CAMBOGIA.

Botanical Origin—Garcinia Morella Desrousseaux, var. β. pedicellata, a diœcious tree,[339] with handsome laurel-like foliage and small yellow flowers, found in Camboja, Siam (province of Chantibun and the islands on the east coast of the gulf of Siam), and in the southern parts of Cochin China. It was introduced about thirty years ago into Singapore where several specimens are still thriving (1873) on the estate of Dr. Jamie. The finest is now a tree of 20 feet high, with a trunk a foot in diameter, and a thick, spreading head of foliage.

G. Morella Desr.—The typical form of this tree having sessile male flowers grows in moist forests of Southern India and Ceylon, and is capable of affording good gamboge.

G. pictoria Roxb., a large tree of Southern India, produces a sort of gamboge found by Christian (1846) essentially the same as that of Siam. It has been examined more recently by Broughton (1871) who states it to be quite equal to that of G. Morella. We have also been unable to find any difference between the product of G. pictoria as sent from Ceylon and common gamboge. Garcinia pictoria moreover is thought by Sir Jos. Hooker to agree with G. Morella.

History—The Chinese had intercourse with Camboja as early as the time of the Sung dynasty (a.d. 970-1127); and a Chinese traveller who visited the latter country in 1295-97, describes gamboge and the method of obtaining it by incisions in the stem of the tree.[340] The celebrated Chinese herbal Pun-tsao, written towards the close of the 16th century, mentions gamboge (Tang-hwang) and gives a rude figure of the tree. The drug is regarded by the Chinese as poisonous, and is scarcely employed except as a pigment.

The first notice of the occurrence of gamboge in Europe is in the writings of Clusius[341] who describes a specimen brought from China by the Dutch Admiral, Jacob van Neck, and given to him in 1603, under the name of Ghittaiemou.[342] It appears that shortly after this time it began to be employed in medicine in Europe, for in 1611, Michael Reuden, a physician of Bamberg, made use of it as he stated in 1613.[343] He termed the drug a “novum gummi purgans,” or also, Gummi de Peru, the latter strange name no doubt being a corruption of the above mentioned Ghittaiemou. The appellation “gummi de Peru” is met with in pharmaceutical tariffs during the 17th and 18th centuries.

Gamboge is one of the articles of the tariff of the pharmaceutical shops of the City of Frankfort in 1612: “Gutta gemou, a strong purgative dried juice, coming from the Kingdom of Patana in the East Indies.” Patana or Patani is the most populous province of the east coast of the peninsula of Malacca. The Dutch established there a factory in 1602, and were followed in 1612 by the English. The settlement was abandoned in 1700; gamboge was probably brought there from the opposite shore of the gulf of Siam.[344]

In 1615, a considerable quantity of gamboge was offered for sale in London by the East Indian Company. The entry respecting it in the Court Minute Books of the company under date October 13, 1615, is to this effect:—Three chests, one rundlet, and a basket, containing 13, 14, or 15 hundredweights, more or less, of Cambogium “a drugge unknown here,”—the use of which, was much commended as a “a gentle purge,” were offered for sale at 5s. per lb., but met with no purchaser.

Jacob Bontius,[345] a Dutch physician, resident, towards 1629, in Batavia, stated that “gutta Cambodja,” as he termed the drug, came from the country of the same name; he supposed it to be derived from an Euphorbiaceous plant.

Parkinson,[346] who was an apothecary of London and wrote in 1640, speaks of this “Cambugio,” called by some Catharticum aureum, as a drug of recent importation which arrived in the form of “wreathes or roules” yellow within and without.

In the London Pharmacopœia of 1650, gamboge is called Gutta Gamba[347] or Ghitta jemou.

The mother plant of the drug was not fully examined and figured until 1864; yet in 1677 already, Hermann, a German physician residing in Ceylon, had pointed out that it was a Garcinia.[348]

Secretion—We have examined a portion of a branch two inches in diameter of the gamboge-tree,[349] and have found the yellow gum-resin to be contained chiefly in the middle layer of the bark in numerous ducts like those occurring in the roots of Inula Helenium and other roots of the same natural order. A little is also secreted in the dotted vessels of the outermost layer of the wood, and in the pith. The wood, which is white, acquires a bright yellow tint when exposed to the vapour of ammonia or to alkaline solutions.

Production—At the commencement of the rainy season the gamboge-collectors start for the forest in search of the trees which in some localities are plentiful. Having found one of the full size they make a spiral incision in the bark round half the circumference of the trunk, and place a joint of bamboo to receive the sap which slowly exudes for several months. When it first issues from the tree, it is a yellowish fluid, which after passing through a viscid state hardens into the gamboge of commerce. >

The trees grow both in the valleys and on the mountains and will yield on an average in one season enough to fill three joints of bamboo 20 inches in length by 1½ inches in diameter. The tree appears to suffer no injury provided the tapping is not more frequent than every other year.[350]

According to Dr. Jamie of Singapore, the gamboge-tree grows most luxuriantly in the dense jungles. The best time for collecting is from February to March or April. The trees, the larger the better, are wounded by a parang or chopping-knife, in various parts of the trunk and large branches, when prepared bamboos are inserted between the root and the bark of the trees. The bamboo cylinders being tied or inserted, are examined daily till filled, which generally takes from 15 to 30 days. Then the bamboos are taken to a fire, over which they are gradually rotated till the water in the gum-resin is evaporated and it gets sufficiently hard to allow of the bamboo being torn off.[351]

Description—The drug arrives in the form of sticks or cylinders 1 to 2½ inches in diameter, and 4 to 8 inches in length, striated lengthwise with impressions from the inside of the bamboo. Often the sticks are agglutinated, or folded, or the drug is in compressed or in shapeless masses. It is when good of a rich brownish orange tint, dense and homogeneous, breaking easily with a conchoidal fracture, scarcely translucent even in thin splinters. Touched with water it instantly forms a yellow emulsion. Triturated in a mortar it affords a brilliant yellow powder, slightly odorous. Gamboge has a disagreeable acrid taste.

Much of the gamboge shipped to Europe is of inferior quality, being of a brownish hue or exhibiting when broken a rough, granular, bubbly surface. Sometimes it arrives imperfectly dried and still soft.

Chemical Composition—Gamboge consists of a mixture of resin with 15 to 20 per cent. of gum. The resin dissolves easily in alcohol, forming a clear liquid of fine yellowish-red hue, and not decidedly acid reaction. It forms darker-coloured solutions with ammonia or the fixed alkalis, and a copious precipitate with basic acetate of lead. Perchloride of iron colours a solution of the resin deep blackish brown.

By fusing purified gamboge resin with potash, Hlasiwetz and Barth (1866) obtained acetic acid and other acids of the same series, together with phloroglucin, C₆H₃(OH)₃, pyrotartaric acid, C₅H₈O₄, and isuvitinic acid, C₆H₃CH₃(COOH)₂.

The gum which we obtained to the extent of 15·8 per cent. by completely exhausting gamboge with alcohol and ether, was found readily soluble in water. The solution does not redden litmus, and is not precipitated by neutral acetate of lead, nor by perchloride of iron, nor by silicate or biborate of sodium. It is therefore not identical with gum arabic.

Commerce—The drug finds its way to Europe from Camboja by Singapore, Bangkok, or Saigon. In 1877 the first place exported 240 peculs, Bangkok in 1875 no less than 346 peculs, value 48,835 dollars; from Saigon there have of late been shipped from 30 to 40 peculs annually (one pecul = 133·3 lbs. = 60·479 kilogrammes).[352]

Uses—Gamboge is a drastic purgative, seldom administered except in combination with other substances.

Adulteration—The Cambojans adulterate gamboge with rice flour, sand, or the pulverized bark of the tree,[353] which substances may be easily detected in the residue left after exhausting the drug successively by spirit of wine and cold water.

Other Sources of Gamboge—Although the gamboge of European commerce appears to be exclusively derived from the form of the plant named at the head of this article, Garcinia travancorica Beddome, is capable of yielding a similar drug which may be collected to some small extent for local use, but not for exportation. It is a beautiful tree of the southern forests of Travancore and the Tinnevelly Ghats (3,000 to 4,500 feet). According to its discoverer Lieut. Beddome,[354] it yields an abundance of bright yellow gamboge.

OLEUM GARCINIÆ.

Concrete Oil of Mangosteen, Kokum Butter.

Botanical Origin.—Garcinia indica Choisy (G. purpurea Roxb. Brindonia indica Dup. Th.), an elegant tree with drooping branches and dark green leaves.[355] It bears a smooth round fruit the size of a small apple, containing an acid purple pulp in which are lodged as many as 8 seeds. The tree is a native of the coast region of Western India known as the Concan, lying between Daman and Goa.

History—The fruit is mentioned by Garcia d’Orta(1563) as known to the Portuguese of Goa by the name of Brindones. He states that it has a pleasant taste though very sour, and that it is used in dyeing; and further that the peel serves to make a sort of vinegar. Several succeeding authors (as Bauhin and Ray) have contented themselves with repeating this account.

As to the fruit yielding a fatty oil, we find no reference to such fact till about the year 1830, when it was stated in an Indian newspaper[356] that an oil of the seeds is well known at Goa and often used to adulterate ghee (liquid butter). It was afterwards pointed out as the result of some experiments that the oil was of an agreeable bland taste and well adapted for use in pharmacy. A short article on Kokum Butter was published by Pereira[357] in 1851. With the view of bringing the substance into use for pharmaceutical preparations in India, it has been introduced into the Pharmacopœia of India of 1868.

Preparation—The seeds are reniform, somewhat crescent-shaped or oblong, laterally compressed and wrinkled, ⁶/₁₀ to ⁸/₁₀ of an inch long by about ⁴/₁₀ broad. Each seed weighs on an average about eight grains. The thick cotyledons, which are inseparable,[358] have a mild oily taste. Examination under the microscope shows them to be built up of large reticulated cells containing a considerable proportion of crystalline fat readily soluble in benzol. In addition globular masses of albuminous matter occur which with iodine assume a brownish yellow hue. With perchloride of iron the walls strike a greenish-black.

The process followed by the natives of India (by whom alone the oil is prepared) has been thus described:—The seeds having been dried by exposure for some days to the sun are bruised, and boiled in water. The oil collects on the surface, and concretes when cool into a cake which requires to be purified by melting and straining.

Description—Kokum Butter is found in the Indian bazaars in the form of egg-shaped or oblong lumps about 4 inches long by 2 inches in diameter, and weighing about a quarter of a pound. It is a whitish substance, at ordinary temperatures, firm, dry, and friable, yet greasy to the touch. Scrapings (which are even pulverulent) when examined in glycerin under the microscope show it to be thoroughly crystalline. They have a mild oily taste, yet redden litmus if moistened with alcohol.

By filtration in a steam-bath, kokum butter is obtained perfectly transparent and of a light straw-colour, concentrating again at 27·5° C. into a white crystalline mass: some crystals appear even at 30°. Melted in a narrow tube, cooled and then warmed in a water bath, the fat begins to melt at 42·5 C., and fuses entirely at 45°. The residue left after filtration of the crude fat is inconsiderable, and consists chiefly of brown tannic matters soluble in spirit of wine.

When kokum butter is long kept it acquires an unpleasant rancid smell and brownish hue, and an efflorescence of shining tufted crystals appears on the surface of the mass.

Chemical Composition—Purified kokum butter boiled with caustic soda yields a fine hard soap which, when decomposed with sulphuric acid, affords a crystalline cake of fatty acids weighing as much as the original fat. The acids were again combined with soda and the soap having been decomposed, they were dissolved in alcohol of about 94 per cent. By slow cooling and evaporation crystals were first formed which, when perfectly dried, melted at 69·5° C.: they are consequently Stearic Acid. A less considerable amount of crystals which separated subsequently had a fusing point of 55°, and may be referred to Myristic Acid.

A portion of the crude fat was heated with oxide of lead and water, and the plumbic compound dried and exhausted with ether, which after evaporation left a very small amount of liquid oil, which we refer to Oleic Acid.

Finally the sulphuric acid used at the outset of the experiments was saturated and examined in the usual manner for volatile fatty acids (butyric, valerianic, &c.) but with negative results.

The fat of the seeds of G. indica was extracted by ether and examined chemically in 1857 by J. Bouis and d’Oliveira Pimentel.[359] It was obtained to the extent of 30 per cent., was found to fuse at 40° C. and to consist chiefly of stearin (tristearin). The seeds yielded 1·72 per cent. of nitrogen. Their residue after exhaustion by ether afforded to alkaline solutions or alcohol a fine red colour.

Uses—The results of the experiments above-noted show that kokum butter is well suited for some pharmaceutical preparations. It might also be advantageously employed in candle-making, as it yields stearic acid more easily and in a purer state than tallow and most other fats. But that it is possible to obtain it in quantities sufficiently large for important industrial uses, appears to us very problematical.