Angelica Root (Du Huo)
When you hear that name of Angelica root, the angelica archangelica, or better known as garden angelica, angelique, archangel, must be the first one that comes to you mind, mustn’t it? However, you might not know the fact that there are quite a few different species in the genus called Angelica. Likewise, many other members in this genus, such as angelica pubescens (Du Huo), Angelica Dahurica (Bai Zhi), and Angelica sinensis (dang gui), are also high-value pharmaceutical herbs. But this article is all about the Angelica pubescens root and the following Angelica root will refer to this herb if the species is not specified.
What is Angelica root?
As previously mentioned, Angelica, a genus in the family Apiaceae, covers somewhere around 60 different species, among which Angelica pubescens, also known as shishiudo in Japanese common name, is one of its members. And in TCM (Traditional Chinese medicine) it mainly means the dried root of Angelica pubescens Maxim. f. biserrata Shan et Yuan. Its harvest time is in early spring when seedlings are just sprouting or in late fall after stems and leaves withered. Next it needs to remove the fibrous roots and dirt before half drying them. And then stack them for 2 to 3 days till they become soft. Finally dry them completely by the fire.
The root is slightly cylindrical, 10 to 30cm long, and with 2 to 3 or more branches in the lower part. Root head is dilated, coniform, 1.5 to 3cm in diameter and with residue or depression left by stems and leaves on top. The taupe or brown surface is with longitudinal wrinkles, long ridgy horizontal lenticels, and slightly protruding marks of radicula. It is hard but becomes soft when affected with damp. Cortex is gray and with majority scattered brown oil cavity. Xylem is from greyish yellow to yellow-brown and forms brown ring levels. It has a peculiar aroma and bitter, acrid taste, which tends to cause a numb feeling and tingling in the lips and tongue.
Main chemical constituents include furanocoumarins, columbianetin, columbianetin acetate, osthol, isoimperatorin, bergapten, xanthotoxin, columbia-nadin, columbianetin-β-D-glcopy-ra-noside, anpubesol, angelol D, G, B, γ-aminobutyric acid, and volatile oil. And volatile oil contains more than 50 ingredients, mainly including eremophilene, thymol, α-cedrene, humulene, p-cresol, β-cedrene, humulene, p-cresol, β-cedrene, oxocy-clohexandecan-2-one, bicycol[7, 2, 0]undec-4, 11, 11-gtimethyl-8-methylene, dodecylisopropylether, 4, 4-methylenebis(2, 3, 5, 6-te-tramethyl)phenol, α-longipinene, sylvestrene, α-longipinene, nerolidol, p-cymene, α-phel-ladrene, and so on.
Angelica root benefits
Angelica root herb is one of common Chinese herbs and widely used in herbal remedies simply because it has plenty of root health benefits. It can be used by essential oil, tea, powder, tincture, capsules, extract, and so on. And its modern pharmacology can justify its popularity.
Modern pharmacological actions
1. It has anti-inflammatory, analgesic and sedative effect;
2. It has inhibition to platelet aggregation;
3. It has hypotensive effect, which however is not stable;
4. It contains bergapten, xanthotoxin and other ingredients, which has photosensitization and anti-tumor effect.
Proven angelica pubescens root related herbal remedies
Chinese herbology classifies this herb as bitter and acrid in taste and slightly warm in properties. And it covers kidney and bladder meridians. Its key functions are dispelling wind and eliminating dampness and eliminating cold to stop pain. Main Angelica root uses and indications include wind-cold-wetness type of arthralgia, waist and knee pain, headache, toothache, and more. Recommended dosage is from 3 to 10 grams in decoction.
Potential Angelica root side effects and contraindications
Xanthotoxin, by intramuscular injection, showed a median lethal dose (LD50) of 160mg/kg in rats and bergapten showed 945mg/kg. Xanthotoxin at the dose of 400mg/kg killed guinea pig by adrenal hemorrhage; at 200-300mg/kg leaded to hepatomegaly, fatty degeneration, and acute hemorrhagic necrosis, severe kidney congestion, and hematuria; at 1-2mg/kg for five consecutive months caused liver necrosis in immature rats. In addition, it was reported that there was one poisoning case of treating bronchitis with Angelica root decoction. The poisoning symptoms included dizziness, headache, tongue tingling, nausea, vomiting, stomach discomfort and other side effects. However, generally stopping medication is not necessary. And Chinese herbalist believes that Angelica pubescens root should be used with care in the case of yin deficiency with blood dryness.