| Stephania tetandra | |
|---|---|
| Scientific classification | |
| Kingdom: | Plantae |
| Division: | Magnoliophyta |
| Class: | Magnoliopsida |
| Order: | Ranunculales |
| Family: | Menispermaceae |
| Genus: | Stephania |
| Species: | S. tetrandra |
| Binomial name | |
| Stephania tetrandra S. Moore |
|
Stephania tetrandra is a herbaceous perennial vine of the Menispermaceae family. It grows from a short, woody caudex, climbing to a height of around four meters. The leaves are arranged spirally on the stem, and are peltate, i.e. with the leaf petiole attached near the centre of the leaf. Its root is used medicinally.
Contents |
Stephania tetrandra is among the 50 fundamental herbs used in traditional Chinese medicine. The standard pinyin according to the Chinese [Herbal] Pharmacopia of the People's Republic of China (Chinese: 中华人民共和国药典; pinyin: Zhonghua Renmin Gongheguo Yao Dian) is: fen fang ji (Chinese: 粉防己), but it is more commonly known as Han Fang ji (Chinese: 漢防己; pinyin: hang fang ji). Other plants named fang ji (Chinese: 防己, roughly "snakebite remedy") are sometimes substituted for it. Notable among these is guan fang ji (Chinese: 廣防己; pinyin: guang fang ji), Aristolochia fanchi, whose main toxic component is aristolochic acid, a potent carcinogen and nephrotoxin.
Fen fang ji is of low toxicity (standard dose is: 4.5 to 9 g, overdose can occur at 30-100 g) and is traditionally used to dispel wind and dampness to relieve pain and to promote diuresis. It is classified as acrid, bitter and cold. The part used is the root. Stephania contains tetrandrine, a potent smooth muscle relaxant under investigation for treatment of cardiovascular problems and many forms of cancer.[1][2][3]
Guang fang ji preparations can contain toxic amounts of aristolochic acid when Aristolchia fanghi is substituted for Stephania tetrandra. Ingestion can lead to renal failure and even death; Aristolochia is used in TCM only with great caution. In May, 2000, the FDA began detaining any plants or medicines suspected of containing aristolochic acid, unless laboratory testing indicated they were negative for aristolochic acid. (Only tests which use a liquid chromatography/tandem mass spectrometry [LC/MS/MS] method with a precision better than 0.5 parts per million (PPM) are acceptable.)[4] The traditional route of ingestion of guang fang ji is via water decoction. Since aristolochic acid has low water solubility, water decoction is believed to be a much safer route than taking guang fang ji as an uncooked powder.[5]
Stephania alkaloids have curare-like action, and can selectively inhibit T-cell-dependent immune reactions. The root contains many isoquinoline alkaloids: tetradrine (0.6-0.9%), fangchinoline (0.5%), cyclanoline (0.1%) and dimethyltetrandrine iodide (muscle relaxant). The root also contains flavanoids. The main active alkaloids are: tetrandrine (12 to 23 grams/kg) and fangchinoline (0.3–3 mg/kg). Also present are: dimethyltetradine iodide, cyclanoline, menisine, menisidine, oxofangchirine, stephenanthrine, stepholidine and bisbenzylisoquinoline. [6][7] The root also contains flavanoids.
Cocculus trilobus, C. thunbergii Orbiculatus, Aristolochia fangchi, Simomenium actum (Japanese Han Fang Ji or Quinfengteng).