ALOE.
645
Trichinopoli Aloes. —Resembles Cape aloes in its brittleness, odour,and colour, but is more opaque. Its price is marked two annas[about threepence] a pound.
1 , These aloes are probably the produce, in part at least, of Aloe indica ,.Vie; a species with reddish flowers, common in dry situations in the\.° r . vves ^ em P rov i n ces of India , and which, if known to Roxburgh,^ as included by him in the A. perfoliata, Linn, and perhaps also ofv ulgaris, or the plant mentioned hy Rheede ( Hort . Malab. ii. t. 3,)Wle, Bot. of the Himalayan Mountains ).
^CoMPOsmoN.—Aloes has been analysed by Trommsdorf {Ann. de
io5), by Braconnot ( Journ. de Physiq. t. lxxxiv. p. 334, 1817), andy tinkler, (Geiger, Handb. d. Pharm. Bd. ii. p. 782, 1829).
l)n - t. lxviii. p. 11, 1808), by Bouillon-Lagrange and Vogel {ditto,
Trommsdorf.
Bouillon-La grangeand Vogel.
Braconnot.
Winkler.
Socotrine.
Saponaceous princip. 75
. ..... 25
r^etable albumen 0acid. trace
81*25
6*25
12*5
trace
Soc.
Extractive 68Resin .... 32Vegetable?albumen? u
Bar.
52
42
6
Soc.
Bitter princip. 73Puce do. 26Impurities .. 1
Soc.
Bitter matter 50
Resin. 50
Albumen.... 0
Bar .6035
5
. too
100-00
100
100
100
100
100
H, e ‘ Aloe sin, Pfaff, ( Saponaceous principle; Extractive; Ritter principle or matter) is^ Principal constituent of aloes. It is contained in the cold infusion of aloes,e v , also in a decoction which has cooled ; it may be obtained from either bytut i- ration - Thus procured, it is a brown and bitter mass, readily soluble in water,o t d 'fficultly so in spirit of wine. In pure alcohol or ether it is said to be insoluble,jOj ® a riy so. Besides carbon, hydrogen, and oxygen, it contains nitrogen, for it yieldsHi t /? 0t >ia by destructive distillation, and furnishes carbazotic acid when treated byOu c , a cid. Aloesin is probably a mixture or compound of various proximate principles.i ,le d as above, Braconnot says it contains some of the puce-coloured principle, which£ be removed by oxide of lead.
Us; ' Resin .—The substance which deposits from a decoction of aloes as it cools iscA) y denominated resin. Braconnot says it is a mixture of aloesin and puce-principle .- Berzelius , that it is apotheme combined with unaltered extract. Ithc e tls Parent, brown, fusible, soluble in alcohol, ether, and alkaline solutions. Thebm ' er> louredprinciple of Braconnot is an odourless and tasteless powder, combustible,tOf,, not fusible; and is prepared by digesting aloes with water and oxide of lead—a^Pound of the puce principle and the oxide is procured, which is to be washed andt’fj'bposed by weak nitric acid : the oxide is dissolved, and the puce principle left.
• felln?i, raconnot’s observations, this principle seems to be rather oxidized extractive
3 "-erne, Berz.) than resin.
W Vegetable albumen. —This term is applied to a substance insoluble in both water
4 a ‘cohol.
> Vk ^ oet * c acid, {Gallic acid, Trommsdorf.)—A solution of aloes reddens litmus,
I e "s ferruginous solutions, but does not precipitate gelatin: hence Trommsdorf
. tb r; ® e d the presence of gallic acid. But while gallic acid causes a blue colour with
^ P ers alts of iron, infusion of aloes produces an olive brown one. Furthermore, ifas °f diacetate of lead be added to the infusion, and sulphuretted hydrogen be
> Ufaj through the filtered liquor, to throw down the excess of lead, the boiled and
liquor possesses the property of becoming olive brown on the addition of scs-. t i> er ,i 0rid e of iron. Hence it appears to me that the acid is a peculiar one, and I have,
, ^°re, termed it aloetic acid. It must not be confounded with artificial aloe bitter,
t ^°es “y Braconnot aloetic acid, and which is prepared by the action of nitric acid on1 ‘ L'ebig (Poggendorf’s Annalen, xiii. 205) has shewn this to be a mixture of
3 k C . or nitrous acid, carbazotic acid, and a peculiar, non-acid, resinous red matter.
)Uh., eissner (Pfaff’s Mat. Med. vol. vii. p. 171) has given the name of Aloine to a6< ^ a lkali in aloes. Its solution was browm, and acted as an alkali dn reddenedUs Paper. With sulphuric acid, aloine formed a crystalline salt.