Pyrus.—Apple Tree.
Preparation: Ferrated Extract of Apples
The bark of Pyrus malus.
Nat. Ord.—Rosaceae.
COMMON NAME: Common apple tree.
Botanical Source.—This is a well-known tree, growing from 20 to 40 feet high, with rigid, crooked, spreading branches, and a rough, blackish bark. The leaves are from 2 to 3 inches long, about ⅔ as wide, ovate, or oblong-ovate, serrate, acute, or short-acuminate, pubescent above, tomentose beneath, and on petioles from ½ to 1 inch in length. The flowers are large, fragrant, expanding with the leaves, of pale-rose color, and borne in subumbellate corymbs. The calyx-tube is urn-shaped, with limb 5-cleft; the pedicels and calyx villose-tomentose. Petals 5, roundish, or obovate, with short claws. Stamens numerous; styles 5, united, and villose at base. Fruit or pome globose (W.).
History and Chemical Composition.—The apple tree is a native of Europe, naturalized in this country, and flowers from April to June. There are, probably, nearly 1000 varieties cultivated in the United States, and all of which are said to be derived from the Wild crab (Pyrus coronaria, Linné). From the fruit cider is manufactured, and both the fruit and its cider are much used for domestic and medicinal purposes. The percentage composition of non-dried apples, according to the average of 36 analyses communicated by J. König (Chemie der Menschl. Nahrungs und Genussmittel, 3d ed., 1893) is as follows: Water (84.79), nitrogenous matter (0.36), free acid (chiefly in ripe fruits; malic acid, 0.82), sugar (invert sugar, with notable amounts of cane sugar, 7.22), nitrogen-free matter (starch, gum, pectin matter, 5.81), woody fiber and seeds (1.51), ash (0.49). Apples are used in the preparation of Extractum Ferri Pomatum and Tinctura Ferri Pomata, which are official in the German Pharmacopoeia. The bark of the apple tree is bitter, and has also been employed in medicine. It contains a principle called phloridzin. The root bark is the most active, and yields its virtues to boiling water. Rochleder obtained a yellow coloring matter, which he named quercetin. The leaves, according to Rochleder, contain a well-crystallizable body, isomeric with phloridzin, called isophloridzin. The seeds contain amygdalin (about 0.6 per cent).
Phloridzin, phlorizin, or phloridzite (C21H24O10.2H2O), was discovered, in 1835, by De Koninck and Stas. It is a bitter glucosid which exists in the bark of the trunk and roots of the apple, pear, cherry, and plum trees. The fresh root-bark of the apple tree contains about 3 to 5 per cent, the leaves about 0.8 per cent of this principle, while the dry root-bark does not contain it. To prepare it, the fresh bark of the root of the apple tree is boiled for 2 hours in a quantity of water sufficient to cover it. This water is decanted off, and the boiling repeated with a second portion. This last decoction must be kept separate from the first. It commonly deposits in 24 hours a considerable quantity of granular crystals of phloridzin, which, when dissolved in distilled water and treated with animal charcoal, are rendered quite pure. Another process is to digest the fresh bark of the root in weak alcohol at about the temperature of 50° C. (122° F.), continuing the digestion for 8 or 10 hours. The greater part of the alcohol is then distilled off, and the residue set aside to crystallize. Purify as in the other process.
Phloridzin forms small, white, silky needles, has a bitter taste, followed by sweetishness, is soluble in 1000 parts of cold water, but at temperatures from 24.4° to 100° C. (76° to 212° F.), it dissolves in all proportions. It is very soluble in absolute alcohol, but little soluble in ether, has a neutral reaction, and a specific gravity of 1.4298. Its alcoholic solution is optically laevo-rotatory. At 100° C. (212° F.), it loses its water of crystallization, which is not absorbed again even in a moist atmosphere. It melts at about 107° C. (224.6° F.), solidifying upon further heating at 130° C. (266° F.), and melting again at 160° C. (320° F.). Its aqueous solution is precipitated by basic acetate of lead. Boiling with diluted mineral acids converts it into dextrose and crystallizable phloretin (C15H14O5), hardly soluble in water and ether, easily soluble in alcohol and alkalies. Boiling with concentrated alkali converts it into phloroglucin (C6H3[OH]3) and phloretic acid (C9H10O3). (For further details, see Husemann and Hilger, in Pflanzenstoffe, 1884, p. 1001.)
Action, Medical Uses, and Dosage.—Apple tree bark is tonic and febrifuge, and a decoction of it has been used with advantage in intermittent, remittent, and bilious fevers, and in convalescence from exhausting diseases. It may be given in doses of 1 to 4 fluid ounces, 3 times a day. A strong decoction or syrup of the sweet apple tree bark has been employed with success in some cases of gravel. The fruit, or apple, contains both malic and acetic acids, has a pleasant and refreshing flavor, and is a useful and healthy article of diet. However, it should not generally be eaten by dyspeptics or patients afflicted with gout, rheumatism, renal, and cutaneous diseases. If indications for an acid are present, however, it is not especially contraindicated by rheumatism and dyspepsia. When baked, stewed, or roasted, it becomes valuable as an agreeable and healthy diet in febrile diseases, exanthemata, etc., and is more easily digested than when raw; it is also slightly laxative, and is beneficial in cases of habitual constipation. Raw apples should always be well masticated before being swallowed, as otherwise, they may become a source of serious difficulties, especially with children. An apple tea may be made for fever patients, by boiling a tart apple in ½ pint of water, and sweetening with sugar.
Cider forms not only a refreshing and agreeable drink for patients with fever, but actually exerts a salutary medicinal influence, especially where the tongue is coated deep-red, brown, or black. I have used cider, in which horseradish has been steeped, as an efficient remedy in dropsy, for many years; and it is now used in the preparation of a valuable agent for this disease, the Compound Infusion of Parsley. Cooked apples form an excellent local application in ophthalmic inflammation, erysipelatous inflammations, sore and swelled throat in scarlatina, ulcers, etc. (J. King).
Phloridzin is tonic and antiperiodic, and has cured cases of intermittent fever, even where quinine has proved ineffectual; its dose is from 5 to 20 grains. Unlike quinine, it does not cause gastralgia.
Related Species.—Crataegus oxyacantha, Linné (Nat. Ord.—Rosaceae), Haw, Hawthorn, English hawthorn. The fruit and bark of this shrub, or small tree, have been introduced into medicine as a heart remedy. The shrub grows abundantly in woods and thickets throughout Europe, central and northern Asia. In England it is cultivated for hedging purposes, and is familiarly known as Hawthorn. The fresh bark of the young branches contains a bitter crystallizable principle, soluble in water, insoluble in ether, little soluble in alcohol. Claims are made for this drug as a curative remedy for organic and functional heart disorders, including cardiac hypertrophy, with mitral regurgitation from valvular insufficiency, and angina pectoris. Sometimes spinal hyperemia is associated with the latter, when both are said to be relieved by the drug. The drug should be studied with a view to its adaptability to cases "characterized by pain, praecordial oppression, dyspnoea, rapid and feeble heart-action, evidence of cardiac hypertrophy, valvular insufficiency, and marked anemia" (Ec. Med. Jour., 1898, p. 176). Prof. J. A. Jeançon, M. D., employs it for venous stasis. The dose is from 1 to 20 drops, 3 or 4 times a day.