Chemical Properties
Burdock is a perennial or biennial herb that is native to Europe and northern Asia. It grows freely in waste places and
hedgerows. The plant grows up to 3 m (9 ft), with large, ovate, wavy leaves and round heads of purple flowers. When mature, the
leaves are alternate, triangular in outline, petiolate and dark green. The plant varies considerably in appearance, and various species
and subspecies have been described in the literature according to the size of the flower heads and the whole plant, the abundance of
the whitish cottonlike substance that is sometimes found on the involucres, or the absence of it, the length of flower stalks, etc. The
whole plant is a dull pale-green, with stem branched, rising from a biennial root. The dried root from plants of the first year’s growth
as well as the leaves and fruits (commonly, though erroneously, called seeds) are the parts used. Burdock root is consumed as a food
in parts of Asia, including China and Japan. In Japan, production of burdock is estimated at 180,000 tons/year.
Occurrence
Burdock is a perennial found in China, Europe, and the United States.
Uses
Burdock seeds are used for their hypotensive, myodepressant, and renotropic properties. Burdock roots are used for their hypoglycemic, antiseptic, toxicopectic, and antitumor actions. Burdock is used for skin disorders such as psoriasis, eczema,poisonivy, boils, and canker sores. Burdock compresses can soothe the swelling ofarthritis, rheumatism, and hemorrhoids. It is also commonly used in food, especiallyin Chinese populations (Jellin et al, 2008).
Composition
The roots contain inulin (up to 50%), tannins, volatile acids, polyphenolic acids, nonhydroxy acids, polyacetylenes
and γ-guanidino-n-butyric acid. The plant is also reported to contain lignans, including arctigenin, its glycoside arctin
and matairesinol; polyacetylenes, in the root, mainly tridecadienetetraynes and tridecatrienetriynes, with the sulfur-containing
arctic acid; amino acids, such as α-guanidino-n-butyric acid; inulin in the roots; and miscellaneous organic acids, fatty acids and
phenolic acids, including acetic, butyric, isovaleric, lauric, myristic, caffeic and chlorogenicacids. A xyloglucan polysaccharide
predominantly containing repeating-oligosaccharide units of hepta-(Glc:Xyl = 4:3), nona- (Glc:Xyl:Gal:Fuc = 4:3:1:1) and deca-
(Glc:Xyl:Gal:Fuc = 4:3:2:1) saccharides in an approximate molar ratio of 14:12:5, which are the typical structural units of dicot
xyloglucanswas, was isolated from the extract of A. lappa L1. Six compounds were isolated from the seeds of A. lappa L.* One of
them is a new lignan named neoarctin B; the other five compounds were identified as daucosterol, arctigenin, arctiin, matairesinol
and lappaol F.
Anticancer Research
Burdock is a plant that is sometimes used as a food. The root, leaf, and seeds arealso used to make medicine. It has been used to treat variety of ailments, includingdiabetes and hair loss, and it is said to kill germs and reduce fever. It is also used forhigh blood pressure and sometimes to increase the sex drive. In traditional Europeanmedicine, this herbal preparation can be comminute, powdered, made into a tincture,and used as a soft extract. A European powdered capsule contains 350 mg/capsule, and the dose for liquid extracts is 25–50 drops, 1–3 times/day. For tinctures,50 drops, 1–3 times/day, are recommended. The dry extract dose is 1 g/day(Gupta et al. 2004). As an Ayurvedic medicine, 40 mg/tablet of powered burdock isserved. Its roots are also used in therapeutic remedies (Poucheret et al. 2006).
