Dan dou chi (glycine max, seed / prepared soybean) releases the exterior and eliminates irritability. It is used for headache with mild heat or cold as part of the common cold, post-febrile irritability, stifling sensation in the chest and insomnia.
History
First mentioned in the Ben Cao Hui Yao (Treasury of Words on the Materia Medica) by Ni Zhu Mo (1624) in the Ming dynasty. It was one of over 6oo frequently used ‘drugs’ described Ni Zhu Mo to create a simplified text for practitioners following the Ben Cao Gang Mu of Li Shi-Zhen (1578).
Botanical outline
Glycine Max (soybean) is classed as an oilseed rather than a pulse by the UN Food and Agricultural Organization (FAO). A member of the family Fabaceae, it is an annual herbaceous plant growing to about 60cm. Alternate, ternate compound leaves, leaflets ovate and 5 to 15cms long with a 20cm long petiole. The stem and leaves are covered in coarse hairs. The flowers grow in racemes carrying from 2 to 10 flowers. It has a campaniform calyx 6mm long with 5 lobes, a papilioform corolla white, pale pink or purple 6 to 8 mm long, flowering from June to July. The legume comes in a yellowish green pos with dense yellow hair, 5-7cm long, about 1 cm wide with 2 to 4 seeds. The seeds are 6 to 9 mm long with a yellow, green or black seed coat, fruiting from July to September.It is native to the north eastern areas of China but now cutivated throughout.
It is the black-skinned beans that are used in this preparation.
Medicinal properties
TCM: Using black soybeans, various other ingredients both hot and cold. are used throughout China for its preparation. Most commonly, the black bean is decocted with water, then dried till no longer sticky. The beans are transferred to another container and covered with decocted Morus alba (sang ye) and Artemesia annua (Qing hao) and fermented until yellow hyphae appear then take out and dried.
Bitter and cold, dan dou chi enters the Lung and Stomach channels. It releases the exterior and eliminates irritability. It is used for headache with mild heat or cold as part of the common cold, post-febrile irritability, stifling sensation in the chest and insomnia.