Aloin, Barbaloin

Aloe barbadensis Miller var. chinensis Berger A. vera L. Lu Wen (Aloe) (aerial part) Aloins, barbaloin, aloe-emodin, polysaccharides 49,50,403,450,510 Laxative, stomachic, emmenagogue. 

Aloe s most important ingredients — aloin, barbaloin, and aloe-emodin — are responsible for its cathartic action (see Chapter 12). 

Aloin (= Barbaloin) (anthrone glycoside) Abeferox, A. perryi, A. vera (Liliaceae) [leaf], Frangula alnus, Frangula purshiana (Rhamnaceae) PS - eEF-2 [purgative]... 

Aloin ( barbaloin ) is an anthraquinone component found in the latex of various species of aloe used to prepare the pigment known as aloe brown. The molecule, 10-glucopyranosyl-l, 8-dihydroxy-3-(hydroxymethyl)-9(10H)-anthracenone, is built from aloe-emodin q.v. Merck Index, 1996)... 

S)-10-p-D-Glucopyranosyl-1,8-dihydroxy-3-(hydroxymethyl)anthracen-9(10H)-one trivial names aloin A, (10S)-barbaloin... 

It has been found that numerous plants contain I-C-substituted an-hydroalditols. For example, barbaloin, a major constituent of commercial aloin, is 10-(a-D-glucopyranosyl)-l,8-dihydroxy-3-(hydroxy-methyl)anthrone.45 Numerous other 1-C-substituted anhydroalditols have been isolated from a variety of plant sources by various investigators. 

N.A. Aloin isobarbaloin, aloeresin A, B, aloesin glycone, aloesone, emodin, chrysophanic acid, 1,8-dihydroxy-anthracene derivatives, barbaloin, anthaquinone glycosides.99-100 108 109 510-511 Purgative, eupeptic, and cholagogue effect. It is a laxative and cathartic. Juice from leaves used for cuts and other skin problems. 

Aloe latex is an active laxative. Its effect is due to anthraquinone glycosides, aloin A and B (formerly designated barbaloin). Glycosides are probably chemically stable in the stomach (under... 

The aloe latex or aloe juice is obtained from the yellow latex of peri cyclic cells found beneath the epidermis (Swanson, 1995). It is dried to yield a solid material called "aloe" that contains anthraquinones (Leung, 1980). The specific constituents of the latex include barbaloin, which is metabolized to the laxative aloe-emodin (Leung, 1980 Blumenthal, 1998), iso-barbaloin, chrysophanic acid (Leung, 1980), and aloin (Blumenthal, 1998). The term "aloin" also refers to a crystalline, concentrated form of the dried latex (aloe). 

While C-glycoside chemistry has recently attracted much attention, they were not invented by chemists. Many examples of C-glycosides have been isolated from nature. For example, in the structures represented in Figure 1.3.1 were isolated from Barbados aloe. These compounds, aloin A and aloin B, are collectively known as barbaloin make up the bitter and purgative principle of aloe.8-12... 

Aloin [10-glucopyranosyl-l,8-dihydroxy-3-(hydroxymethyl)-9(10/ ) thracenone9 Barbaloin] [8015-61-0, 5133-19-7, 1415-73-2] M 418.4, m 148-148.5", 148-150". Aloin forms the monohydrate as lemon yellow crystals on crystallisation from H2O (450g/1.51) which has a lower m -70-80" than the anhydrous substance. [Cahn Simonsen JC/zewz Soc 2573 1932, Hay Haynes J CAe/w c 3141 1956. ... 

Occurrence. The sugar is encountered infrequently. Cathartic-acting glycosides (aloins) such as barbaloin, isobarbaloin, nataloin, and homo-nataloin from plants of the genus Aloe A. barbadensis) yield D-arabinose 39). The glycosidic union is very resistant to hydrolysis. The sugar occurs in the furanose modification as a constituent of the polysaccharide fraction of tubercle bacilli 40). 

Aloin or Barbaloin It has purging, detoxifying and markedly antibiotic properties. 

Plants of the genus Aloe contain a reduced form of aloe-emodin as the C-glucoside of the corresponding anthrone, which is called aloin. Lemon yellow aloin is a mixture of two isomers. The major product (S)-aloin or (S)-P-D-glucopyranoside-aloe-emodin is referred to as aloin A (or barbaloin, 9-162), the (l )-isomer is aloin B (isobarbaloin). Related glycosides called aloinosides a and b contain a-L-rhamnopyranose bound by an O-glycosidic bond to the hydroxymethyl group at C-3. 

Commercial aloin is a concentrated form of aloe containing high concentrations of anthia-glycosides (mostly barbaloin). This commercial product is not pure aloin. 

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