Herbal Textual Research of Inulae Flos in Chinese Classic Prescription

Xiaodu QIN, Houkang CAO, Zhipeng HUANG

School of Pharmacy, Guilin Medical University, Guilin 541199, China

Abstract The herbal textual research of Inulae Flos was carried out from the aspects of name, origin, habit and distribution, nature and flavor, meridian, efficacy and indications by referring to ancient Chinese herbal books and different editions of Pharmacopoeia of People’s Republic of China. After textual research, Inulae Flos has been named as "Inulae Flos" since Shennong Bencaojing (Shennong’s Herbal Classic). Its original plant is Inula japonica Thunb. or I. britannica L., which is easy to multiply and widely distributed. Inulae Flos is used medically with clean and dry capitulum, and there is also honey-burning method. The description of Inulae Flos in Pharmacopoeia of People’s Republic of China, such as nature and flavor, meridian, efficacy and indications, is generally consistent with the records in traditional herbal books.

Key words Inulae Flos, Herbal textual research, Origin

1 Introduction

The medicinal material Inulae Flos included in the 2020 edition ofPharmacopoeiaofthePeople’sRepublicofChina(hereinafter referred to asChinesePharmacopoeia) is the dry capitulum ofInulajaponicaThunb. orI.britannicaL.[1]. Inulae Flos is an important component of the ancient classic prescription Xuanfudaizhe decoction, which was first recorded inShanghanLun(Treatise on Febrile Diseases) in the Eastern Han Dynasty, and was mainly used for the treatment of epigastric fullness and rigidity, inexhaustible ructation[2]. Modern studies have shown that the main chemical components in traditional Chinese medicine Inulae Flos mainly are steroids, terpenoids, phenols, volatile oils, polysaccharides, flavonoids and other compounds, and have antioxidant, anti-inflammatory, anti-tumor, antibacterial, neuroprotection and liver protection effects[3-4]. The researches on Inulae Flos focus on modern pharmacology, while there are few researches on the textual research such as ancient Chinese herbal books. Therefore, the textual research of Inulae Flos was carried out from the name, origin, habit and distribution, nature and flavor, meridian, efficacy and indications, so as to analyze the historical facts of traditional medical use of Inulae Flos and to provide a reference for inheriting and developing traditional theoretical research and clinical application of Inulae Flos in modern times.

2 Alias and annotation name

Xuanfuhua (Inulae Flos) was first recorded inShennongBencaojing(Shennong’s Herbal Classic) of the Eastern Han Dynasty, "Xuanfuhua is also named Jingfeicao or Shengshen"[5], and Chinese herbal books of later dynasties also used this name. Since there were interchangeable words of "Hua" in ancient times[6], there was also another way of writing Xuanfuhua, such asBencaojingJizhu(Variorum of Shennong’s Classic of Materia Medica)[7]in the Southern and Northern Dynasties andXinjiuBencao(Annotation of Materia Medica)[8]in the Tang Dynasty. In the second half of the 20thcentury, several Chinese traditional characters of "Fu" were simplified, leading to the confusion of "Fu" in modern words[9]. Therefore, it was written as a character "Fu" in 1963 edition[10]and 1977 edition[11]ofChinesePharmacopoeia, but was written as another character "Fu" in the later editions.BencaoHuiyan(Collected Works of Materia Medica) in the Ming Dynasty said: "Xuanfuhua are round and covered, hence the name".BencaoGangmu(Compendium of Materia Medica) in the Qing Dynasty recorded: "The flowers are flourishing, round and covered, so it is called Xuanfu, and all names are got because of the shape of flowers"[12]. Thus, it can be seen that the origin of the name of Xuanfuhua is consistent with the appearance characteristics of "involucre consisting of many bracts arranged in imbricate pattern"[1], so the character "Fu" used in the current pharmacopoeia is more accurately than that in 1963 edition and 1977 edition.

BencaojingJizhu[7]in the Southern and Northern Dynasties,XinjiuBencao[8]in the Tang Dynasty,KaibaoBencao(Kaibao Materia Medica)[13]andZhengleiBencao(Classified Materia Medica)[14]in the Northern Song Dynasty all recorded: "Xuanfuhua is also named Jinfeicao, Shengshen and Daishen". In addition,JiuhuangBencao(Herbal for Relief of Famines)[15]in the Ming Dynasty also recorded that farmers called it Jinqianhua.BencaoMengquan(Materia Medica Companion)[16]in the Ming Dynasty also recorded: "Xuanfuhua, people also call Jinqianhua". There were many aliases recorded inBencaoGangmuin the Qing Dynasty, "Xuanfuhua, aka Jinfeicao (Benjing), Jinqianhua (Gangmu), Didijin (Gangmu), Daogeng (Erya), Xiaju (Gangmu), Daishen (Bielu)"[12]. The origin of the aliases of Xuanfuhua was described in some ancient books. It was recorded inBencaoHuiyanof the Ming Dynasty that "Xuanfuhua has dark yellow flowers in June, which also looks like chrysanthemum, with similar fragrance, so it is called Xiaju"[17].BencaoSanjiaHezhu(Co-edited Annotations of Three Books of Shennong’s Herbal Classic) in the Qing Dynasty said: "The grass named Jinfeicao gets the essence of water and dew and the heat of lung (gold); it is also known as Daogeng, with yellow flowers and white villi, and steals the qi of Gengjin in hot summer"[18]. Therefore, the origin of these aliases is related to their appearance and shape, and phenological stage.

In particular, Jinfeicao was used as another name or common name for Xuanfuhua in ancient times, but it is another Chinese medicinal material different from Xuanfuhua inChinesePharmacopoeia(2020 edition), namely the dry aboveground part ofI.japonicaThunb. orI.linariifoliaTurcz.[19]. In ancient Chinese herbal books, Jinfeicao generally appeared as another name for Xuanfuhua, and the two were not distinguished. Moreover, only Xuanfuhua was recorded in the 1963 edition ofChinesePharmacopoeia, but Jinfeicao was not recorded[10]. However, various editions ofChinesePharmacopoeiahave collected Xuanfuhua and Jinfeicao separately since the 1977 edition[11]. In addition, Jinfeicao was written as Jinfeicao in the 1963, 1977 and 1985 editions ofChinesePharmacopoeia[20], and changed to Jinfeicao since 1990 edition[21](except for the name, the contents of origin, character, identification, processing, nature and flavor, efficacy and indications, usage and dosage,etc., are basically the same).

To sum up, there are alternative names for Xuanfuhua in ancient Chinese herbal books, such as Jinfeicao, Daogeng, Shengshen, Daishen, Jinqianhua, Didijin and Xiaju (Table 1). However,ChinesePharmacopoeiahas distinguished Xuanfuhua and Jinfeicao as two kinds of Chinese medicinal materials. Therefore, it is no longer appropriate to use Jinfeicao as another name of Xuanfuhua.

Table 1 Names of Xuanfuhua and origins in ancient Chinese herbal classics

3 Textual research on origin

The description of the plant Inulae Flos in theFloraofChinais that "Rhizome short, traverse or ascending obliquely, with many stout fibrous roots; stem solitary, sometimes 2-3-fascicled, erect"[35], which is in good agreement with the root and stem of Inulae Flos picture (Fig.1A-F). The earliest description of plant height of Inulae Flos can be found inBencaoTujing[24]of the Northern Song Dynasty: "Inulae Flos is about one or two chi long", and the same record can be found inBencaoHuiyan[17]of the Ming Dynasty andBencaoshuGouyuan[34]of the Qing Dynasty,etc.According to textual research, one chi in the Northern Song Dynasty is equivalent to about 31 cm today[36-37]. Therefore, the plant height of Inulae Flos recorded in herbal books should be 31-62 cm, while that recorded inFloraofChinais 30-70 cm[35], and the height ofI.britannicaL. is also about 50 cm[38], so the height of Inulae Flos recorded in ancient books is consistent with the height ofI.japonicaThunb. andI.britannicaL. described today. In conclusion, the root, stem and plant height characteristics of Inulae Flos recorded in ancient herbal books are consistent with the botanical characteristics ofI.japonicaThunb. andI.britannicaL.

BencaoTujingin the Northern Song Dynasty recorded: "Leaves look like willow"[24], and Fig.1A-E show that leaves oblong-lanceolate, slightly pointed at tip, gradually narrowed at base, sessile, midrib and lateral veins obvious, without obvious concave and convex at leaf margins, which are consistent with the botanical characteristics of Inulae Flos[6, 35].I.japonicaThunb. closely resemblesI.britannicaL., and some scholars believe that the former should be a variant or subspecies of the latter. The taxonomic characteristics of the two are mainly distinguished by the basal shape of leaves. Compared withI.japonicaThunb. with narrowed base of leaves, the leaf base ofI.britannicaL. is broad, heart-shaped, auriculate, semi-amplexicaul[6, 35]. According to this feature, Fig.1F inAnIllustratedBookonPlantsin the Qing Dynasty is consistent with the botanical characteristics ofI.britannicaL.

Note: A. Suizhou Inulae Flos in Bencao Tujing of the Northern Song Dynasty; B. Suizhou Inulae Flos in Zhenglei Bencao of the Northern Song Dynasty; C. Suizhou Inulae Flos in Daguan Bencao of the Northern Song Dynasty; D. Inulae Flos in Jiuhuang Bencao of the Ming Dynasty; E. Inulae Flos in Bencao Gangmu of the Qing Dynasty; F. Inulae Flos in An Illustrated Book on Plants of the Qing Dynasty.

XinxiuBencaoin the Tang Dynasty said: "Inulae Flos looks like chrysanthemum but is bigger"[8]. According to the textual research of chrysanthemum records in ancient China, Chinese chrysanthemum changed from wild to cultivated in the Song Dynasty, and the flower diameter of chrysanthemum gradually increased. The flower diameter of chrysanthemum in the Song Dynasty was mostly 2.3-3.5 cm[39], and it can be speculated that the flower diameter of chrysanthemums in the Tang Dynasty was within this range or smaller, while the capitulum diameter of Inulae Flos was 3-4 cm (I.japonicaThunb. closely resemblesI.britannicaL., but differs by leaf shape and trichoma)[35]. Therefore, the description of "resembling chrysanthemum but bigger" of the original plant of Chinese herb Inulae Flos conformed to the morphological characteristics ofI.japonicaThunb. andI.britannicaL. Moreover, it is recorded inBencaoTujingof the Northern Song Dynasty that "Flowers are blooming in June, resembling chrysanthemum, which are dark yellow and about the size of a small copper coin"[24]. Coins in the Song Dynasty are mainly copper coins with various types. Referring to the diameter of "Sizhu" money in the Southern Song Dynasty of about 2 cm[40-41], it also basically conforms to the flower diameter ofI.japonicaThunb. andI.britannicaL. In addition, the lingual and tubular flowers ofI.japonicaThunb. andI.britannicaL. are yellow, which is consistent with the records of herbal books. For example, it is recorded as "deep yellow" inBencaoTujing[24]of the Northern Song Dynasty, "deep yellow like chrysanthemum" inBencaoMengquan[16]of the Ming Dynasty, and "blooming yellow with white villi" inBencaoSanjiaHezhu[18]of the Qing Dynasty. Moreover, attached pictures in ancient Chinese herbal classics show that Inulae Flos is conspicuously capitate, which is consistent with the inflorescence characteristics ofI.japonicaThunb. andI.britannicaL.[35,38]. The blooming time of Inulae Flos was recorded in ancient Chinese herbal classics[18,34,42], which is basically consistent with the flowering period ofI.japonicaThunb. (June to October)[35]andI.britannicaL. (July to September)[38]. In addition,I.japonicaThunb. andI.britannicaL. have a layer of crown hairs, about 20 pieces, white and rough[6, 35], which is consistent with the records of "yellow flowers and white villi" inBencaoSanjiaHezhu[18]of the Qing Dynasty, and "fine hairs" inBencaoHaili[26]andBencaoCongxin[32]. Therefore, the flower color, flower diameter, inflorescence, blooming period and crown hair of Inulae Flos are consistent with the botanical characteristics ofI.japonicaThunb. andI.britannicaL.

To sum up, the shape description of Inulae Flos (root, stem, plant height, leaf and flower) recorded in the ancient Chinese herbal classics is consistent with the botanical characteristics ofI.japonicaThunb. andI.britannicaL.

4 Genuine transition and quality evaluation of past dynasties

As for the habitat of Inulae Flos,BencaojingJizhuin the Southern and Northern Dynasties said: "Inulae Flos lives in flat lakes and river valleys, and grows towards the wetland from the nearest path"[7];BencaoTujingin the Northern Song Dynasty recorded: "Inulae Flos lives in flat lakes and river valleys, and grows near the water"[24];BencaoMengquanin the Ming Dynasty recorded: "Inulae Flos is clustered in deep valleys"[16]. Similar to the habitat description of Inulae Flos in ancient Chinese herbal classics, it is recorded in theFloraofChinathat "Inulae Flos is grown on hillsides and roadsides, in wet grassland, near river bank and on field ridges"[35], which means that Inulae Flos prefers a cool and humid environment, with relaxed requirements on soil[43]. However, there was no description of the specific location of Inulae Flos in ancient Chinese herbal classics. By referring to the annotation of "Suizhou Inulae Flos" in Fig.1A-C, it can be seen that Inulae Flos was distributed in Suizhou in the Northern Song Dynasty, roughly equivalent to Suizhou and Zaoyang in Hubei Province today[44]. Inulae Flos is very common in the north, northeast, central and eastern provinces of China, and can also be seen in Sichuan, Guizhou, Fujian and Guangdong[35]. Moreover,I.britannicaL. is suitable for growing in most parts of northern China, with drought, humidity and cold tolerance, and can be propagated by self sowing[38].BencaoChongyuanJishuoin the Qing Dynasty recorded: "According to legend, Inulae Flos will grow when the dews on leaves drop to the ground, so it is flourishing"[42], indicating that it can easily multiply and survive, consistent with the wide distribution or strong adaptability ofI.japonicaThunb. andI.britannicaL. In conclusion, the habits of Inulae Flos recorded in the ancient herbal classics are consistent with those ofI.japonicaThunb. andI.britannicaL., with relatively wide distribution, but there is no record of genuine production areas and quality evaluation.

5 Harvesting and processing

As for the harvesting period and processing method of Inulae Flos,BencaoTujingin the Northern Song Dynasty said: "Flowers are harvested in July and August, and directly exposed to the sun for 20 d"[24];BencaoMengquanin the Ming Dynasty said: "Flowers are harvested in July and directly exposed to the sun for medicinal use"[16], that is, the harvesting period of Inulae Flos is from July to August, which conforms to the flowering period of its original plant; then, it is sun-dried, which is basically consistent with the description inChinesePharmacopoeia(2020 edition) that "flowers are harvested in summer and autumn during blooming period, and dried in the shade or in the sun after impurities are removed"[1]. In addition, the processing method of Inulae Flos was recorded inLeigongPaozhiLunin the Southern and Northern Dynasties that the flower disc was only retained from inflorescence, which was first purified and steamed, and then dried. The purpose of purification of Chinese medicinal materials is mainly to retain medicinal parts and to remove non-medicinal parts and impurities[45]. According to the processing item of historical editions ofChinesePharmacopoeia, the stalk, leaf and impurities should be removed to obtain pure Inulae Flos. Steaming is a traditional processing technology, which can facilitate drying and reduce prickling sensation caused by certain substances[46].BencaoHailiin the Qing Dynasty recorded: "There are fine hairs that would attack lung and make people cough, and they should be wrapped in silk and prepared into decoction"[26]. Therefore, it is speculated that the advantages of steaming Inulae Flos may not only be beneficial to the subsequent drying, but also alleviate the cough caused by "fine hairs (crown hairs)".

ZhengleiBencaoin the Northern Song Dynasty recorded: "The empirical prescription is used for the treatment of apoplexia and stagnant syndrome; Inulae Flos is washed, smashed, and refined to honeyed pills; the patients are taken 5-7 or 10 pills with tea soup when lying at night"[14], that is, Inulae Flos is processed into honeyed pills by honey-burning method, but the processing method has not been found in most other herbal classics. Since Inulae Flos was included inChinesePharmacopoeia(1963 edition), Inulae Flos was processed by honey stir-frying method in subsequent editions ofChinesePharmacopoeia[10]. Honey-burning method prepares Chinese medicinal materials by making use of nourishment, moisten dryness and detoxification properties of honey, which is helpful to play the role of moistening lung and relieving cough or correcting drug bias[47].DaguanBencao[48]in the Northern Song Dynasty recorded: "Inulae Flos is slightly poisonous, but can be used to remove phlegm-heat accumulated in chest and thick sputum". Therefore, the purpose of processing Inulae Flos by honey-burning method is probably to reduce the toxicity and to increase the effect of resolving phlegm and relieving cough.

To sum up, Inulae Flos is generally harvested at flowering period in ancient and modern times, and is mainly processed by sun-drying. Steaming and honey burning are rarely recorded in ancient times. Purifying and honey-burning methods are included in various editions ofChinesePharmacopoeia.

6 Nature and flavor and efficacy

The evolution of the nature and flavor of traditional Chinese medicine Inulae Flos can be roughly divided into three periods. The first period is the Eastern Han Dynasty;ShennongBencaojing[5]recorded: "The taste is salty and warm", and the record was relatively simple. The second period is from the Southern and Northern Dynasties to the Tang, Song, Yuan and Ming Dynasties; many herbal classics generally recorded: "The taste is salty, sweet, (slightly) warm, cold, with (without) mild toxicity"[7-8, 13-14, 16, 25], and the description of nature and flavor was more detailed. The third period is the Qing Dynasty; the records of "salty and (slightly) warm" was also used in herbal classics, but the flavor changed from "sweet" to "bitter and pungent"[26, 28, 31]. The evolution of the flavor of traditional Chinese medicine is mainly due to the continuous development of five flavors identification method, namely from the direct tasting period to the five elements imaging and five tastes period, and then to the period of analogizing Chinese medicines with natural phenomenon[49].ShennongBencaojingin the Eastern Han Dynasty was the product of flavor discrimination transited from sensory experience (oral taste) to rational recognition (taste is combined with the theories of yin, yang, five elements, internal organs and meridians,etc.)[50-51], and had been constantly developed by medical experts of later generations, while the supplementation of "salty flavor" to "salty and sweet flavor" of Inulae Flos might be derived from the development of the five flavors theory of traditional Chinese medicine during this period. With the improvement of analogizing Chinese medicines with natural phenomenon, identification of drug flavor by analogy with drug efficacy had become the mainstream[52], and the flavor of Inulae Flos changed from "salty and sweet" to "salty, bitter and pungent" in the Qing Dynasty. This great change was in line with the wide application of the theory of analogizing Chinese medicines with natural phenomenon in the Qing Dynasty, and the description of "Inulae Flos bitter, pungent, salty and slightly warm" was also used in the 2020 edition ofChinesePharmacopoeia[1].

Similarly, the Qing Dynasty was the transition period, and there was no record of Inulae Flos meridian tropism in herbal classics before the Qing Dynasty. This was mainly because the theory of medicinal herb’s meridian tropism was formally proposed by Zhang Yuansu in the Jin and Yuan Dynasties, then developed into a more systematic theory of meridian tropism by Wang Haogu in the Yuan Dynasty, and continuously supplemented and improved by medical scientists of later generations[53]. That is to say, the theory of meridian tropism matured late, and it was only in the Qing Dynasty that the records of Inulae Flos meridian tropism began to appear. As for Inulae Flos meridian tropism,BencaoHaili[26]in the Qing Dynasty said: "Inulae Flos enters the lung, liver and large intestine";BencaoBeiyao[31],BencaoCongxin[32]andBencaoQiuzhen[28]said: "Inulae Flos enters the lung and large intestine". Many herbal books such asBencaoHuiyan[17]in the Ming Dynasty,BencaoBeiyao[28]andBencaoQiuzhen[31]in the Qing Dynasty all indicated that Inulae Flos had the effect of regulating spleen and stomach. Based on this, and considering that the determination of meridian tropism is based on the theory of internal organs and meridians, as well as the specific diseases and syndromes treated[54], Inulae Flos should also be attributed to spleen and stomach meridian. Inulae Flos included in 2020 edition ofChinesePharmacopoeiais attributed to the lung, spleen, stomach and large intestine meridian[1], which can be regarded as a summary of the understanding and theoretical derivation of the meridian tropism of Inulae Flos in the Ming and Qing Dynasties.

The record of the toxicity of Inulae Flos in Chinese herbal classics of past dynasties was generally "mild toxicity or non-toxicity", andChinesePharmacopoeia(2020 edition) did not describe its toxicity.Invitrostudies found that the active components of two sesquiterpene lactones (1-O-Acetylbritannilatone and britannin) of traditional Chinese medicine Inulae Flos had no obvious or low cytotoxic effects on human cervical cancer cells, human melanoma cells, human endometrial cancer cells, human liver cancer cells and other tumors[55]. In addition, some studies evaluated the subchronic toxicity ofInulanervosaWall., and the results showed that there were no significant abnormalities in general condition, hematological indexes and organ pathological observation of rats after continuous feeding at a dose of 8 g/kg for 90 d[56]. Although these studies can not directly prove the toxicity of Inulae Flos, they can indirectly provide a reference for its non-toxicity or mild toxicity, and its toxicological evaluation needs to be further studied.

The record of Inulae Flos efficacy was gradually detailed in the ancient herbal classics.ShennongBencaojingin the Eastern Han Dynasty said: "Inulae Flos is mainly used for the treatment of stagnation of qi, subcostal fullness, palpitation, removing water, removing cold and heat between the five viscera (a collective term for the heart, liver, spleen, ung and kidney), and nourishing the middle and lower qi"[5], but did not specify the corresponding symptoms.MingyiBieluin the Southern and Northern Dynasties began to have more specific records about the diseases treated, and recorded: "Inulae Flos is mainly used for removing phlegm-heat accumulated in chest, thick sputum, water retention of bladder, rheumatic arthralgia, carrion between skin, epiphora and swelling eye socket, and is benefit for large intestine, blood circulation and color"[33]. Except forRihuaziBencaothat newly added the content of "improving eyesight and curing head wind"[23], the records from the Southern and Northern Dynasties to the Tang and Song Dynasties basically followed the description of the ancient herbal books directly, without adding or supplementing the content[7-8, 13].TangyeBencaoin the Yuan Dynasty added: "After sweating and vomiting, the patients with epigastric fullness and ructation should be treated with Inulae Flos"[25], which quoted the description of the classic prescription Xuanfudaizhe decoction inTreatiseonFebrileDiseaseswritten by Zhang Zhongjing in the Eastern Han Dynasty. The records in the Ming and Qing Dynasties not only contained detailed indications of the symptoms, but also perfected the treatment mechanisms or taboos.BencaoGangmuin the Qing Dynasty is a collection of many classical books with detailed records, and recorded that "Inulae Flos is mainly used for treating stagnation of qi, subcostal fullness, palpitation, removing water, removing cold and heat between the five viscera, and nourishing the middle and lower qi; removing phlegm-heat accumulated in chest, thick sputum, water retention of bladder, rheumatic arthralgia, carrion between skin, epiphora and swelling eye socket, benefiting large intestine, blood circulation and color; treating edema, removing large abdomen, promoting appetite, stop vomiting…curing ructation"[12].

The herbal books of the Ming and Qing Dynasties have a relatively systematic theoretical exposition on the healing mechanism of Inulae Flos, such asBencaoHuiyan[17]in the Ming Dynasty. Ye Tianshi of the Qing Dynasty also elaborated the mechanism in detail[18], and it can be seen that there is a close internal relationship between the efficacy and flavor of Inulae Flos. The taboos of Inulae Flos were recorded inBencaoMengquan[16]of the Ming Dynasty andBencaoHailiof the Qing Dynasty[26], and it was clearly pointed out that Inulae Flos is not suitable for people with asthenic cold constitution.ChinesePharmacopoeia(2020 edition) is a collection of many classical books, which summarizes the efficacy and indications of Inulae Flos as "reducing qi, eliminating phlegm, removing water and stopping vomiting, treating cough with wind cold, phlegm accumulation, glomus and oppression in the chest and stomach duct, dyspnea and cough with excessive sputum, vomiting and ructation, and epigastric fullness and rigidity"[1].

7 Conclusions

In conclusion, there are many aliases of traditional Chinese medicine Inulae Flos, and there is confusion in the use of characters caused by the simplification of Chinese characters. Therefore, Xuanfuhua should be taken as the correct name, and it should be distinguished from Jinfeicao. The botanical characteristics ofI.japonicaThunb. andI.britannicaL. are consistent with the records of herbal books. Both of them are the original plants of traditional Chinese medicine Inulae Flos, which are easily multiplied and widely distributed. Inulae Flos is generally harvested at blooming stage, and purified dry capitulum is often used medically, or for honey burning. The nature, flavor, efficacy and indications of Inulae Flos described inChinesePharmacopoeiaare roughly consistent with the records of traditional herbal classics.