The air potato, also known as Dioscorea bulbifera in scientific name and Huang Yao Zi in Chinese name, is a common Chinese herbal medicine. The medicinal uses of this edible herb are immeasurable but one of its greatest health benefits is its ability to fight cancer. Sun Simiao，the China’s “King of Medicine”, was a great physician who could cure various incurable diseases. He ever made a famous formula containing this ingredient that mainly treated the goiter and tumor, which at that time foiled all other physicians. As a matter of fact, today this formula still remains in use clinically and becomes one of the most convenient and effective solutions for this type of disease. Read on please if you are interesting in knowing more about this amazing herb and what this formula is.
What is air potato?
Medicinally it means the tubers of Dioscorea bulbifera L., a vine plant of Asian or African origin in the family Dioscoreaceae, or true yam family. However, in many tropical areas it is in the list of invasive species and considered an unwelcome weed. Hence, other names of it are Dioscorea Bulbifera Tuber, Tuber Dioscoreae, Rhizoma Dioscoreae Bulbiferae, Airpotato Yam Rhizome, dioscoreae rhizoma, Dioscoreae bulbiferae Rhizoma, dioscorea yam, dioscorea root, radix dioscoreae, etc. In China it is mainly produced in Hubei, Hunan, Jiangsu and other places. In terms of medicinal properties, the one harvested during autumn and winter is usually considered preferred. After the harvest, remove its leaves and fibrous roots, wash clean, slice, dry in the sun, and use it raw.
This is one of the most recognizable herbaceous perennial twining vines because of the obvious aerial bulbs. Tubers are solitary, spherical or conical, 3 to 10cm in diameter, and with dark black skin and dense fibrous roots. Stems are cylindrical, up to several meters long, green or purple, and glabrous. Inside the leaf axils there are spherical or ovoid bulbils that are purple brown. Air potato leaf is alternative. Ovate blade is wide heart-shaped, 7 to 22cm long and 7 to 8cm wide, and with caudate apex, broadly cordate base and entire margin. Flowers are unisexual and dioecious. Many small flowers, yellow and white and axillary, form the spica. Capsule is drooping, oblong, and with 3 membranous wings. The flowering period is from August to September and fruit period is from September to October. Main habitats are valley, river bank, roadsides or forest edges.
Basic chemical constituents are diosbulbin A, saponins, tannins and starch. Semi-dried air potato tuber contains sucrose 22.5%, sugar 0.69%, starch 2.5%, saponins, and tannins. Also it contains diosbulbin B, C and diosgenin.
Air potato benefits
As mentioned above, Sun Simiao ever created an effective air-potato recipe for the treatment of goiter and tumor. Later, he disclosed it in his medical book. Actually this prescription and directions are quite simple. Firstly, soak 500 grams of air potato yam into 1000 ml of the rice liquor, seal the bottle, heat it for a while, and serve after it cools down. In recent years, there were clinical reports that this soaked wine was ever used for the treatments of 7 cases of thyroid adenoma, 2 cases of thyroid cancer, and 4 cases of other thyroid enlargement. Among them, 3 were ineffective but the rest cases gradually vanished by more than 50%, namely the diameter of neck reduced by up to 25%. What’s more, 6 cases eliminated the symptoms and signs by 80% or even 100%. This shows that the dioscorea bulbifera wine does live up to its fame. Modern research has found that it also works for other tumors. And now let its pharmacology tell you with more air potato facts.
Modern pharmacological actions of dioscorea bulbifera
1. It has a certain therapeutic effect on goiter caused by iodine deficiency in animals;
2. Its decoction and alcohol extract inhibits isolated intestine, excites non-pregnant uterus, and stops bleeding;
3. Water extract in vitro has different degrees of inhibition on a variety of pathogenic fungi;
4. Its decoction and alcohol extract can directly inhibit cardiac muscle. And the latter showed stronger inhibition than the former.
Selected herbal remedies on tuber dioscoreae
The Chinese Materia Medica tells that it is bitter in taste and cold and slightly poisonous in properties. And it goes to two meridians of lung and liver. Chief functions cover removing stasis to cure goiter, clearing heat and removing toxicity, and cooling blood and hemostasis. Basic uses and indications include goiter and tumor, pharyngitis, carbuncles and boils, snakebite, tumor, hematemesis, nosebleed, pertussis, and lung-heat cough and asthma. Recommended dosage is from 3 to 9 grams in decoction, soaked wine, or powder.
1. Hai Yao San. From Zheng Zhi Zhun Sheng (Standard of Diagnosis and Treatments), this recipe combines Hai Zao (Sargassum Seaweed), Mu Li (Oyster Shell), etc. to cure provoked goiter.
2. Huang Yao Tang. From Sheng Ji Zhong Lu (The Complete Record of Holy Benevolence), the formula uses it with E Jiao (Donkey-Hide Gelatin) for chronic epistaxis.
3. Huang Yao Tang. From The Complete Record of Holy Benevolence, this prescription takes it alone for recurrent hematemesis.
4. Huang Yao Zi San. From Bian Que Xin Shu (Medical Understanding of Bian Que), it uses its powder alone for the treatments of acute laryngeal infection, swollen cheek and chin, and phlegm in chest and diaphragm.
Air potato side effects and contraindications
Though modern pharmacological studies confirm that air potato tuber is with multiple therapeutic effects, its adverse reactions occurred from time to time. That’s to say, its toxicity shouldn’t be overlooked clinically when it is used for the treatment of goiter. Regardless of this herb alone or compound preparation, overdose is equally bad. The common toxic symptoms include gastrointestinal reactions like vomiting, diarrhea, abdominal pain and others. And it may also cause some certain damage to the liver and kidney, or even blood clotting disorders. TCM wise, use it with caution in the cases of deficiency of spleen and stomach, hepatic insufficiency, and renal insufficiency.