BAMBOO AS MEDICINE

by Subhuti Dharmananda, Ph.D., Director, Institute for Traditional Medicine, Portland, Oregon

Bamboo is best known for its hard stems (culms) that are used in place of wood for a variety of applications, including furniture, scaffolding, flutes, fence posts, flooring, and even bicycle frames. Bamboos also serve as decorative plants, the source of tender shoots used in Chinese cuisine, and a primary subject of many Chinese artworks. Early Chinese books were written on bamboo slats and bamboo has been used as a source of medicine since ancient times.

Bamboo, a type of grass, is the fastest growing plant in the world. Some varieties grow at a peak rate of 5 cm (2 inches) per hour; more typical rates are 10 cm per day. Thanks to the strong stems, bamboo can tower several meters; the tallest reaching about 20 meters (over 60 feet). According to recent estimates, there are 36 bamboo forests still present in China despite intensive harvesting for centuries; they cover 4-7 million hectares (11-19 million acres) making up 3-5% of China's forests. China has an estimated 300 species of bamboos in 39 genera. India is second to China in bamboo harvest; it has larger bamboo forests, making up nearly 13% of the country's forest area. The annual global bamboo harvest is 10 million tons, and growing.

The plant is known in China as zhu; the Chinese character (above), which has been simplified from the ancient version, essentially shows two stalks of the bamboo plant topped with leaves. The shaved young shoots, the resin (both fluid and dried), and the leaves are all of medicinal value, with slightly differing applications. In general, bamboo is considered cooling, calming, and phlegm resolving. Although many species of bamboo are used as a source of medicinal products, the main ones are Phyllostachys nigra, the black bamboo (above), which grows abundantly along the Yangzi River, and Bambusa breiflora, Bambusa tuldoides, and Bambusa texilis (shown below; it is a frequent source of the resinous product called tianzhuhuang). The leaves most frequently used in Chinese herbal medicine are collected from another plant, Lophatherum gracile, the grass bamboo, one of the smallest of the bamboo-like plants. The medicinal products are described in the table, next page (1, 2). The liquid resin, zhuli, is usually not available outside of China, so the dried sap (tianzhuhuang) or the shaved stem (zhuru) are used as substitutes.

Bamboo Commonly Used in Chinese Medicine

All the bamboo materials have a mild sweet taste and all parts but the leaves are used to resolve phlegm. While the phlegm disorder to be addressed may be related to lung heat causing coughing and sticky phlegm, bamboo is especially used for the disorder of hot phlegm that coats or obstructs the "orifices of the heart," affecting the brain functions. Thus, it is used for epilepsy, fainting and loss of consciousness in feverish diseases, and a variety of mental disorders that develop with aging. Lophatherum (bamboo leaf) and bamboo shavings are commonly used in cases of stomach heat, providing a cooling effect and helping counter the perverse flow of qi (upward flow instead of the normal downward flow).

Bambusa texilis (weaver's bamboo), a frequent source of tianzhuhuang

Lophatherum (grass bamboo), a usual source of "bamboo leaf" in China

Tabasheer is one of the main substances from bamboo used in Ayurvedic and Tibetan medicine; it is often called bamboo-manna or bamboo silica (because it is rich in silica). Its properties include: stimulant, astringent, febrifuge, tonic, antispasmodic, and aphrodisiac. A major source in India is Bambusa arundinacea, though other species of Bambusa are also used. An Ayurvedic remedy, Sitopaladi Churna, was used traditionally for tuberculosis and other wasting diseases and has been adopted as a popular remedy for common cold, sore throat, sinus congestion, and cough. It is a powder (= churna) made with tabasheer as the main ingredient, plus small amounts of long pepper, cardamom, and cinnamon in a base of sugar. In Tibet, formulas with tabasheer as the main ingredient are used for treating lung diseases.

ACTIVE CONSTITUENTS

A number of studies of bamboo have yielded information about the chemical constituents, but no systematic evaluation has been carried out, so it is difficult to determine which of the identified compounds might be among the primary active constituents. It has been noted that the bamboo plant has unusually high levels of acetylcholine (which acts as a neurotransmitter in animals and humans; its role in plants is as yet unknown), especially in some portions of the plant (e.g., upper part of the bamboo shoot). It is conceivable that compounds of similar chemical structure in bamboo may contribute to the effects of the herb and its extracts on brain function. The bamboo leaves, obtained from the common tall bamboos (species of Phyllostachys, rather than the small Lophatherum) have recently been utilized as a source of flavonoids (e.g., vitexin and orientin), used as antioxidants. The flavonoids may reduce inflammation, promote circulation, and inhibit allergy reactions. A juice made from the leaves has been made into a bamboo flavored beer.

Chemical structure of acetylcholine.

BAMBOO IN TRADITIONAL FORMULAS

The following four tables present examples of traditional formulas that have incorporated bamboo (3, 4). The formulas have been divided as follows:

1. Bamboo leaf formulas for febrile conditions. Generally, these formulas were designed to treat an acute feverish disease that did not resolve in a few days, and sometimes caused a drying of the fluids (particularly of the stomach) as well as affecting the other internal organs. Typical symptoms are fever, irritability, and insomnia. The formula Zhuye Shigao Tang (Bamboo Leaf and Gypsum Combination) has been adopted in modern treatment of some chronic ailments, including diabetes.
2. Bamboo shavings formulas for upflowing qi from the stomach. These are formulas that are used for stomach heat syndromes that produce incorrect flow of qi, commonly causing nausea and loss of appetite, as well as symptoms of hiccups or vomiting (for acute and chronic cases). The formulas Jupi Zhuru Tang (Aurantium and Bamboo Combination) and Wendan Tang (Bamboo and Hoelen Combination) are widely used for these symptoms; the latter formula also addresses irritability and insomnia.
3. Bamboo shavings and tabasheer formulas for phlegm mist affecting the brain. These formulas clear heat and resolve phlegm to treat a syndrome in which "phlegm mist obstructs the orifices of the heart" (tanmi xinqiao) or, in cases where there is significant heat present, phlegm fire disturbing the heart (tanhuo raoxin). Symptoms may include severe agitation and insomnia, or convulsions (epilepsy, spasms, etc.), mania (emotional outbursts, incoherent speech), and even coma. The tabasheer formulas typically include many animal and mineral agents to make a highly potent (and toxic) treatment that can be given in very small amounts for only a few days; these were designed for treatment of infants. Ditan Tang (Phlegm-Scouring Decoction) and Zhuru Wendan Tang (Bamboo and Ginseng Combination) are non-toxic formulations with bamboo shavings that are still used today in the treatment of epilepsy (or other convulsive disorders) and mental illnesses (including those of children); these formulas can be used for prolonged treatment, if necessary.
4. Bamboo shavings and bamboo sap formulas for cough with excess sputum. Although bamboo is used in formulas for lung heat, especially when there is excessive sputum (often quite sticky in nature), it is not a common ingredient, since other herbs have very similar applications, particularly fritillaria, with which it is often combined. Both formulas listed are still in common use, primarily through Japanese and Taiwanese interest in them.

1. Bamboo Leaf Formulas for Febrile Conditions

2. Bamboo Shavings Formulas for Upflowing Qi from the Stomach

3. Bamboo Shavings and Tabasheer Formulas for Phlegm Mist Affecting the Brain

4. Bamboo Shavings and Bamboo Sap Formulas for Cough with Excess Sputum

APPENDIX 1: Differentiating Bamboo Materials Used in Chinese Medicine

In her book Chinese Herbal Medicines: Comparisons and Characteristics (5), Yang Yifang presents tianzhuhuang (dried sap), zhuli (liquid sap), and zhuru (bamboo shavings) in one section, while placing bamboo leaves in a separate section (differentiating two types), as follows:

Tianzhuhuang, zhuli, and zhuru are sweet and cold, and have the functions of clearing heat and transforming phlegm. However, the three enter different meridians and their strengths are different also, so their clinical applications are different.

Tianzhuhuang enters the heart and liver meridians and it is effective for dislodging phlegm, clearing heat, cooling the heart, and controlling convulsions. It is often used in children when there is high fever, irritability, convulsions, and night crying caused by disturbance of the heart and liver by phlegm-heat. It can also be used to treat fever, shortness of breath, and cough and thick sputum in conditions of phlegm-heat in the lung. In clinical practice, it is used for convulsions in infectious diseases, and for pneumonia, acute bronchitis, and influenza.

Zhuli is the coldest of these three herbs. It enters the heart, lung, and stomach meridians. It has a lubricating nature and its function is characterized as strongly eliminating phlegm-heat, especially when phlegm blocks the meridians and collaterals; therefore, it is used to treat epilepsy, hemiplegia, facial paralysis, and numbness and tingling or cramp of the limbs. It is able to open the heart orifice too, and is used when phlegm-heat covers the heart. In this situation, patients lose consciousness, and have gurgling sounds in the throat, such as occurs with epilepsy, stroke, and heart attack. Zhuli is also often used for treating mental disorders when phlegm-heat covers or disturbs the mind, such as in schizophrenia.

Zhuru is slightly cold and enters the lung, stomach, and gallbladder meridians. Besides clearing heat and transforming phlegm, it is effective for dispersing constrained qi, eliminating irritability, and calming the mind. It is mainly used for treating restlessness, palpitations, restless sleep, depression, and difficulty concentrating, especially after febrile disease or in chronic disease. It is also effective for soothing the stomach qi, clearing stomach heat, and treating nausea and vomiting, for example in morning sickness of early pregnancy, heatstroke, migraine, and Meniere's disease.

Zhuye can be divided into two kinds: the bitter form and the bland form. The bitter form is called kuzhuye. It is pungent, sweet, slightly bitter, and cold, and enters the heart and lung meridians. Pungency may disperse heat; bitterness and cold may clear heat. Kuzhuye is very effective in reducing heat in the chest and eliminating irritability. It is often used to treat febrile diseases when there is heat in the heart, lung, or chest. The bland form is called danzhuye. It is less strong in clearing heat than the bitter form, but is good at promoting urination, thereby leaching out the heat from the heart and the small intestine. In clinical practice, it is used to treat urinary dysfunction which starts or worsens in stressful situations. It is also used to treat eczema due to damp heat.

Dr. Jiao Shude (6) also presents some differentiation of the bamboo materials. He indicates the great value of zhuli (liquid sap) in treating stroke, epilepsy (and other "fright-wind" disorders in children), and coma. He notes that because of its cold nature it is best to combine it with several drops of ginger juice. He points out that the addition of ginger juice to bamboo sap "increases its ability to move through the channels and network vessels, move through the limbs, and to expel phlegm from outside the membrane within the skin [pili mowai]. The added ginger juice also prevents the stomach from being damaged by too much cold." The membrane he refers to is considered to be the body structure that is below the skin and encasing the organs, along the lines of the pericardium as viewed in Chinese medicine.

He points out that tianzhuhuang is often used in formulas in place of zhuli because of its lack of availability in the West, and that tianzhuhuang and zhuli "both clear heat and phlegm from the heart, but the former tends to be drying, whereas the latter has a lubricating disinhibiting nature." One might, therefore, use tianzhuhuang along with a lubricating herb such as ophiopogon or fritillaria to avoid the drying effect. Tianzhuhuang, he indicates, "has a special ability to clear heat and phlegm from the heart channel, open the orifices, and arouse the spirit, sweep phlegm, and stabilize fright." Jiao compares bamboo leaves with bamboo shavings as follows: Danzhuye clears upper burner heat and vexation, cools the heart, and disinhibits water; zhuru clears center burner heat and vexation, harmonizes the stomach, and checks vomiting.

In describing zhuye (bamboo leaf), the editor of the book suggests that the leaf of the black bamboo and of the grass bamboo are often confused both in China and the West. He notes that: "The strength of the black bamboo leaf is in clearing heart heat and engendering liquid, especially for contraction of heat patterns; lophatherum is most often used to clear heat and disinhibit urine in the treatment of urinary obstruction or mouth sores; it conducts heart heat out through the urine."

APPENDIX 2: Bamboo Vinegar

When bamboo is heated at very high temperature in an airless vessel, it becomes charcoal, which is used like other charcoal products, as a fuel component, a deodorizer, or an absorbent. The vapor that comes off the heated bamboo can be condensed to produce a liquid known as bamboo vinegar. It gets this name from the high content of acetic acid (the main component of ordinary fermented vinegar), though this ingredient is accompanied by many other compounds, especially phenols, such as guaiacol and cresol. Bamboo vinegar has been produced in Japan (where it is called chikusaku-eki) for many years and is used medicinally to treat eczema, atopic dermatitis, and other skin diseases; it is most commonly applied by adding to bath water. Bamboo vinegar is recognized as an anti-inflammatory and anti-fungal. It has recently been popularized as a main ingredient (along with the mineral tourmaline) in "sap sheets" applied to the feet to "draw out toxins." Since it is produced along with charcoal, a concern was raised about carcinogenic compounds, but it was found to be safe in initial screening and laboratory tests designed to detect such problems (7).

REFERENCES

1. Hsu HY, et al., Oriental Materia Medica: A Concise Guide, 1986 Oriental Healing Arts Institute, Long Beach, CA.
2. State Administration of Traditional Chinese Medicine, Advanced Textbook on Traditional Chinese Medicine and Pharmacology, 1995-6 New World Press, Beijing.
3. Huang Bingshan and Wang Yuxia, Thousand Formulas and Thousand Herbs of Traditional Chinese Medicine, vol. 2, 1993 Heilongjiang Education Press, Harbin.
4. Bensky D and Barolet R, Chinese Herbal Medicine: Formulas and Strategies, 1990 rev. ed., Eastland Press, Seattle, WA.
5. Yang Yifang, Chinese Herbal Medicines Comparisons and Characteristics, 2002 Churchill Livingstone, London.
6. Mitchell C, et al. (translators), Ten Lectures on the Use of Medicinals from the Personal Experience of Jiao Shude, 2003 Paradigm Publications, Brookline, MA.
7. Yuki K, Shiho S, and Masaaki T, Evaluation of carcinogenic/co-carcinogenic activity of chikusaku-eki, a bamboo charcoal by-product used as a folk remedy, in BALB/c 3T3 cells, Biological and Pharmaceutical Bulletin 25(8): 1026-1029.

December 2004