TURMERIC:
WHAT’S
IN AN HERB NAME?
HOW
TURMERIC (JIANGHUANG) AND CURCUMA (YUJIN) BECAME CONFUSED
BACKGROUND
The
naming of herbs that are botanically related or similarly used can sometimes
becomes confused. The source materials
that yield the pharmacy items can vary, and the applications of some herbs
overlap considerably and may be described differently by various authorities. That being, the ideal situation of having
one herb with one name and a clearly specified application is not always the
case. Turmeric is a good example of
this situation. Turmeric is one of
three herbs belonging to the plant genus Curcuma;
these herbs are not always clearly differentiated. This article traces the origins of the confusion in the English
language literature, and illustrates the complex nature of Chinese pharmacy
that all practitioners should be aware of in order to avoid problems in using
the available herbal materials. In
studying this subject, which requires detailed investigation of the herbal
materials, one will learn about how herbs are distinguished botanically,
chemically, pharmacologically, and clinically, as well as how they are depicted
in the traditional herbal literature.
The Oriental Healing Arts Institute (OHAI), founded by Dr. Hong-yen Hsu, was the originator of the common name terminology used by ITM since 1979 (see: On the common names for Chinese herbs). It was on the basis of the early work of OHAI that ITM has consistently used the common name turmeric to refer to jianghuang and the common name curcuma to refer to the Chinese herb yujin.
A few years ago, ITM received bottles of turmeric and curcuma extract for its granule pharmacy, and upon examining the contents I recognized that the material in the bottle labeled with the common name curcuma had the Chinese name jianghuang and contained the aromatic dark-yellow material that is well-known as turmeric. On the other hand, the bottle labeled with the common name turmeric had the Chinese name yujin, and contained another material, a lighter, less fragrant extract that had a color and fragrance consistent with pharmacy samples of yujin. While the term jianghuang undoubtedly applies to the substance in the first bottle, the common name curcuma didn’t seem correct; similarly, while the name yujin no doubt applied to the substance in the second bottle, the common name turmeric didn’t fit. It appeared that the common names of the herbs had been switched. Further investigation has revealed some difficulties in the description of source materials and reporting of therapeutic effects involving these two herbs and a third one that is related: zedoaria (ezhu).
Investigating the literature from OHAI, it appeared that a switching of the common names of turmeric and curcuma took place in the 1980’s, probably with the publication of the Oriental Materia Medica (12) in 1986. As a result of this switch, when ordering herbs by common name—from Brion Corporation, also founded by Dr. Hong-yen Hsu, and perhaps other organizations—one may obtain a different item than expected, and when reading materials from Oriental Healing Arts Institute published over a period of time, one may easily become confused about these materials.
CHANGING THE COMMON NAME
Turmeric, of course, is the name most people associate with the famous Indian spice that is a major constituent of curry powder, giving it the characteristic yellow color. In Webster’s Encyclopedic Dictionary this common material is what is represented by the primary definition of turmeric. However, reading down to the last definition in the dictionary, it turns out that the term “turmeric” may be used to refer to “any of various similar substances or plants.” Indeed, as one reads through some Chinese medical books, several species of Curcuma, the genus to which turmeric belongs, are referred to as types of turmeric. Here, we find the first aspect of naming confusion for these plants and the herbal materials derived from them.
The naming system adopted by
OHAI (around 1976) mainly relies on the use of genus names (Curcuma is the genus involved here), and
sometimes on other names, such as species names (e.g., zedoaria, from Curcuma zedoaria), or common names (e.g., ginger, another relative
of turmeric and curcuma in the same plant family but different genus). When there are several species of plants
belonging to the same genus and used in Chinese medical practice, the naming
system was set-up as follows: the botanical names are listed alphabetically by
species, and the first one is assigned the genus name as the common name; the
other ones are listed either by transliteration of the Chinese name, or by
species name or widely known common name.
In the case of the genus Curcuma, the three main sources in
alphabetical order are Curcuma aromatica,
Curcuma longa, and Curcuma zedoaria. The first was given the common name curcuma
(this is yujin), based on the genus;
the second was given its widely-used common name turmeric (this is jianghuang), and the third was assigned
its species name, zedoaria (this is ezhu). This assignment of species names is rare; in
this case it is appropriate because this herb is well known in India as
zedoary, which is how the plant got its species name.
Turmeric is so well-known in the world, from its use in making curry powder, Indonesian herb remedies, and as a source of dye, that it is only proper to assign this name to the herb that has this history. The Chinese name that goes with this herb is jianghuang, meaning ginger (jiang) that is yellow (huang). This name is certainly appropriate, as this is of the ginger family (Zingiberaceae), and it has a remarkable yellow color [note: such naming by color is not always so obviously connected to the herbal material that is actually used; the herb called huangjing, referring to Polygonatum sibericum, also has huang in the name, but the root material used for the herb is black].
Turmeric was probably originally imported to China from India. It did not appear in Chinese herbals until the Tang Dynasty, a time of great international trade. Turmeric is known to botanists either as Curcuma domestica or Curcuma longa: both names refer to the same plant. The term domestica is appropriate as this herb has been widely cultivated (i.e., domesticated) since ancient times. In China, this herb is usually traded in thick slices of bright orange-yellow color and characteristic fragrance.
On the other hand, there is
the herb known in China as yujin. The origin and meaning of the name is in
question, but yu refers to stagnancy
and constraint, while jin refers to
the metal element, and implies the lungs.
Thus, the early use of the herb involved treating stagnancy of the
lungs. The herb material lacks the
bright color of turmeric and it appears on the international market in the form
of very thin root slices. In China this
herb is differentiated into guangyujin (the
yujin used in Southern China, and
exported), which is from Curcuma
aromatica, and chuanyujin (the yujin used in Western China, not
exported as yujin), which is from
other species of Curcuma, including Curcuma longa, the source of
turmeric. This use of different species
within China is one reason why there is confusion about the source of the
material. In fact, other species have
also been recruited for use as yujin
(see Table 1). For southern China,
which has for years exported via Hong Kong to Taiwan and to the West, yujin is from Curcuma aromatica.
As part of the common name confusion, Curcuma aromatica is sometimes referred to in popular terminology as wild turmeric, even though it has been a cultivated herb for a long time. Further, the root slices are a relatively non-fragrant medicinal material, so that the term “aromatica” can only lend confusion. The top of the plant, especially the flower, is quite aromatic, accounting for the name.
In the Annual Reports of the National Research Institute of Chinese Medicine (11), there is an extensive report on Curcuma species used in Taiwan. In it, Curcuma longa, also listed as Curcuma domestica, is designated jianghuang, Curcuma aromatica is designated yujin, and Curcuma zedoaria is designated ezhu. These designations match those of the Illustrated Chinese Materia Medica (10), another Taiwanese publication. Two varieties of Curcuma aromatica are mentioned, one is called chuanyujin (i.e., Sichuan derived) and the other tuyujin (i.e., local) but the botanical sources are deemed the same. Another species of Curcuma is mentioned C. viridiflora, which is designated as erhuang (two yellow), and is considered a new medicinal species.
Turmeric (jianghuang) and curcuma (yujin) were labeled in accordance with this pattern in the early OHAI literature. For example, in the book Commonly Used Chinese Herb Formulas with Illustrations (1) there is one formula listed with turmeric and that is Chiang-huo and Turmeric Combination (Juanbi Tang). This formula is also mentioned in Chinese Herbal Medicine: Formulas and Strategies (2), calling for jianghuang as the ingredient, confirming the naming of jianghuang as turmeric.
In the OHAI Bulletin of 1983 (3), there is an article on herb processing that mentions these two herbs together, using the common names in proper order (i.e., consistent with the earlier publications). It is noted that “turmeric contains a much higher content of pigments than does curcuma,” which is certainly correct when the term turmeric refers to the common spice used in China as jianghuang. Further, it is mentioned that the essential oil turmerone exists only in turmeric (not in yujin), and this is responsible for the obvious fragrance of the herb. By contrast, yujin contains tolylmethylcarbinol, which is a cholegogue (causes the gall bladder to contract and spill bile into the intestines) that is present in only trace amounts in turmeric. Because of the action of this active constituent, yujin—but not turmeric—is mentioned in some Chinese texts as treating gallbladder congestion (which may further explain its actions of resolving phlegm accumulation and clearing heat, two results of proper gallbladder function).
Thus, these early OHAI publications apply the common names as one might well expect: turmeric for jianghuang and curcuma for yujin. In later books, however, the common names were reversed. Aside from Oriental Materia Medica in 1986, in which these are reversed, the formula Chiang-huo and Turmeric Combination became Chiang-huo and Curcuma Combination in the 1990 Commonly Used Chinese Herb Formulas Companion Guide (4), intended as an update on the former text, and in the 1992 Comprehensive Guide to Chinese Herbal Medicine (5). This explains why the bottles of single herbs obtained from Brion Corporation seemed to be reversed compared to my expectation.
CONFUSION OVER SOURCE MATERIALS
In the 1983 OHAI article on herb processing mentioned above, under turmeric and curcuma, the text also stated that: “Both herbs resemble each other in morphology and in herbal use, and since ancient times have been confused with each other and used interchangeably.” While the plant tops are no doubt similar (because the herbs come from the same genus of plants), the root materials, as described above, seem to offer little chance of mistaken identity (they differ in size, color, and fragrance). In fact, the confusion may lie in the simple fact that the herbs have been used interchangeably in some instances. Zedoaria has become enmeshed in this confusion of sources.
The source materials seem to have become confused, at least in the descriptive texts, because in different parts of China, different materials may be relied upon. In the Chinese-English Manual of Common-Used Herbs in Traditional Chinese Medicine (6), sources of the herbs are listed as follows:
Sources of ezhu:
Curcuma kwangsinensis
Curcuma aromatic
Curcuma zedoaria
Sources of yujin:
Curcuma aromatica
Curcuma
kwangsinensis
Under jianghuang, only Curcuma longa is mentioned.
In the Advanced Textbook of Traditional Chinese Medicine and Pharmacology (7), Thousand Formulas and Thousand Herbs of Traditional Chinese Medicine (8), and the 1988 Pharmacopoeia of the People’s Republic of China (9), the following are listed as source materials:
Sources of ezhu:
Curcuma aromatica
Curcuma kwangsiensis
Curcuma zedoaria
Sources of yujin:
Curcuma aromatica
Curcuma kwangsiensis
Curcuma longa
Curcuma
zedoaria
Jianghuang is not included in the Advanced Textbook..., but it is included in Thousand Formulas... and the Pharmacopoeia..., and its only source is Curcuma longa. So, it appears that the identity of turmeric is well-established, though this same source material appears as one entry under yujin. Interestingly, in the Pharmacopoeia..., under yujin, the common term is given as “turmeric root-tuber,” while under jianghuang, the common name given is “turmeric.” In Pharmacology and Applications of Chinese Materia Medica (13), under jianghuang it is mentioned that the plant source, Curcuma longa, is often used interchangeably with Curcuma aromatica.
These listings reflect the fact that yujin could be derived from Curcuma longa (as occurs in Sichuan Province), and that yujin and ezhu might come from the same plants. Despite all this, the raw materials (dried herb slices) obtained by ITM have not changed over the years, and each of the herbs appears entirely distinguishable. These herbs of the international market are pictured accurately (whole and sliced roots shown) in the Taiwanese book Illustrated Chinese Materia Medica.
Even though varying sources are reported in the Chinese Pharmacopoeia..., the description of the plant materials used in medicine is specified singularly, implying that a specific species is used as the reference:
Yujin: Root tubers are dug up in winter when the stems and leaves wither, removed from earthen matter and fibrous roots, steamed or boiled thoroughly, taken out and dried. Description: ovoid to long fusiform, some of them slightly compressed or curved, 2–6 cm long, 0.5–2 cm in diameter. Externally, greyish-yellow-brown to greyish-brown, longitudinally and disorderly wrinkled....Fractured surface horny, greyish yellow to greyish black, and exhibiting a pale-colored endodermis ring in the central part. Odor slight; taste bland.
Jianghuang: Collected in winter while the aerial part
withering, washed clean, boiled or steamed thoroughly, dried in the sun and
removed from fibrous roots.
Description: irregularly ovate, cylindrical or fusiform, frequently
curved, some Y-shaped branched, 2–5 cm long, 1–3 cm in diameter. Externally dark yellow, rough, with wrinkled
striations and distinct rings of leaf scars....Cut surface brownish yellow to
golden yellow, cuticle-like with waxy luster, endodermis ring distinct,
scattered with dotted vascular bundles.
Odor: characteristic fragrant; taste bitter and acrid.
Ezhu: Collected in winter while the leaves and stems withered, washed clear, steamed or boiled thoroughly and dried, then removed from the fibrous roots and foreign matter. Description: ovate, conical or long fusiform, 2–8 cm long, 1.5–4 cm in diameter. Externally, greyish-yellow to yellow-brown, annular nodes distinct, with round slightly sunken scars....Fractured surface yellowish-green to dark brown, waxy, endodermis ring yellowish-white....Odor: slightly fragrant; taste slightly bitter and pungent.
The color of the cut root and the odor and taste are evidently different from one herb to the next and correspond to samples obtained in U.S. markets and pictured in the Illustrated Chinese Materia Medica. Therefore, some of the source confusion seems to arise from simply providing comprehensive listings of both standard and substitute materials that have been used in China.
Species identification for the herb materials are presented in numerous illustrated Chinese materia medicas published in China. The following table presents a summary of information from these guides and the previously mentioned sources.
Table 1: The Main Curcuma Species Used as
Sources of Herbal Medicines in China.
|
Botanical
Name Commonly Mentioned |
Alternative
Botanical Names or Alternative Species |
Pinyin
Designations [Translations] |
Relation to
Herbal Materials |
|
Curcuma
aromatica |
=
Curcuma wenyujin |
yujin, wenyujin [gentle yujin], pian
jianghuang [slice turmeric], guangyujin
[Guangzhou yujin] |
Main
source of yujn; alternative source
of ezhu; rarely a source of jianghuang |
|
Curcuma
kwangsiensis |
none |
guangxi ezhu, maoezhu [fibrous ezhu],
guiezhu [cinnamon ezhu] |
Alternative
source for ezhu and sometimes for yujin; Guangxi Province is where it is
cultivated. |
|
Curcuma
longa |
=
Curcuma domestica |
jianghuang, chuan yujin [Sichuan yujin] |
Primary
source of jianghuang; source of yujin in Sichuan Province |
|
Curcuma
zedoaria |
other
sources, may be botanically indistinguishable: Curcuma aeruginosa, Curcuma phaeocaulis, Curcuma pallida |
ezhu, huopeng ezhu, peng ezhu [peng refers to luxuriant growth; huo means it is possible, but not
necessary] |
Main
source of ezhu, alternative source
of yujin |
DIFFERING PROPERTY DEFINITIONS
All three herbs, turmeric, curcuma, and zedoaria, are listed as blood-vitalizers in all modern texts. Still, the properties of these herbs, according to the Chinese materia medica books, are not all the same. As an example, yujin is cool, while ezhu and jianghuang are warm. The meridian attributes of ezhu and jianghuang are the spleen and liver, but for yujin they are the heart, liver, and gallbladder, or heart, liver, and lung (depending on source text; lung attribution is found in older works, gallbladder in newer works); some refer to it affecting the heart, liver, and stomach.
Turmeric is reported to be especially useful for treating pain syndrome (8), including pain in the chest and hypochondriac region, amenorrhea with abdominal pain, injury pain, and bi syndrome, especially in the shoulders. This last indication is the reason for its inclusion in Juanbi Tang, which is indicated for pain, especially in the neck, shoulder, and upper back.
By contrast, zedoaria is mainly used for abdominal pain. Like turmeric, it is to be used for abdominal pain with amenorrhea, and it is also used for distention and pain in the abdomen caused by food accumulation and stagnant qi. As a result of this latter indication, zedoaria is sometimes included in formulas to promote digestion and alleviate pain associated with digestive disorder. Still, in some books it is mentioned as treating pain due to injury, in common with turmeric.
Curcuma,
aside from vitalizing blood circulation, is used to regulate qi, cool the blood
and clear heat, and facilitate gallbladder function. Because of its ability to regulate qi—along with its cool energy
and its activating effect on the gallbladder—curcuma is sometimes used as a
substitute for bupleurum. Some doctors
suggest that bupleurum can have an action that is too harsh, while curcuma has
a similar but gentler action. Like
turmeric, it is used for pain in the chest, hypochondriac region, and abdomen,
and dysmenorrhea. Unlike turmeric, it
is not indicated for bi syndrome. Unlike both turmeric and zedoaria, it is
indicated for accumulation of turbidity that causes mental disorders, for
jaundice, and for spontaneous bleeding (due to blood heat).
The Pharmacopoeia... provides the following brief descriptions of actions and uses:
Yujin: To promote flow of qi, to eliminate blood stasis, to calm the nerves and ease the mind, and increase the flow of bile. Indications: amenorrhea, dysmenorrhea, distending or pricking pain in chest and abdomen; impairment of consciousness in febrile diseases; epilepsy; mania; jaundice with dark urine.
Jianghuang: To eliminate blood stasis, promote the flow
of qi, stimulate menstrual discharge, and relieve pain. Indications: pricking pain in the chest and
hypochondriac regions; amenorrhea; mass formation in the abdomen; rheumatic
pain of the shoulders and arms; traumatic swelling and pain.
Ezhu: To promote the flow of qi and eliminate blood stasis with powerful effect, and to relieve pain by removing the stagnation of undigested food. Indications: mass in abdomen; amenorrhea due to stagnation of undigested food; carcinoma of cervix at early stage.
In the Illustrated Chinese Materia Medica, it is further mentioned that yujin treats bleeding (“blood ejection, spontaneous external bleeding, blood in the urine, blood strangury vicarious menstruation”); that jianghuang treats kidney pain; and that zedoaria also dispels wind and clears heat (despite having a warm nature), and it alleviates menstrual blockage due to blood stasis and pain due to traumatic injury. Based on the listing of uses, it is clear that there is overlap in treating pain, but Chinese texts ascribe evidently different properties and uses to the three herbs. The variability of source materials that are reported, and the overlap of source materials, raises some questions about the importance of these differentiated applications in modern Chinese clinics.
USE OF THE HERBS IN TRADITIONAL FORMULAS
These three herbs are not frequently mentioned in
traditional formulas; curcuma (yujin)
and zedoaria (ezhu) have become more
widely used in modern prescriptions.
Zedoaria is often combined with sparganium (sanleng) in treating blood stasis, especially masses and
injuries. The following formulas
include the Curcuma species:
¨ Curcuma (yujin) is included in Guanxin Tang, a modern formula for treating coronary heart disease; Babao Ruisheng Dan, for treating cold in the spleen and stomach causing pain and food retention; Yujin San (translated as Curcuma Powder in Thousand Herbs and Thousand Formulas) for heat accumulation in the small intestine discharging to the bladder with blood in the urine; Angong Niuhuang Wan, for febrile disease causing mental disorientation; Biajin Wan, for epilepsy and other neurological symptoms due to phlegm accumulation; Yujin Yinzi, for febrile disease with clouding of the spirit.
¨ Zedoaria (ezhu) is included in the traditional formula Sanleng Heshang Tang, used for treating injuries, especially to the hypochondrium; Da Qiqi Tang, used for treating masses due to qi stagnancy and blood stasis, manifesting as soft and fixed abdominal masses; Neixiao Wan, a formula for qi stagnancy and food accumulation; Xiaoshi San, a formula for alleviating chronic food retention in children; Muxiang Binlang Wan, used for distention, fullness, and aching in the abdomen due to stagnation of qi and accumulation of dampness and heat; Sanleng Wan, for abdominal pain due to qi and blood stagnation in women; and in one of the versions of Wenjing Tang, used for lower abdominal coldness that causes lengthened menstrual cycle and menstrual blood clots with painful menstruation.
¨ Turmeric (jianghuang) is used in Zhixue Yuqi Zhi Fang, a formula used for regulating qi and blood circulation in cases of hypochondriac pain; Zhongman Fenxiao Wan, for fullness and pain in the abdomen due to stagnation of qi and accumulation of moisture; Juanbi Tang, a formula for pain (bi syndrome) in the shoulders, back, and neck; and Jianghuang San, a formula for pain in the heart.
The formula Jiuqi Niantong Wan includes both ezhu and yujin; it is used for treating stomach cold and abdominal pain, with qi stagnation and distention.
As can
be seen from the formula applications, in most cases the herbs are used in
accordance with their reported unique properties; hence, curcuma tends to be
used for heat syndromes, and especially those with neurological effects and/or
phlegm accumulation; zedoaria tends to be used for treating masses and food
accumulation; and turmeric tends to be used for pain syndromes. However, there are also peculiarities, such
as in the formula Babao Ruisheng Dan,
which would seem to call for zedoaria rather than curcuma as it treats a cold
stagnation of the spleen and stomach (the other herbs in the formula are
generally quite warming, so the use of zedoaria is not essential on account of
that). There is a report in Modern Study and Application of Materia
Medica (15) suggesting that Xiaoshi
San made with yujin in place of ezhu is useful for treating
gallstones.
PHARMACOLOGY
According to Pharmacology and Applications of Chinese Materia Medica and Chinese Herbal Medicine Materia Medica (14), in laboratory animal studies, turmeric has been shown to:
· reduce blood lipids
· improve blood circulation to the heart
· lower blood pressure
· reduce platelet aggregation and promote fibrinolysis
· increase bile formation and secretion
· reduce inflammation
· alleviate pain
· stimulate uterine contraction
In clinical trials, it was used to reduce blood lipids, treat angina pectoris, alleviate stomach ache, remove gallstones, treat jaundice, and relieve postpartum pain.
Zedoaria was reported to have the following actions in laboratory animal studies:
· antineoplastic effect
· prevention of leukopenia
· inhibit platelet aggregation
· stimulates the smooth muscle of the gastro-intestinal tract
In clinical trials, zedoaria was used to treat cervical cancer, where the essential oil of the herb is injected directly into the tumor (zedoaria is also used in decoctions for oral administration in the treatment of abdominal tumors). According to Modern Study and Application of Materia Medica, zedoaria has been used to treat coronary heart disease, liver cancer, anemia, and chronic pelvic inflammation. The use of zedoaria for cancer is elaborated in An Illustrated Guide to Antineoplastic Chinese Herbal Medicine (16); the herb is reportedly indicated for cancer not only of the cervix and liver, but also of the ovary, lung, and thyroid, for lymphosaracoma, and uterine fibroids. According to Anticancer Medicinal Plants (17), zedoaria not only inhibits cancer but also helps prevent leukopenia due to cancer therapies. Jia Kun (18) makes use of yujin as an important ingredient in his general anti-cancer pill called Pingxiao Dan, and also in several alternative decoction formulas for cancer, without specifying why this herb was selected, other than the fact that it disperses stagnation and activates the blood, which is also a property also of ezhu. He uses ezhu or jianghuang in some adjunctive formulas, but only rarely.
Pharmacology and clinical information about yujin used as a single herb is not commonly presented in the available texts. In Chinese Herbal Medicine Materia Medica, it was reported that curcuma could lower cholesterol in rabbits fed an atherosclerotic diet, and that it could alleviate the symptoms of viral hepatitis in humans. All three herbs appear to have potential value for preventing and treating cardiovascular diseases, as might be expected of blood-vitalizing agents. Both turmeric and zedoaria used in large doses would induce abortion in pregnant rats, confirming the traditional contra-indication of using strong blood-vitalizing preparations during pregnancy; traditional texts recommend that curcuma (yujin) be used cautiously during pregnancy.
CONCLUSION
Some confusion exists surrounding the sources, properties, uses, and common naming of three herbs of the same genus, jianghuang, yujin, and ezhu, but the problem is not so great in Southern China and outside of China where the market materials have remained consistent and the reported uses are also relatively consistent. Confusion of a similar nature may exist with a number of other Chinese herbs, making the study of Chinese herb resources more difficult, and demanding more knowledge of the peculiarities of local practices. It is possible that source materials vary in China because some doctors do not find it necessary to distinguish these herbs, dismissing the differentiated properties and uses. In fact, the use of substitute herbs in different parts of China is not uncommon and the herbs need not even come from the same genus, or even the same plant family to be used interchangeably.
The common name turmeric, if it is to be used at all, should always apply to jianghuang, which should be derived from Curcuma longa. According to the original naming system developed by OHAI, curcuma should be the common name for yujin and it should be derived from Curcuma aromatica, while zedoaria should be the common name for ezhu which is derived from either Curcuma zedoaria or Curcuma kwangsinensis. Using the pinyin will help avoid some confusion, but students and practitioners of Chinese herbal medicine should also recognize the somewhat fluid nature of herb selection for making prescriptions and the use of substitute materials in different regions of China.
REFERENCES
1. Hong-Yen Hsu and Chau-Shin Hsu, Commonly Used Chinese Herb Formulas with Illustrations, 1980 rev. ed., Oriental Healing Arts Institute, Long Beach, CA.
2. Bensky D and Barolet R, Chinese Herbal Medicine: Formulas and Strategies, 1990 rev. ed., Eastland Press, Seattle, WA.
3. Sheu AJ, Chen YP, and Hsu HY, A Study of Chinese Herbal Processing, Bulletin of the Oriental Healing Arts Institute of U.S. A. 1983; 8(5): 1–22.
4. Hong-Yen Hsu and Chau-Shin Hsu, Commonly Used Chinese Herb Formulas Companion Guide, 1997 rev. ed., Oriental Healing Arts Institute, Long Beach, CA.
5. Ze-lin Chen and Mei-fang Chen, A Comprehensive Guide to Chinese Herbal Medicine, 1992 Oriental Healing Arts Institute, Long Beach, CA.
6. Ou Ming, ed., Chinese-English Manual of Common-Used Herbs in Traditional Chinese Medicine, 1989 Joint Publishing Co., Hong Kong.
7. State Administration of Traditional Chinese Medicine, Advanced Textbook on Traditional Chinese Medicine and Pharmacology, (4 vol.) 1995–6 New World Press, Beijing.
8. Huang Bingshan and Wang Yuxia, Thousand Formulas and Thousand Herbs of Traditional Chinese Medicine, vol. 1, 1993 Heilongjiang Education Press, Harbin.
9. Pharmacopoeia Commission of PRC, Pharmacopoeia of the PRC, (English edition) 1988 People’s Medical Publishing House, Beijing.
10. Yen KY, The Illustrated Chinese Materia Medica, 1992 SMC Publishing, Taipei.
11. Lee TL, The pharmacognostical researches on the crude drugs of genus Curcuma in Taiwan, 1979 The Annual Reports of the National Research Institute of Chinese Medicine, pp. 95–117.
12. Hsu HY, et al., Oriental Materia Medica, 1986 Oriental Healing Arts Institute, Long Beach, CA.
13. Hson-Mou Chang and Paul Pui-Hay But (eds.), Pharmacology and Applications of Chinese Materia Medica, (2 vols.), 1986 World Scientific, Singapore.
14. Bensky D, and Gamble A, Chinese Herbal Medicine: Materia Medica, 1993 rev. ed., Eastland Press, Seattle, WA.
15. Dong Zhi Lin and Yu Shu Fang, Modern Study and Application of Materia Medica, 1990 China Ocean Press, Beijing.
16. Ou Ming, et al., An Illustrated Guide to Antineoplastic Chinese Herbal Medicine, 1990 The Commercial Press, Hong Kong.
17. Chang Minyi, Anticancer Medicinal Herbs, 1992 Hunan Science and Technology Publishing House, Changsha.
18. Jia Kun, Prevention and Treatment of Carcinoma in Traditional Chinese Medicine, 1985 The Commercial Press, Hong Kong.
March
1999
Figure 1: Curcuma aromatica, primary source of curcuma (yujin).
Figure 2: Curcuma kwangsiensis, alternative source for curcuma (yujin) and zedoaria (ezhu).
Figure 3: Curcuma longa, primary source of turmeric (jianghuang).
Figure 4: Curcuma zedoaria, primary source of zedoaria (ezhu).