Lactuca virosa,


The dried milk-juice.

Habitat. C. and S. Europe, W. Siberia, naturalized in New England; cultivated.

Syn. Lactucar., Acrid Lettuce, Wild Lettuce, German Lactucarium, Strong-scented Lettuce, Prickly Lettuce, Green Endive; Fr. Laitue vireuse, Lactucarium; Ger. Giftlattichsaft.

Lac-tu'ca L. lac, lactis, milk - i. e., from the milky juice which exudes when plant is punctured or broken.

Vi-ro'sa. L. virosus, poisoning - i. e., its medicinal properties or odor opiumlike.

Lac-tu-ca'ri-um. L. lactuca, lettuce, of or belonging to lettuce.

Plant. - Biennial herb with brown tap-root; stem .6-2 M. (2-6°) high, erect, glabrous, prickly, pale glaucous-green, often purple-spotted; leaves runcinate - radical .4-.5 M. (16-18') long, obovate, entire - cauline smaller, few, sessile, spinose apex and margin; base auric-ulate, pale glaucous-green, midrib spiny beneath; flowers Aug., pale yellow, 12-25 Mm. (1/2-1';) broad, panicles. Milk-juice (lactucarium), usually in quarter sections of hemispherical masses, or irregular, angular pieces, dull reddish-brown, grayish-brown; fracture tough, waxy; internally light brown, yellowish, somewhat porous; odor distinctive, opium-like; taste bitter. Powder, brownish; microscopically - irregular fragments without cellular structure, which, mounted in hy-drated chloral T. S., become clear, showing granular fragments, and from this deposit numerous rod-shaped crystals, broad mono-clinic prisms, and aggregates of these, all polarizing light. Tests: 1. Triturate with water - turbid mixture; with boiling water - filtrate clear while hot, turbid on cooling, but clears with ammonia water or alcohol; with iodine T. S. - not colored blue (abs. of starch). 2. Alcoholic solution + a drop of ferric chloride T. S. - only a faint green color (abs. of tannin). Pulverizes more readily after drying at 70° 0. (158° F.); contains moisture 15 p. c; juice loses in drying 75 p. c.

Fig. 414.   Lactuca virosa.

Fig. 414. - Lactuca virosa.

Solvents: water dissolves 51 p. c, diluted alcohol 36-44 p. c, spirit of chloroform 55-60 p. c, being mostly lactucerin. Dose, gr. 1-8-15 (.06-.5-1 Gm.).

Commercial. - Plant, cultivated chiefly in Germany, France, Great Britain, Austria, has a disagreeable, narcotic odor, a bitter saline taste, and all parts abound in a white, milky juice that instantly exudes upon being wounded, becoming when dried official lactucarium. There are three varieties: 1, English, collected in England, Scotland when stalks become thick and succulent, and flower buds appear, Aug.-Sept., by collectors passing up the rows, cutting off the heads of each stalk, and scraping the exuding juice into small tin vessels - two scrapers following one cutter - a process repeated 6-7 times daily for several weeks, each cut being made a little lower down the stalk. By night the juice has thickened into a viscid mass when it is turned out of the vessels, divided into suitable size pieces, and dried by gentle heat for about 5 days, losing 75 p. c. in weight - the yield per plant being 3iij-4 (12-15 Gm.), of dried product 40-50 grains (2.6-3.3 Gm.); it is difficult. to powder and emulsifies only with acacia; 2, German, prepared chiefly near Zell, small town on the Moselle, by cutting the stems off, just before flowering, a foot (.3 M.) below the apex, and thereafter removing daily, May-Sept., a thin transverse slice, when the white exuding juice, soon turning brown, is scraped from the scarified top with the finger and put into earthen pots where it quickly hardens; it 'then is turned out on frames to dry in the air, and enters market in angular lumps; 3, French (Aubergiers), originally cultivated and used by Aubergier, being the milky juice of L. sagitta'ta altis-'sima) collected in glass vessels from transverse incisions made daily in the stem from above downward; upon coagulation it is shaped into circular cakes, 4 Cm. (1 3/5) thick, and dried on sieves; seldom reaches our market. Thridace is the juice of L. sativa obtained like lactucarium, or expressed from the stalks, clarified by coagulation, expressed and inspissated - Lactucarium Gallicum. Some countries prefer the dried expressed juice, or extract of fresh stalks with 65 ]). c. of alcohol, or alcoholic extract of fresh juice.

Constituents. - Lactucerin (lactucon) 50-60 p. c, Lactucin, Lac-tucic acid, Lactucopicrin, (caoutchouc, resin, sugar, oxalic, citric, and malic acids, gum, wax, asparagin, volatile oil, ash 10 p. c).

Lactucerin, C28H44O2. - Obtained from lactucarium with boiling alcohol and recrystallization; forms thin, colorless, tasteless, odorless needles, and is claimed to be the acetate of alpha- and beta-lactucerol, soluble in hot alcohol, chloroform, ether, benzin, oils.

Lactucin, C11H12O3H2O. - This gives most of the bitter taste; occurs in odorless, white pearly scales or rhombic plates, soluble in hot water, alcohol, cold water (60), insoluble in ether, turns red and then brown by alkalies, losing its bitterness, and by oxidation produces lactucopicrin. Dose, gr. 1-4 (.06-26 Gm.).

Lactucic Acid and Lactucopicrin, C44H32O21. - These are in the mother-liquor of lactucin, the former being crystalline, bitter, red with alkalies; the latter amorphous, bitter, both soluble in water, alcohol.

Preparations. - 1. Tinctura Lactucarii. Tincture of Lactucarium. (Syn., Tr. Lactucar.; Fr. Teinture de Lactucarium; Ger. Lactu-cariumtinktur.)

Manufacture: 50 p. c. Beat lactucarium 50 Gm. to a coarse powder with clean sand, to this in a bottle add purified petroleum benzin 200 Ml. (Cc.) (to remove inert resinous lactucerin, caoutchouc, etc.), cork tightly, set aside 48 hours, frequently agitating, pour mixture on double filter, drain, wash residue gradually with purified petroleum benzin 150 Ml. (Cc); when lactucarium dry and free from benzin odor from exposure, pulverize, using more sand, if necessary, pack, macerate, and percolate with glycerin 25 Ml. (Cc.), alcohol 50 Ml. (Cc.), water 25 Ml. (Cc.), continuing with diluted alcohol until exhausted, reserving the first 75 Ml. (Cc.) of percolate; evaporate remainder to 25 Ml. (Cc.) and mix it with the reserve, filter, wash filter with diluted alcohol q. s. 100 Ml. (Cc.). Dose, 3ss-l (2-4 Ml. (Cc.)).

Prep.: 1. Syrupus Lactucarii. Syrup of Lactucarium. (Syn., Syr. Lactucar.; Fr. Sirop de Lactucarium; Ger. Lactucarium-sirup.) Manufacture: 5 p. c. Mix tincture of lactucarium 10 Ml. (Cc.) with glycerin 20 Ml. (Cc.), add orange flower water 5 Ml. (Cc.) in which has previously been dissolved citric acid .1 Gm., filter, add syrup q. s. 100 Ml. (Cc.). Dose, 3j-4 (4-15 Ml. (Cc.)). Unoff. Preps.: Fluidextract, dose, ej-30 (.06-2 Ml. (Cc.)). Lozenges. Properties. - Anodyne, sedative, hypnotic, diuretic, expectorant, very unreliable, milder than opium, and, unlike it, does not derange the digestive organs.

Uses. - Where opium is objectionable, to procure sleep, allay cough, dropsy, palpitation of heart, intermittent fevers, nervousness. Allied Plants: