Sweet, acrid and cool, Pueraria enters the Spleen and Stomach channels. It discharges exterior conditions to reduce fever and release the muscles (headache, stiff neck) ; relieves heat and generates fluids (stops thirst), expresses the rash of measles, raises the Yang and stops diarrhoea. The raw herb is used for relieving fever and the processed for alleviating diarrhoea.
History
The first known record of Pueraria lobata as a medicinal herb was in”Divine Husbandman’s Clasic of the Materia Medica” (Shen Nong Ben Cao Jing) written by an unknown author or authors in the Eastern Han dynasty (25-220CE) Li Shi-Zhen (1518-1593) included Ge gen in his ‘”Grand Materia Medica” (ben cao gang mu), saying that it stopped thirst, resolved toxicity, diseprsed exterior pathogens and expressed rashes.
In Japan, peuraria starch is used as a thickener in traditional cooking and as a folk remedy for acute colds, flu, fevers and digestive problems cooked with ginger juice, bancha tea and umeboshi plum.
Botanical outline
Pueraria is a genus with 15 species in the pea family Fabaceae. A perennial vine, Peuraria lobata is native to Asia and the Pacific. It is very fast growing and in the southern United States, where it is naturalized, it is listed as a noxious weed. It has also been placed on the Biosecurity Register in New Zealand. Its root is also fast growing, reaching up to 20kgs. The vine has ternate compound leaves 8-19cm x 6.5-18cm. The purple flowers occur as typically ‘pealike’, axiliary racemes. It has leguminous fruit, infrequently viable and usually spreads by vegetative reproduction. It is cultivated throughout China, the best thought to come from Guangdong Province.
It is collected from late autumn to early spring. It is cleaned, the outermost peel scraped off and the root cut longitudinally into slices or columns. It is sundried or baked over a low fire.
Medicinal properties
TCM: Sweet, acrid and cool, Pueraria enters the Spleen and Stomach channels. It discharges exterior conditions to reduce fever and release the muscles (headache, stiff neck) ; relieves heat and generates fluids (stops thirst), expresses the rash of measles, raises the Yang and stops diarrhoea. The raw herb is used for relieving fever and the processed for alleviating diarrhoea.
General: Chemical constituents include isoflavones including peurarin, daidzin, and sapogenin. They can cause a transient decrease in blood pressure and is being researched for use in relieving symptoms of hypertension.
See http://www.itmonline.org/articles/pueraria/pueraria.htm “Pueraria: Source of Important Isoflavones” by Subhuti Dharmananda, Ph.D., Director, Institute for Traditional Medicine, Portland, Oregon.