The dried saccharine exudation.
Habitat. Mediterranean Basin, Asia Minor to Spain; Sicily, France, Italy. Syn. Manna (Flowering) Ash, European Manna Tree; Fr. Manne en Larmes; Ger. Manna.
Frax'i-nus. L. for ash tree, fr. Gr.
to fence in, enclose - i. e., the wood used lor making hedges or fences, thus protecting things and places.
Or'nus. L. Wild Ash, fr. Heb. oren, Gr. mountain ash.
- i. e., the classic name for wild
Man'na. L. fr. Gr.
Heb. man, At. mann, gift (of heaven) - divinely supplied food - i. e., to the Israelites in their journey through the wilderness of Arabia.
Plant. - Small tree, 4.5-7.5 M. (15-25°) high; stem slender, bark gray, with leaf-scars on young twigs; leaves imparipinnate, 15-20 Cm. (6-8') long; leaflets 4 pairs, 2.5-5 Cm. (1-2') long, oval, acuminate, serrate, bright green, petiolate; flowers May-June, small, numerous, white, panicles, petals, 4 Mm. (J') long; fruit samara, 2.5 Cm. (1') long, 4 Mm. (1/6') broad. Exudation (manna), in irregular, more or less elongated, flattened, 3-sided pieces, yellowish-white, friable, somewhat waxy; internally nearly white, porous and crystalline in appearance; odor slight, characteristic; taste sweet, slightly bitter, faintly acrid; also in irregular masses, partly brittle or soft, resin-like fragments, yellowish-white, yellowish-gray - the latter at least, to the extent of 40 p. c. Test: 1. Heat to boiling 5 Gm. with alcohol 100 Ml. (Cc.) - filtrate on cooling rapidly deposits crystals of mannite. Solvents: hot or cold water; alcohol. Dose, 3j_8 (4-30 Gm.).
Commercial. - The manna ash was introduced into Europe, 1710, and is so graceful as to be planted often in gardens for ornament. In Sicily whole plantations are cultivated for the juice, which is obtained from trees, at least 8 years old and stem 7.5-10 Cm. (3-4") thick, by cutting through the bark to the wood with a curved knife transverse incisions, 2.5-5 Cm. (1-2') long, and 2.5 Cm. (1') apart, the first cut being nearest the ground, and another made directly above it every day during warm weather, July-August. The next year another portion of the stem is used, so continuing 10-12 seasons, when the trees, being spent, are felled and shoots allowed to spring from the stump. Manna exudes from these incisions as a clear liquid, soon concretes on the stem, or on sticks and straws placed in the incisions for the purpose, is dried upon shelves, and packed for market in tin-lined deal boxes having partitions. There are three varieties:
Fig. 305. - Fraxinus Ornus: branch showing leaves and flowers.
Fig. 306. - Fraxinus Ornus: a, flower opened; b, single-winged fruit; c, longitudinal section of same.
1. Large Flake (Manna Cannellata, Electa), obtained when juice abundant from upper incisions, giving a product less fatty, in consequence of which it dries easily in tubes or flat pieces - the very best, Manna a cannola, on sticks, straws inserted in the cuts, being unknown in our market; 2, Small Flake (Manna in tears, lachrymis), same as preceding, only smaller and often of darker shade; 3, Sorts (Tolfa, Manna Communis), in tears from lower incisions, into which leaves, etc., are placed for it to congeal upon; it is inferior, more gummy, sticky, brownish, internally whitish, less crystalline, some being scraped from trees; 4, Fat (Manna Pinguis), flows down the trunk, Oct.-Nov., fragments united by brown viscid matter, without flakes; rarely seen in market or used in medicine.
Constituents. - Mannite 60-90 p. c, Glucose, mucilage, fraxin, resin.
Mannite, C6H8(OH)6. - Obtained with boiling alcohol and recrystal-lizing from the same several times; occurs in white prisms, soluble in water (6), slightly in absolute alcohol, insoluble in ether, by oxidation gives fermentable mannitose and various acids.
Glucose. - Sometimes 16 p. c. Mucilage and Fraxin, C22H36O20, are mostly in inferior grades; to this latter are due the fluorescence of the aqueous solution and the green color seen in some manna.
Preparations. - 1. Infusum Sennoe Compositum, 12 p. c. Dose, ℥j-3 (30-90 Ml. (Cc.)).
Unoff. Prep.: Syrup, 12.5 p. c, + sugar 77.5, alcohol 6.5, water q. s. 100, dose, 3j-2 (4-8 Ml. (Cc.)).
Properties. - Laxative, demulcent, expectorant, cholagogue, may cause flatulence and colic; action slow and constringes secondarily.
Uses. - Usually given with other medicines, as senna, rhubarb, magnesium oxide, neutral salts, etc., to which it adds purgative properties, and by its sweetness disguises disagreeable taste of its associate. Useful in piles, genito-urinary irritation, constipation of pregnancy. Mostly given to children and delicate persons, to whom its sweetness appeals.
1. Fraxinus excel"sior, European Ash. - S. Europe. Produces manna identical with the official.
2. La'rix Larix (europoea), Briancon Manna (Pinaceae); Quercus Vallo'nea, Armenian Manna (Fagaceae); Alha'gi camelo'rum, Persian Manna (Papilionaceae); Eucalyptus gonioca'lyx, E. Gun'ni and E. vimina'lis (Myrtaceae); Tam'arix mannifera, Tamarisk Manna (Tama-ricaceae). All these produce sweet exudations or mannas (not met in commerce), containing melezitose, C12H22O113H2O, or melitose, C12H28O14, or some such saccharine principle. The saccharine products of some insects as Trehala, cocoon of Lavi'nus mellificus (Syria) and Lerp, upon Eucalyptus dumosa (Australia) contain trehalose sugar, and are used as manna.