When it comes to Chinese herb of Hai Tong Pi, Erythrina variegata bark is one of the most common species. However, currently across China a variety of plants’ barks share this same name. As a matter of fact, the mainstream varieties come from as many as four families. Thus, so far Chinese pharmacopoeia failed to set a standard for this herb. Given the fact that different species are mixed currently, identifying the authentic one and defining its medicinal uses are particularly important for all TCM practitioners.
What is Erythrina variegata bark?
Apparently Erythrina isn’t the equivalent of its Chinese counterpart medicinally, which mainly refers to the dry bark or root bark of Erythrina variegata (syn. E. indica Lam., E. variegata var. orientalis (L.) Merr.) and Erythrina arborescens Roxb., plants in the family legume. Others also include Kalopanax septemlobus (Thunb.) Koidz. or K. septemlobus var. margnificus (Zabel) Hand-Mazz. in the family Araliaceae, Gossampinus malabarica (DC) Merr. in the family bombacaceae, and Zanthoxylum ailanthoides Sieb. et Zucc. ot Z. molle Rehb. in the family rutaceae. And Erythrina variegata is also known as Indian Coral Tree, Sunshine Tree, and Tiger’s Claw. And medicinally it has a few different common names, including coral bean bark, Erythrina bark, cortex Erythrinae, bark of oriental variegated coralbean or Himalayan Coralbean, and so on. In China, it is mainly produced in Zhejiang, Fujian, Taiwan, Sichuan, Guizhou, Yunnan and other places. It is usually peeled during summer and autumn for better medicinal quality. And then dry in the sun, cut into shreds, and use raw.
Erythrina variegata is one of subtropical and tropical trees with red flowers. It can grow up to 20 meters. Barks are gray-brown and branches are from pale yellow to yellowish brown, and densely covered with gray tomentum and black cone-shaped spines, which will shed two or three years later. Leaves are alternate or clustered on the top of branches. Racemes are tomentose and about 15cm long; peduncle is 7 to 10cm in length; corollas is similar to dish, bright red, and with 5-6cm pedals. Pods look like string beads and slightly bent. Seeds are 1 to 8 pieces, spherical, and dark red in color. And it flowers in March.
Health benefits of Erythrina variegata bark
Main chemical constituents are alkaloids, including erysovine, stachydrine, erysotrine, erysodine, erythraline, erysopine, erysopitine, erysodienone, erysonine, hypophorine, hypaporine methyl ester, N, N-dimethyltryptophan methyl ester, erysotine, erythratidine, epierythratidine, and 11-hydroxy epierythratidine. And it also contains warangalone scandenone, 5, 7, 4′-trihy-droxy-6, 8-diprenyliso flavone, erycrisfagallin, erythrabyssin-Ⅱ, phaseollin, phaseollidine, isobavachin, eryvariestyrene, stigmasterol, β-sitosterol, campesterol, amino acid, and organic acids. And next let’s see what exactly it can do to our health.
Modern pharmacological actions of Erythrina bark
1. It has anti-inflammatory, analgesic, and sedative effects; 2. It can enhance myocardial contractility;
3. It has antihypertensive effect;
4. It has inhibitory effect on Staphylococcus aureus and different degrees of inhibition on Trichophyton violaceum and other skin fungus.
Proven cortex Erythrinae herbal remedies
According to the description in Chinese Materia Medica, this herb is bitter and acrid in flavor and neutral in properties. And it covers three meridians of liver, spleen and stomach. Vital functions are dispelling wind and eliminating dampness, dredging blocked channels, relaxing the muscles and tendons, and killing parasites to relieve itching. Essential Erythrina variegata uses and indications are pain in rheumatoid arthritis, limbs and joint spasm, traumatic injury, scabies and eczema. Recommended dosage is from 6 to 12 grams in decoction or infused in wine.
1. Hai Tong Pi Tang. This formula comes from Yi Zong Jin Jian (Golden Mirror of the Medical Tradition). It is mainly designed for injuries from falls, fractures, contusions and strains. Other prime herbal ingredients include Tie Xian Tou Gu Cao (Herb of Intricate Clematis), Ru Xiang (Frankincense), Mo Yao (Myrrh), Dang Gui (Dong Quai), and so on.
2. Hai Tong Pi San. This prescription is from Jiao Qi Zhi Fa Zong Yao (Essential for Treating Beriberi). It is basically formulated for wind-damp induced swollen, heavy legs and contracture and pain in all joints. Other primary herbs are Ling Yang Jiao (Antelope Horn), Yi Yi Ren (Coix Seed), Fang Feng (Ledebouriella Root), Qiang Huo (Notopterygium Root), and more.
3. Shen Xian Tui Feng Dan. Shen Xian Tui Feng Dan comes from Bai Yi Xuan Fang (Precisely-selected Prescriptions). It is exclusively made for leprosy. Other herbs are Zhi Mu (Anemarrhena Rhizome), Bei Mu (Fritillaria Bulb), Wu Mei (Mume Fruit) and Gou Ji (Chain Fern Rhizome).
4. Hai Tong Pi Jiu (wine). It is commonly used for rheumatism, limb Spasm, and waist and knee pain or numbness. Other major herbs are Coix Seed, Sheng Di Huang (Rehmannia), Niu Xi (Achyranthes Root), Wu Jia Pi (Acanthopanax Root Bark), and more.
Erythrina variegata side effects and contraindications
To date no known adverse reactions and drug interactions about Erythrina variegata bark were reported. And AHPA rated this herb as class 1, in which herbs can be eaten free of worry within pharmacological dosage. However, TCM thinks that it is inadvisable to be used on the particularly condition of blood deficiency.