Da Qing Ye also known as Folium Isatidis is the leaf of Isatis Indigotica, which is a biennial herb belonging to the family Cruciferae. It first appeared in <Mingyi Bie Lu> around 420-589 AD.
This plant is native to China and is now distributed in Hebei, Jiangsu, Anhui and Shaanxi provinces of China. Its roots can also be made into Chinese herbs, which is called Ban Lan Gen. Its leaves can be made into blue dyes, and its seeds can be refined into industrial oils.
Every summer and autumn, people gather the leaves of Isatis Indigotica, wash them with water, chop them, use them directly or dry them in the sun, and make them into Chinese herbs.
Da Qing Ye contain indigotin, indirubin, indole, quinazolone, salicylic acid, syringic acid, benzoic acid, o-aminobenzoic acid, palmitic acid, isatan, sterols and a small number of inorganic elements.
According to <Compendium of Materia Medica>, the medicinal property of Da Qing Ye is relatively cold, with a bitter taste. It has a certain therapeutic effect on the pathological changes of the heart and stomach meridians.
In Chinese medicine, it is often used to clear heat and remove toxin, cool blood and eliminate maculae, treat influenza, upper respiratory tract infections, Japanese encephalitis, acute infectious hepatitis, acute dysentery, enteritis, Periodontitis, and cervicitis.
There are about 50 kinds of traditional Chinese medicine prescriptions containing Da Qing Ye, such as Xiao Yin Pian, Xiao Er Ganmao Keli, and Li Dan Pian.
Health benefits of Da Qing Ye
- Anti-inflammatory and antipyretic effects.
- Inhibiting Japanese encephalovirus, mumps virus, influenza virus.
- Inhibiting the heart and dilating blood vessels.
- Inhibiting platelet aggregation and preventing atherosclerosis and thrombosis.
- Promoting bile secretion, enhancing the phagocytic capacity of leukocytes, and improving immunity.
- Reducing the damage of CCL4 to liver tissue and protecting the liver.
- Removing heat toxins, treating high fever, unconsciousness, and maculae caused by heat entering nutrient-blood.
- Relieving fever, headache, thirst, and sore throat in the early stage of warm diseases or wind-heat syndrome.
- Clearing excess-fire in heart and stomach, treating sore throat and mouth ulcers caused by the exuberance of heart and stomach fire.
- Eliminating skin redness and swelling, treating sores, carbuncles, and erysipelas.
- Inhibiting Staphylococcus aureus, Streptococcus alpha, Meningococcus, Pneumococcus, Typhoid bacillus, Escherichia coli, Diphtheria bacillus, Dysentery bacillus, Trichophyton mentagrophytes, Trichophyton tonsurans, Bacillus subtilis.
- The study found that the indirubin can selectively inhibit DNA synthesis of cancer cells and treat chronic myeloid leukemia.
Da Qing Ye is used with other Chinese herbs
- It with Shui Niu Jiao (Cornu Bubali), Xuan Shen (Radix Scrophulariae), and Zhi Zi (Fructus Gardeniae) can treat high fever, unconsciousness, macules caused by seasonal febrile diseases.
- It with Ge Gen (Kudzu Root) and Lian Qiao (Fructus Forsythiae) can alleviate fever, headache, thirst, sore throat in the early stage of warm diseases or wind-heat syndrome.
- It with Sheng Di Huang (Radix Rehmanniae), Da Huang (Radix et Rhizoma Rhei), and Sheng Ma (Rhizoma Cimicifugae) can sore throat, aphtha, and tongue sore caused by the exuberance of heart and stomach fire.
- It with Pu Gong Ying (Dandelion), Zi Hua Di Ding (Viola Yedoensis), and Chong Lou (Rhizoma Paridis) can eliminate skin redness and swelling, treat erysipelas.
- It with Ban Lan Gen (Radix Isatidis), Jin Qian Cao (Lysimachia), and Da Huang (Radix et Rhizoma Rhei) can treat male condyloma acuminatum.
- It with Ban Lan Gen (Radix Isatidis) and Bai Hua She She Cao (Hedyotis Diffusa) can treat abscesses of palm and plantar.
Side effects of Da Qing Ye
Da Qing Ye has been used clinically for many years, with almost no side effects.
A small number of people taking it may cause nausea, vomiting, diarrhea, or hematuria.
Taking it in large doses may cause dilatation and congestion of the liver sinuses, atrophy of liver cells, and swelling and deformation of liver cells.
Precautions of Da Qing Ye
- The dosage of Da Qing Ye should be controlled at 9-15g.
- When using fresh Da Qing Ye, the dosage should be controlled at 30-60g.
- It can be made into decoction or mashed for external use.
- People with deficiency-cold in spleen and stomach should not take it.
- Pregnant women should not take it.