H^ / \> ys^ i/ y K ANALYSIS -_ A OF RHUBARB. By J. H. Salisbury, M. D. ALBANY: CHARLES VAN BENTHUYSEN, PRINTER. 1850. f A^- EXAMINATION OF RHUBARB. General remarks. — Of rhubarb, the following are the principal species and varieties in cultivation. The Rheum rhaponticum (common pie plant), a native of Asia, introduced in 1575 ; R. undulatum, a native of China, introduced into Europe in 1734 ; Elford rhubarb, or scarlet va- riety; R. hybridum, a native of Asia, cultivated in 1778; Giant rhu- barb, a variety of the rhaponticum ; R. palmatum, or Turkey rhubarb ; R. compactum and R. australe. Besides the above, there are several varieties cultivated in this coun- try, principally derived from the rhaponticum. The first five kinds are cultivated entirely for their petioles. Several attempts have been made in the western part of Europe, and in this country, to cultivate the root of the first and last three mentioned sorts, for medicinal purposes ; but without any great degree of success. I do not see, however — if the composition of the root and rest of the plant were well known, together with its habits, mode of culture, time of gathering, &c. — why success might not attend its cultivation in the United States, as well as in China and Turkey. The root of good Turkey rhubarb commands now m market from three to four dollars the pound. If it could be success- fully cultivated here, it would constitute one of our most valuable and lucrative articles of trade. Uses. — The large succulent petioles are highly esteemed for making tarts, pies, jelly, preserves, wine, &c., which resemble much those made of apples and gooseberries. The root of several species is highly es- teemed in medicine, as a cathartic, possessing mild tonic and astringent properties. Among the species used in medicine, are the R. rhaponti- cum, R. palmatum, R. compactum, and K. australe. The R. rhapon- ticum, and several varieties derived from it, are mostly cultivated in this country for their very fine flavored petioles. The root grown in the western part of Europe and the United States is less firm, and acquires much less medicinal value than the root of the same species grown in China, Turkey and Russia. The reason of this difference is not well known, but is probably owing to soil, climate, time of gathering and mode of culture. Composifion of the several parts of the plant. — In this country, the several species of rhubarb are cultivated mostly for the petioles, or leaf 4 stalks. The texture and flavor of these vary greatly with the soil, mode of culture and climate. We should naturally infer that the soil in which rhubarb thrives (from its size and rapid growth) must be richly supplied with those materials in a soluble form which are found in the various organs and tissues of the plant. It is necessary to know then, the composition of the plant before we can positively decide what kind of soil is best fitted to its growth. The following analyses were made with a view of throwing some light upon this subject. The Giant rhubarb, a very fine variety of the rhaponticum, cut June 1st. Plant in flower. Stout growth. The roots were very compact, and remarkably large. Furnished by Mr. C. N. Bement, of Albany. PERCENTAGE OF WATER, DRY MATTER AND ASH, IN THE SEVERAL PARTS OF THE PLANT. Root. Stalk. Petioles. Leaf Flowers & blades, pedit els. Percentage of water, 82.000 89.50 93.465 88.00 86.90 « dry matter, 18.000 10.50 6.535 12.00. 13.10 « 'ash, 0.925 1.13 0.940 1.53 1.32 « ashcalc.ondrymat- 5.194 10.762 14.384 12.75 10.076 The percentage of water in all parts of the plant is large, amounting to from 82 to 93 per cent. The dry matter of the several parts is richly supplied with ash. The petioles contain the greatest proportion, and the root the least. ) ■ - o •£3 -H -^ ;o -H >« OS Tf ^aoioroOQO(N d d 'o csj ro -i t>^ Tft^cTiiO— . .,0 * o :^ . o : o . "O S « o o c " a -^! fi o S P u S .skills - « c .-5.2 t ^ - ^ rt rt S rt s c-::^ « to, o rz -=3 Q W ^ M 0-3 — ^ i-i « ^ -^0g3"a,3^£ o - S c rtS- «- a '^og^.2 w « -^^"^ ^ s s ^ -d - o o "5 ii rt I' ^ ■-^ « t- 5 c 13 i2 i o « C, , _, c « -r: ^^■*J > .' *^ w C --» — C/5 ^*^ f^ ^ M) .- «. cs S w 1.^ — w o " ~ SS«c c « c 5 »- rt o .2«« £-♦* j3 a 6 The analyses have been calculated without the carbonic acid, (this is not a constituent of the plant, but is formed during the combustion,) to show the real composition of the inorganic matter which actual!}^ exists in the plant, and is necessary to its constitution. The stalk and petioles contain but a small percentage of silicic acid, while the leaves, flowers, pedicels and root contain a respectable quantity. All portions of the plant are rich in phosphates, ranging from 19 to 34 per cent, in the several parts. The root contains the most, the flowers and pedicels stand next in order, the petioles next, the leaves fourth, and the stalk contains the least. The lime ranges, in the several parts, from IJ to 6.7 per cent. ; the magnesia from one-tenth of one per cent, to 3.3 per cent. ; the potash from 5.8 to 10.8 percent. ; the soda from 26.5 to 38.75 per cent. ; and the sulphuric acid from 5 to 12 per cent. The analyses show that the ash of this plant is in a great measure made up of the phosphates and sulphates of the alkalies. These mak- ing up from 69 to 79 per cent of the entire inorganic matter of the plant. It will be seen from the above that a soil well suited to nourish and sustain vigorously the rhubarb plant, must be peculiarly rich in the phosphates and sulphates of the alkalies. Bone dust, plaster, salt and ashes afiford the inorganic bodies required by this plant. Besides these, decomposing animal and vegetable manures are also needed to warm and loosen the soil and facilitate the decomposition and conse- quently the solubility of the inorganic materials. Proximate organic analysis of the petioles. — Petioles, or leaf stalks taken from the plant the first of September : very large and succulent ; 1^ inches in diameter and 2^ feet long. A variety of the Rhaponticum. Furnished by Mr. J. Rathbone, of Kenwood. PERCENTAGE OF WATER, DRY MATTER AND ASH. Percentage of water, S7.77 " dry matter, 12.23 " ash, 2.27 « ash, calc. on the dry matter, 18.56 PROXIMATE ORGANIC ANALYSIS. With Without the water. the water. Fibre, with a little starch and chlorophyl, .' 1.265 9.894 Malic acid and extract, with a little tartaric & oxalic acids, 5.710 44.622 Dextrine, , 0.550 4.302 Fibre, 3.235 25.303 Matter separated from fibre by a weak solution of potash, gives the characteristic coior of albumen with sulphuric acid, 1.605 12.554 Albumen, 0.270 2. 1 12 Casein, 0.150 1.173 Water, 87.770 100.655 100. r } The above specimen is larger and firmer than the one examined the first of June and contains less water and a greater percentage of inor- ganic matter. The leaves contain a little oxalic and malic acids. The oxalic acid is probably in the form of binoxalate of potash and soda. The petioles or leaf stalks have a mild, pleasant acid taste. They con- tain a large quantity of malic acid with considerable oxalic and a little tartaric acid. These acids are most likely in the form of acid salts of the alkalies. The well known and highly valued medicine called rhubarb is the root of several species of Rh^um. It has been analysed by Schratrder, Brande, Hornemann, M. Ossian Henry, Schlossberger and Dopping. {Pereirah Materia Medicd^ Liebig^s Annalen, Thompson s Vegetable Chemistry J U. S. Dispensatory, <^c.) It co;itains Rhein. (Syn. Rhabarbaric acid, Rhubarb Yellow, Rheumin.) This/s a yellow granular crystalline body, somewhat analogous to chry- sophanic acid. It is extracted nearly pure from the root by hot sulphuric ether. On carefully evaporating the solution it is obtained in small crys- tals which are quite tasteless and insoluble in cold water. It imparts to concentrated sulphuric acid a beautiful carmine color ; to solutions of ammonia and potash, a fine red, and to soda and lime, a light red hue. It is soluble in ether, alcohol and acetic acid, to all of which it imparts a deep yellow color ; it is less soluble in cold nitric acid, and but slightly soluble in hydrochloric and oxalic acids, all of which it colors yellow. On boiling these latter acids, more is taken up, but is again precipitated on cooling. It is thrown down from an alkaline solution by sulphuric acid in the form of a deep yellow powder, which is nearly or quite insoluble in water. It is precipitated by the acetate of lead on stand- ing for some time. The neutral salt throws it down in the form of light yellow floes, leaving a clear solution slightly tinged with yellow. The basic salt throws it down in the form of a red floculent precipitate leav- ing a slightly turbid light red solution. Aporetin. — A resinous body of a black color, brittle, decomposed at a temperature below its point of fusion. Erythroretim C,gHg O,. A light yellow crystalline, resinous body, soluble in ether and alcohol and volatilized partially by heat with- out decomposition. It aflbrds a dull red solution with concentrated sulphuric acid, from which it is thrown down in the form of a floculent precipitate by water. PhcBorctin. C,g Hg Og. A yellowish brown powder quite insolu- ble in ether and water, but readily soluble in alcohol. With the alkalies it forms a deep red solution from which it is precipitated by the mine- ral acids. 8 Rkaponticin. A yellow, tasteless, crystalizable body, insoluble in ether, but soluble in a large excess of dilute alcohol. Besides the above the root also contains chrysophanic acid, a trace of oil or fatty matter, starch, gum, mucilage, sugar, woody fibre, pectin, tannic, gallic, oxalic, sulphuric and phosphoric acids, together with chlorine, lime, magnesia, silica, iron, potash and soda. LIBRARY OF CONGRESS nil II v\ 014 338 762 8 I LIBRARY OF CONGRESS 014 338 762 8# Conservation Resources Lig-Free® Type I Ph 8.5, Buffered