Specification & Spread

Rhubarb roots — radices rhei
Tangutic palmate rhubarb — rheum palmatum l. Var. Tanguticum maxim.
Buckwheat family — polygonaceae
It is a powerful perennial herbaceous plant up to 1.5-2.5 m tall, with a short, thick, many-headed rhizome, from which there are extended  long spindle-shaped fleshy roots.
The stems are erect, little-branched, thick (up to 4-5 cm in diameter), bare, succulent, cylindrical, grooved and hollow inside.
The bottom sand leaves are very large, together with a petiole up to 1 m long, the petioles are fleshy, up to 30 cm long. The leaf blade in diameter is up to 75 cm, broadly ovate in outline and 5-7-palmatilobate. It has acuminate and unevenly incised blades.
The stem leaves are small, alternate, on petioles, ovate, supplied at the base with dry and membranous brown sockets.
The flowers are regular, small, inconspicuous, gathered in erect pyramidal multicolored panicles located at the ends of the stems in the axils of the upper leaves.
The perianth is regular, corolliform, sexpartite, whitish-pink or red.
The fruit is a triangular walnut 6–9 mm long, red-brown in colour, with three ribs turned into wide wings.
It blossoms in June, the fruits ripen in July.
Spreading. It is found in the wild in the mountains of Southwestern China and the adjacent regions of Central Asia, where it grows on high-grass meadows in the upper part of the forest and subalpine zones. It is cultivated in specialized farms on the Moscow experimental base of VILAR and in Kyrgyzstan.
Habitat. Mostly it grows in open areas and fertilized soil.


The rhubarb roots contain two opposite groups of substances:

  • anthracene derivatives (3.5–6%) and
  • tannins (6.7-10.6%) of the condensed group.

Anthracene derivatives are represented by at least 20 compounds from the group:
reina, aloemodin, frangulaemodine (reumemodine), chrysophanol, and physiotherapy, which are in the form of anthrones, anthranols, hetero- and diantrons (palmidines A, B, C, D, readin A, B, C, sennidine C).
In addition, in the rhubarb roots there are contained:

  • flavonoids,
  • bitter glycosides,
  • pectic substances,
  • tar,
  • starch.

Harvesting and storage of raw materials

Harvesting. Rhubarb roots from cultivated plants are dug up in early spring or autumn at the age of 4-5 years, in China – at the age of 8-12 years. By this time, the roots reach a mass of 4-9 kg. The root harvesting is done in a mechanized way; sometimes shovels are used. The roots are washed in cold water, freed from lignified and damaged parts, cut into pieces no more than 15 cm long and up to 3 cm thick, and are dried in air for several days.
In addition to the roots may be present rhizomes. But their content is small, so the raw material is called «Rhubarb roots».
Security measures. It is not allowed to dig up the roots of young plants.
Drying. It is dried in air or heat dryers at 60 °C.
Storage. It is packaged in a dry, well-ventilated area, protected from light (the raw material darkens under the influence of light).

Whole raw materials
The pieces of roots and rhizomes of various shapes up is to 15 cm long, up to 3 cm thick. The large pieces of roots are cylindrical or conical, slightly curved, with a longitudinally wrinkled surface. The pieces of rhizomes are rare, its surface is wrinkled.
The colour from the surface is dark brown, on a fracture it is yellow-brown or orange-brown. The fresh fracture is grainy, grayish, with orange or pinkish streaks («marble» figure).
The smell is peculiar. The taste is bitter and astringent.
It is from light yellow to dark brown, passing through a 0.16 mm sieve.
The smell is peculiar. The taste is bitter and astringent.
In the analysis of benignity, in addition to determining the numerical values, a purity test is carried out, the purpose of which is to exclude the presence of garden rhubarb roots (Rheum rhaponticum L.) in the raw materials, which has no medicinal value.

Properties and application

Anthracene derivatives have:

  • laxative effect and
  • increase intestinal peristalsis, tannins have:
  • astringent
  • anti-inflammatory and
  • anti-inhibitory action, resinous substances also have
  • laxative effect.

Application of rhubarb
In large doses (0.5-2 g) rhubarb roots are used as:

  • laxatives, in small doses (0.05-0.2 g) – as
  • astringent and agent
  • appetite stimulant.

The laxative effect occurs 8-10 hours after ingestion and is mainly due to anthracene derivatives, which, as a result of irritation of the mucous membrane of the large intestine, cause increased motility and faster passage of feces.
The laxative and astringent effect of rhubarb depends not only on the dose, but also on the solubility of the compounds.
The water extracts from the rhubarb roots contain more antraglycosides, and alcohol extracts are richer with tannins.

It is contradicted with :

  • kidney stones and gall bladder;
  • bleeding in the stomach, hemorrhoidal hemorrhages;
  • appendicitis;
  • peritonitis;
  • an ulcer;
  • rheumatism;
  • diabetes;
  • cholecystitis;
  • inflammation of the urogenital system;
  • gout;
  • pancreatitis.