Galla, B.P. Galls.
Galls (Nutgall, U.S.P.) are excrescences on the twigs of the dyer's oak, Quercus infectoria, Olivier (N.O. Cupuliferae), a small tree indigenous to Asia Minor and Persia. They are formed as the result of irritation induced by the deposition of eggs by the gall-wasp, Cynips Gallae tinctoriae,Olivier (Order Hymenoptera). The nature of galls varies considerably, according to the exciting cause and the plant or part of the plant affected, but the official galls may be regarded as metamorphosed shoots, the metamorphosis being induced by the gall-wasp. This insect, of which the female only is known, introduces its eggs between the rudimentary leaves near the growing point of a shoot by means of its ovipositor. The young larvae feed upon the tissues of the plant, and secrete in the mouth a fluid which stimulates the cells of the tissues to a rapid division, resulting in the formation of galls. Within these galls the larvae pass through the pupa stage, and the wasps, as soon as they emerge, escape by piercing holes with their mandibles. The galls, collected before the perforation has been effected, are of a dark olive-green colour (blue galls), whilst those collected after perforation have a more or less pronounced yellowish or brown colour (white galls), the latter being the less esteemed. The galls are collected in Asia Minor and Persia and exported largely from Aleppo and the Persian Gulf. They are nearly spherical in shape, about 12 to 18 millimetres in diameter, and of a dark bluish-green or olive-green colour. Near the base they are smooth, but the upper portion is tuberculated. They are hard and heavy, internally yellowish or pale brown, with a small central cavity which, in unperforated galls, contains the remains of the insect; they are odourless, but have an intensely astringent taste. Below the epidermis is a parenchymatous tissue differentiated into three layers. The cells of the outer layer have thick walls and contain fragments of tannin; those of the middle layer have thinner walls and exhibit intercellular spaces, and also contain tannin. The cells of the inner layer have thin walls, are axially elongated, and firmly adherent to one another; they contain tannin and cluster-crystals of calcium oxalate. This tissue passes into a ring of irregularly pitted, sclerenchymatous cells containing small rounded starch grains with stellate hilum. The powder is well characterised by the abundance of tannin, the sclerenchymatous cells and characteristic starch grains. White galls are slightly larger than the blue galls, lighter in weight, and are less esteemed, although analysis of them does not indicate an appreciably smaller quantity of gallo-tannic acid. English galls or oak galls are smooth, globular, brown in colour, and usually perforated; they are much less active than the Aleppo, containing only 15 to 20 per cent. of gallo-tannic acid. Chinese galls, produced by a species of Aphis on Rhus semialata, Murray (N.O. Anacardiaceae), are used commercially chiefly for the manufacture of tannic acid, ink, etc. They are irregular in form, with a covering of thick, grey, velvety down, which masks their reddish-brown colour. They contain about 70 per cent. of gallo-tannic acid.
Constituents.—The principal constituent of galls is gallotannic acid, of which they contain 50 to 70 per cent. Small quantities of gallic acid (2 to 4 per cent.), ellagic acid, sugar, starch, inorganic matter (about 2 per cent.), moisture (10 per cent.), and a monobasic oxycarboxylic acid termed cyclogallipharic acid, are also present.
Action and Uses.—Galls are powerfully astringent, owing to the large proportion of gallotannic acid they contain. Tinctura Gallae is sometimes administered as an astringent, but preparations. of galls are usually applied externally. As a lotion or injection to lessen mucous discharges of the vagina or urethra, also to arrest haemorrhage from the nose or gums, Decoctum Gallae is suitable. Unguentum Gallae and Unguentum Gallae cum Opio are valuable astringents for use in painful haemorrhoids. For similar use, suppositories are prepared containing 3 decigrams (5 grains) of powdered galls with or without 6 centigrams (1 grain) of powdered opium, or 3 centigrams (½ grain) of cocaine. It should be remembered that the opium has no peripheral action; its whole benefit results from its action on the central nervous system after absorption. Preparations of galls are incompatible with the salts of iron, lead, copper, or silver.
Dose.—6 to 12 decigrams (10 to 20 grains).
PREPARATIONS.
- Decoctum Gallae, B.P.C.—DECOCTION OF GALLS. 1 in 16.
- Used locally in the form of lotion to arrest haemorrhage, and to lessen discharge from mucous membranes as in leucorrhoea.
- Tinctura Gallae, B.P., 1885.—TINCTURE OF GALLS.
- Galls, in No. 40 powder, 12.5; proof spirit, 100. Macerate the galls with 75 of proof spirit for forty-eight hours, transfer to a percolator, and when the fluid ceases to pass continue the percolation with the remainder of the spirit. Tincture of galls is rarely given internally. It is used diluted with water as a lotion to arrest haemorrhage and as an injection in gleet and gonorrhoea. Dose.—2 to 8 mils (½ to 2 fluid drachms).
- Tinctura Gallae, U.S.P.—TINCTURE OF NUTGALL.
- Nutgall, in No. 40 powder, 20; glycerin, to; alcohol (95 per cent.), sufficient to produce 100. Average dose.—4 mils (1 fluid drachm).
- Unguentum Gallae, B.P.—GALL OINTMENT.
- Calls, in very fine powder, 20; benzoated lard, 80. Mix the powdered galls with the benzoated lard by trituration. Gall ointment is used as an astringent for haemorrhoids.
- Unguentum Gallae, U.S.P.—NUTGALL OINTMENT.
- Nutgall, in very fine powder, 20; ointment, 80.
- Unguentum Gallae Compositum, B.P.C.—COMPOUND GALL OINTMENT.
- Extract of Opium, 4; distilled water, 16; wool fat, 10; galls, 20; soft paraffin, yellow, 50. This preparation is more readily absorbed than Unguentum Gallae cum Opio, and is more suitable for dispensing in collapsible tubes.
- Unguentum Gallic cum Opio, B.P.—GALL AND OPIUM OINTMENT.
- Gall ointment, 92.5; opium, in very fine powder, 7,5. Incorporate the powdered opium with the gall ointment by trituration. This ointment contains 7 ½ per cent. of opium. It may also be prepared by triturating 7.5 of finely powdered opium with 18.5 of finely-powdered galls, and 74 of benzoated lard. It is used similarly to Unguentum Gallae for haemorrhoids. To relieve pain, cocaine or belladonna is superior to opium, as the latter only exerts a sedative action after absorption.
