others held the opinion that the _Nux methel_ of
the Arabs was the fruit of a _Datura_, and an Indian species was
accordingly named by Linnæus _D. Metel_.
=Microscopic Structure=—The hairs of nux vomica are of remarkable
structure. They are formed as usual of the elongated cells of the
epidermis, and have their walls thickened by secondary deposits, which
are interrupted by longitudinally extended pores; they are a striking
object in polarized light. The albumen is made up of large cells,
loaded with albuminoid matters and oily drops, but devoid of starch.
In water the thick walls of this parenchyme swell up and yield some
mucilage; the cotyledons are built up of a narrow, much more delicate
tissue, traversed by small fibro-vascular bundles.
The alkaloids are not directly recognizable by the microscope; but if
very thin slices of nux vomica are kept for some length of time in
glycerin, they develop feathery crystals, doubtless consisting of these
bases.
=Chemical Composition=—The bitter taste and highly poisonous action
of nux vomica are chiefly due to the presence of _Strychnine_ and
_Brucine_. Strychnine, C₂₁H₂₂N₂O₂, was first met with in 1818 by
Pelletier and Caventou in St. Ignatius’ Beans, and immediately
afterwards in nux vomica. It crystallizes from an alcoholic solution
in large anhydrous prisms of the orthorhombic system. It requires
for solution about 6700 parts of cold or 2500 of boiling water; the
solution is of decidedly alkaline reaction, and an intensely bitter
taste which may be distinctly perceived though it contain no more than
¹/₆₀₀₀₀₀ of the alkaloid. The best solvents for strychnine are spirit
of wine or chloroform; it is but very sparingly soluble in absolute
alcohol, benzol, amylic alcohol, or ether. The alcoholic solution
deviates the ray of polarized light to the left.
Strychnine is not restricted to the fruit of the plant under notice,
but also occurs in the wood and bark.[1596] It is moreover found in
the wood of the root of _Strychnos colubrina_ L., and in the bark of
the root of _Strychnos Tieute_ Lesch., both species indigenous to the
Indian Archipelago.
The discovery of _Brucine_ was made in 1819 by the same chemists, in
nux vomica bark, then supposed to be derived from _Brucea ferruginea_
Héritier (_B. antidysenterica_ Miller), an Abyssinian shrub of the
order Simarubeæ. The presence of brucine in nux vomica and St.
Ignatius’ Bean was pointed out by them in 1824. Brucine, dried over
sulphuric acid, has the formula C₂₃H₂₆N₂O₄, but it crystallizes
from its alcoholic solution with 4 OH₂. In bitterness and poisonous
properties, as well as in rotatory power, it closely resembles
strychnine, differing however in the following particulars:—it is
soluble in about 150 parts of boiling water, melts without alteration a
little above 130° C. In common with its salts, it acquires a dark red
colour when moistened with concentrated nitric acid.
The proportion of strychnine in nux vomica appears to vary from ¼ to ½
per cent. That of brucine is variously stated to be 0·12 (Merck), 0·5
(Wittstein), 1·01 (Mayer) per cent.
A third crystallizable base, called _Igasurine_, was stated in 1853 by
Desnoix to occur in the liquors from which strychnine and brucine had
been precipitated by lime. Schützenberger’s investigations (1858) are
far from proving the existence of “igasurine.”[1597]
[1596] It is remarkable that parasitic plants of the order
_Loranthaceæ_ growing on _Strychnos Nux vomica_ acquire the poisonous
properties of the latter.—_Pharm. of India_, 1868. 108.
[1597] For further information on igasurine, consult Gmelin,
_Chemistry_, xvii. (1866) 589; Watts, _Dictionary of Chemistry_, iii.
(1865) 243; _Pharm. Journ._ xviii. (1859) 432.
In nux vomica, as well as in St. Ignatius’ Beans, the alkaloids,
according to their discoverers, are combined with _Strychnic_ or
_Igasuric Acid_; Ludwig (1873), who prepared this body from the latter
drug, describes it as a yellowish-brown amorphous mass, having a
strongly acid reaction and a sour astringent taste, and striking a
dark green with ferric salts. We have ascertained the correctness of
Ludwig’s observations.
Nux vomica dried at 100° C. yielded us when burnt with soda-lime 1·822
per cent. of nitrogen, indicating about 11·3 per cent. of protein
substances. By boiling ether, we removed from the seeds 4·14 per cent.
of fat; Meyer[1598] found it to yield butyric, capronic, caprylic,
caprinic and other acids of the series of the common fatty acids, and
also one acid richer in carbon than stearic acid. Nux vomica also
contains mucilage and sugar. The latter, which according to Rebling
(1855) exists to the extent of 6 per cent., reduces cupric oxide
without the aid of heat. When macerated in water, the seeds easily
undergo lactic fermentation, not however attended with decomposition of
the alkaloids. The stability of strychnine is remarkable, even after
ten years of contact with putrescent animal substances.
=Commerce=—Large quantities of nux vomica are brought into the London
market from British India.[1599] The export from Bombay in the year
1871-72 was 3341 cwt., all shipped to the United Kingdom.[1600] Madras
in 1869-70 exported 4805 cwt.; and Calcutta in 1865-66, 2801 cwt. The
quantity imported into the United Kingdom in 1870[1601] was 5534 cwt.
Nux vomica is stated by Garnier (_l.c._ page 429, note) to be largely
exported from Cambodja to China.
=Uses=—Tincture and extract of nux vomica, and the alkaloid strychnine,
are frequently administered as tonic remedies in a variety of disorders.