Ethnobotany of the medicinal plants used by the ethnic communities of Kerman province, Southeast Iran

Abstract

Background

Traditional medicine is a major component in the primary healthcare system in the southeast of Iran, which has a rich floral diversity. However, there is no comprehensive report on the use of medicinal herbs in this specific region. This traditional usage of medicinal plants by local communities could serve as a source for pharmacological and phytochemical studies. The main objective of this study was to identify ethnopharmacological knowledge on medicinal plant species and their local healing applications by the folk communities of Kerman province in the southeast of Iran.

Methods

In this cross-sectional study, data were collected from 217 herbal healers using semi-structured questionnaires, open interviews, and field surveys. Factors including use reports (UR) for each species, frequency of citation (FC), and informant consensus factor (ICF) were used to analyze the data. Plant species were identified by botanists through standard taxonomic methods.

Results

A total of 402 medicinal plants were used in healing practices by the local communities of Kerman province. These species belong to 273 genera of 73 families, among which 367 species are dicotyledons, 27 are monocotyledons, 7 species are cryptogam, and one species is gymnosperm. An important implication from the current study is the identification of the traditional medicinal use of 292 plant species in this region for the first time. Asteraceae, Apiaceae, Lamiaceae, and Fabaceae were the dominant medicinally utilized plant families, respectively. Leaf, flower, fruit, and seed were the most common plant parts used. Generally, crude drugs were used in the form of decoction, followed by poultice and infusion forms. Moreover, oral route is considered as the most common administration route followed by topical route. Endocrine (diabetes), dermatological, gastrointestinal, and respiratory problems were ranked as the most frequent ailment categories for which medicinal plants in this region were applied, respectively. Our findings suggested dominant use of Asteraceae and Apiaceae plants for the treatment of gastrointestinal disorders, Lamiaceae plants for respiratory and gastrointestinal ailments, and Apocynaceae plants for dermatological problems.

Conclusion

Our findings suggested that Asteraceae and Apiaceae plants were used for the treatment of gastrointestinal disorders, Lamiaceae plants for respiratory and gastrointestinal ailments, and Apocynaceae and Euphorbiaceae plants for dermatological problems. Among the medicinal plants with high UR and new ethnobotanical uses, Rhazya stricta was used for wound healing, Calotropis procera, Clematis ispahanica and Euphorbia spp. for eczema, Cionura erecta for the treatment of cough, Launaea acanthodes for the treatment of gastrointestinal parasites, Berberis integrrima as an antidiabetic medicinal herb, Dracocephalum polychaetum and Rydingia persica for various types of chronic diseases, Citrus limon and Citrus aurantium for the treatment of ocular diseases and making the traditional kohl, Calendula officinalis for the treatment of pterygium and Prosopis farcta for preventing nasal bleeding. The identified medicinal plants can be further evaluated for their pharmacological activity and underlying mechanisms of action.

Introduction

According to the reports, medicinal use of plants dates back to at least 60,000 years. During this time, traditional systems of medicines have employed medicinal plants and their derivatives as valuable sources of new biologically active compounds and have been clinically practiced all over the world [1]. Until now, approximately 80% of the world’s population still use traditional herbal medicines [2]. In fact, herbal medicines can serve as complementary or alternative therapies for different types of diseases because of their low cost, availability, and generally fewer side effects [3]. Several FDA-approved drugs including artemisinin (from Artemisia annua), quinine (from Cinchona officinalis), vinblastine, vincristine, vinorelbine (from Vinca rosea), and etoposide (from Mayapple) primarily originate from traditional herbal medicines [4]. It has been estimated that nearly 400,000 flowering plant species exist on earth, among which only 6% have been evaluated for their biological properties, and still more than 90% remains unexplored [5]. Therefore, ethnobotanical study of medicinal plants provides valuable information for the synthesis of new drugs.

Around 8000 plant species have been listed in Iran, of which 2300 species have medicinal properties among which 75% (1728) are endemic species in Iran [6, 7].

Kerman province with 23 cities and 171,993 square kilometers area has covered about 11% of the land area of Iran [8], located in the southeast of this country, and bordered by 5 provinces of Yazd, South Khorasan, Hormozgan, Fars, and Sistan and Baluchestan. It has a unique biodiversity due to its diverse natural resources and climatic conditions including desert and semi-desert in the north, and dry, mountainous and Mediterranean in the south. Kerman province is a vast plain with the lowest altitude in Lut desert (300 m) and the highest altitude in the mountaintop of Hezar (4419 m) [8]. Based on the traditional pharmacopoeia and medicinal plant reports in some parts of this province, medicinal herbs mostly belong to the families of Labiatae, Rosaceae, Papilionacae, Compositae, and Umbelliferae, and the genera of Salvia, Nepeta, Artemisia, Astragalus, Ferula, Plantago, Ephedra, and Amygdalus [9, 10].

From the cultural point of view, Kerman province has around 89 tribal communities (including Baluch, Turkish, and Fars), most of them still being partially dependent on the medicinal plants. Therefore, this province is home to different cultures and beliefs resulting in rich traditional knowledge and traditional medicine practices. For example, the old city of Jiroft in the southeastern Kerman province dates to about 5000 years ago, which, according to the reports, is the beginning of human civilization [11]. In this respect, traditional medicine has played a key role in Iranian culture and civilization [12]. Therefore, this rich traditional knowledge is useful not only in the ancient medical systems but also in the present healthcare systems [10], especially for primary health care needs [13]. In fact, the dependence of the folk communities in Kerman on the medicinal herbs is not only due to the low availability to the health care system, but it is also rooted in the Iranian-rich culture of traditional medicine [14, 15]. For example, in the face of epidemiological diseases (e.g., cholera and colds), scientists of the Iranian traditional medicine (ITM) such as Avicenna, Rhazes, and Aghili Alavi Shirazi have suggested prescription of various herbal remedies. At present, the locals of Kerman, based on their ancient knowledge, utilize herbal medicines such as Thymus fedtschenkoi, Zataria multiflora, Dracocephalum polychaetum, and Glycyrrhiza glabra in the treatment of epidemics. Generally, Kerman province with a diverse climate and biodiversity is home to various cultures (from the prehistoric times to the present) and the center of agriculture in Iran [10, 16]. Accordingly, in some areas of this region, certain non-registered herbaceous species are used that can be obtained by the local people. There are many villages and nomadic districts that are largely dependent on the ethnomedicinal knowledge for primary health care, with many specific traditional herbal medicine practices in this region that have not been recorded anywhere else. Hence, the current study aimed to carefully investigate and record the ethnobotanical knowledge of the whole districts and cultures, particularly subcultures that had the maximum dependence on the traditional health care system of the Kerman province.

Materials and methods

Study area

The present study was carried out in Kerman province in the southeast of Iran with 23 cities and 3,164,716 inhabitants. Regarding population, the most populated city is Kerman with the following other cities as progressively less populated: Jiroft, Sirjan, Rafsanjan, Kahnuj, Rudbar, Anbarabad, Qale Ganj, Manojan, Faryab, Zarand, Bam, Fahraj, Narmashir, Rigan, ShahrBabak, Baft, Rabor, Orzueeyeh, Bardsir, Ravar, Anar, and Koohbanan. In the current study, in each city, skilled herbalists, nomadic districts, and key villages were selected for data sampling. Kerman province is located between the 55 min and 25° to 32° north latitude and 26 min and 53° to 29 min and 59° east of the Greenwich meridian, as the largest province in Iran with the total area of 183.285 km², and the elevation of 400 to 4501 m above the sea level. About 6.3 million hectares of deserts of Iran (equivalent to 20%) are located in Kerman province. The area of the forests of Kerman province is 1.3 million hectares and belongs to the two vegetation regions of Irano-Turanian and Khaleej-Omani.

Species of the Irano-Turanian forest of Kerman are comprised of Pistacia atlantica, Pistacia khinjuk, Juniperus excels, Prunus scoparia, Crataegus azarolus, Celtis australis in the mountainous area, and Haloxylon spp. and Calligonum spp. in the desert area. Also, the species of Khaleej-Omani include Calotropis procera, Tamarix spp., Prosopis spp., and Ziziphus spp. and the endemic rare species of Tecomella undulate with the local names Golpar and Anar sheytan (Fig. 1).

Fig. 1

Study area, Kerman province, southeast Iran

Plant identification

Based on the maps, access roads, natural features, vegetation, and subcultures in the study area, each city was classified into districts. Then, the number of the informants was determined. The plant specimens were collected during the field surveys from nomadic, rural, and urban areas of Kerman province from 2017 to 2019. The herbarium specimens were prepared following standard methods [17,18,19] and identified with the help of Herbarium of the University of Jiroft and Kerman Agricultural and Natural Resources Research and Education Center. Nomenclature was corrected using an online database (the international plant names index and the plant lists). The voucher herbarium specimens were deposited in the herbarium of the Department of Plant Biology, University of Jiroft, Jiroft, Iran. The voucher specimens were identified by one of the authors (H.B) and reaffirmed by taxonomic experts from the Department of Plant Biology at the herbarium of the University of Jiroft.

Ethnobotanical data collection

After classification of each city into districts, ethnobotanical surveys were carried out from October 2017 to the end of May 2019. The ethnobotanical data was collected using field surveys, open interviews, and semi-structured questionnaires. A total of 217 local informants (91 females and 126 males) aged between 30 and 79 years old were interviewed. Demographic properties including educational level, gender, age group, and occupation are recorded in Table 1. Also, geographical location and altitude (the lowest being 409 m in Manojan and the highest being 2800 m in Lalehzar) of each district are recorded in Table 2. Furthermore, information on local name, medicinal use, part(s) of the plant used, preparation, and administration methods is recorded (Table 3).

Table 1 Demographic profile of the local healers (n=217)

Table 2 Studied districts in the Kerman province with in-detail demographic characteristics of the local informants

Table 3 Medicinal plants used by ethnic communities in the Kerman province

Ailment categories

All recorded ailments and medicinal plant uses were categorized based on the International Classification of Primary Care (ICPC-2) (http://www.who.int/classifications/icd/adaptations/icpc2/en/).

Some modifications were made for diseases such as low back pain, which were not matched with the broad classification of diseases. Therefore, low back pain, infections, and some nontherapeutic applications (pickle, flavoring of food, appetizing, vegetable, thirst, pest control, food coloring, herbal adhesive, and washing powder) were placed in the General and Unspecified category.

According to the results, 16 disease categories were set, namely: (1) General and Unspecified; (2) Gastrointestinal; (3) Ophthalmological; (4) Ear, Nose and Throat; (5) Cardiovascular; (6) Hematological and immune mechanism; (7) Musculoskeletal; (8) Neurological; (9) Psychological; (10) Respiratory; (11) Dermatological; (12) Endocrine/ Metabolic and Nutritional; (13) Urological; (14) Pregnancy, Childbearing, Family Planning; (15) Female Genitals; and (16) Cancer.

Data analysis

Data was analyzed using descriptive and quantitative statistical methods. In this regard, the ethnomedicinal data was analyzed using frequency, citation, and use reports. Use report was recorded whenever an informant cited a plant species or part(s) used for a particular ailment. Use reports were also quantified to define the highly used plant species for a particular ailment. Additionally, ICF was employed to determine the homogeneity of the information as follows:

ICF = Nur − Nt / Nur − 1

Nur is the number of use citations for each ailment category and Nt is the number of plant species used for the same ailment category by all the healers [20]. ICF ranged between 0 and 1. ICF value is higher (near to 1) when a few plant species are cited by a higher proportion of healers, indicating homogeneity of information about the usage of specific plants. A low value (close to 0) demonstrates the healers’ disagreement about the usage of the plant for a particular ailment category [21].

In order to find out the importance of a specific plant species by informants, the index of relative frequency of citation (RFC) was calculated by dividing the frequency of citation (FC) by the total frequency of informants (RFC = FC/N). In this formula, FC is the number of informants who mentioned plant species as useful and N is the total frequency of informants in the survey [22].

Moreover, in order to determine cultural significance of each plant species, cultural importance index (CI) [22] was calculated as follows:

$$ \mathrm{CI}=\sum \limits_{u={u}_1}^{u_{\mathrm{nc}}}.\sum \limits_{i={i}_1}^{i_n}\ {\mathrm{UR}}_{\frac{ui}{N}} $$

Independent samples t-test was run to compare medicinal uses between men and women. One-way ANOVA and post hoc was used to compare medicinal uses among age groups, educational levels, and occupations.

Results and discussion

Botanical diversity

In this ethnobotanical survey which covered the whole Kerman province (23 cities and 3,164,716 population), a total of 217 local informant interviews revealed the application of 402 medicinal plants for the treatment of 95 diseases across 16 ICPC ailments categories. These results showed that herbal medicines are mainly used to treat ailments among the local communities and indicated the rich floral diversity of this region.

These species belong to 273 genera of 73 families where 367 species are Dicotyledons, 27 species Monocotyledons, 7 species Cryptogam, and one species Gymnosperm. An important implication of the current study is the identification of the traditional medicinal uses of 292 plant species in this region for the first time. Information about these recorded medicinal plants is summarized in Table 3 in terms of local names, voucher specimens, part(s) used, healing practices, drug preparation, ICPC classification, and use report (%).

Asteraceae, Apiaceae, and Lamiaceae with 43, 38, and 37 species were the dominant medicinally utilized plant families, respectively (Fig. 2). In the south of this province, Sadat-Hosseini et al. reported that Apiaceae, Asteraceae, and Lamiaceae are the dominant medicinal plant families [10]. Moreover, in several ethnobotanical studies in the neighboring provinces (in Sistan and Baluchesta [23], and in Isfahan [24]) and countries (like Turkey [25, 26], and Georgia [27]), similar results were reported on the dominance of two or three of these plant families. From the phytochemical point of view, the dominance of Apiaceae, Asteraceae, and Lamiaceae families might be due to phytochemical composition, which are clues to high content of essential oils and phenolic constituents responsible for antimicrobial and antioxidant properties [28, 29].

Fig. 2

Top dominants medicinally utilized plant families

Nepeta, Prunus, Ferula, Plantago, Ephedra, Euphorbia, Artemisia, Salvia, Artemisia, and Astragalus were the dominant medicinally used plant genera. Moreover, the findings of Saber et al. revealed that Salvia, Nepeta, Artemisia, Astragalus, Ferula, Plantago, Ephedra, Amygdalus, and Crataegus are the most frequently and popularly used medicinal plant genera in this district [8]. In general, the therapeutic significance of some plant families in a specific district may be related to the common distribution of their species [30].

There were some species like Tecomella undulata that were classified under vulnerable and endangered category of the IUCN list due to low reproduction and overexploitation [31, 32] while Pergularia tomentosa is a rare and endangered plant species which grows in the south of Kerman. Our previous research revealed that a low percentage of Kerman rangelands is vegetated with this plant and inhabitants uprooted it to meet their pharmacological needs [33].

The finding showed that the majority of the medicinal plant species (95%) belong to the wild habitat and the rest to cultivated areas. Other reports in this district [16, 27] confirm our results. In this case, informants of this region believed that wild plants are more medicinally effective than cultivated ones. Moreover, similar results were reported by Hu et al. in China [2].

With respect to healthcare policies, despite the relative adequate health services in this study area, local people and herbalists preferred herbal medicine due to the synthetic drugs side effects compared to herbal medicine. Furthermore, the general health policies that have been approved by the fifth development plan, as well as the national document on medicinal plants and traditional medicine, which emphasizes the organization and development of natural and traditional products, could play an important role in shaping people’s inclination towards traditional medicine [34]. Moreover, the medicinal plants’ availability, low cost, positive experiences, and reliable Iranian references like Avicenna could be the other reasons to form positive attitudes. Kerman province is a pivotal state in the ancient Iran (Persia) and it is estimated that the human civilization emerged from Jiroft in the south of this province [11]. Therefore, with a rich history, it has developed a sound traditional health care system.

Plant parts used

To prepare crude drugs (Fig. 3) from 15 plant parts, the most common plant parts used were leaf, flower, fruit, and seeds with 26.03, 15.36, 13.85, and 12.73 percentages, respectively. According to many reports, the leaf is the most common medicinal plant part used in the ethnopharmacological applications [35, 36]. Field discussion and other similar reports [30] indicated that availability, abundance, efficiency of use, and attention to the conservation points are the main reasons for the maximum usage of the leaves by local healers. In fact, local informants believed that different parts of the medicinal plants could have different therapeutic effects. In other words, plant organs have received varying degrees of attention based on traditional herbal medicine experiences of the ethnic communities. For instance, the root of Berberis integerrima is decocted and taken orally to treat diabetes while its leaf is used to treat hypertension. In addition, latex of Calotropis procera was used to cure eczema but its leaf is taken in the form of poultice to treat bruise and diabetes.

Fig. 3

Plant parts used in traditional herbal drug preparation and the number of use reports

Preparation and application modes

The medicinal herbs were prepared in 14 forms including decoction, poultice, infusion, aromatic water, powder, vegetable, maceration, syrup, mask, fume, brush, and shampoo by local communities. The most common form of the crude drug was decoction (52.99%), followed by poultice (18.32%) and infusion (7.56%) (Fig. 4). The local informants of Kerman province believed that by decocting the medicinal plants parts, their extract becomes more concentrated and obtains better taste and stronger efficacy. Based on various reports [9, 16, 37,38,39,40], decoction is the most common method to prepare herbal medicine.

Fig. 4

Crude drug type and the number use reports

The medicinal drugs administrated in six categories included oral, topical, dressing, eye drop, inhale, and bath. Analyzing the ethnobotanical data showed that the most common administration route was oral, followed by topical (Fig. 5). Other ethnobotanical studies in Iran and other countries revealed that ethnic communities mostly prefer these two methods of preparation [5, 10, 41]. But some plant species such as Lawsonia inermis, Juniperus excels, Rhazya stricta, and Pistacia atlantica are utilized in both topical and oral administration routes. For example, bath with the aqueous extract of Lawsonia inermis leaves is known as an effective method for the treatment of jaundice. The poultice of this plant is used to cure skin disorders like eczema and wound scar while its root is decocted and used orally as a diuretic and for the treatment of bronchitis.

Fig. 5

Mode of herbal drug administration and the number of use reports

Informant consensus factors (ICF)

The ICF values for different ailment categories treated by the local informants in this survey ranged from 0.25 to 0.92 (Table 4). Endocrine (diabetes), dermatology, gastrointestinal, and respiratory with 0.92, 0.91, 0.90, and 0.89 ICF, respectively, were ranked as the most popular ailment categories for medicinal plants in this region.

Table 4 Informant consensus agreement for ailment categories in the Kerman province

Diabetes disorder scored the highest ICF (0.92). This unexpected result is due to the high use report of few medicinal plants for treating diabetes mellitus such as Citrullus colocynthis, Berberis integerrima, and Tecomella undulata with 91, 61, and 41 use reports, respectively. In this case, C. colocynthis, a reputed medicinal plant in Kerman province, is well known due to its antidiabetic properties [42]. Moreover, in this case, the locals extremely used the root of Berberis integerrima and stem bark of T. undulata in treating diabetes mellitus. Field surveys and discussion with herbalists revealed that stress caused by poor economic conditions and job pressures can be one of the reasons for the high prevalence of diabetes in this region, but it needs more investigation.

Second ICF was found in dermatological ailment category with 1563 use reports. These findings are due to high use reports for plant species such as Calotropis procera, Pergularia tomentosa, Rhazya srticta, and Tecomella undulata in the treatment of eczema, wound healing, and other skin disorders. High ICF of dermatological disorders in this region might be due to high and long-term sunlight exposure, which caused skin disorders [10]. In addition, based on the field surveys, some environmental problems such as dust and wind associated with the particles of sands especially in the cities of Shahdad, Roodbar, Bam, Baravat, Qale Ganj, and Fahraj can be considered critical risk factors. Heidari et al. reported that the main reason for the skin diseases in the desert areas of the Kerman province like city of Bam is the dusty winds [43].

The third highest ICF (0.90) was found in gastrointestinal ailment category for 243 medicinal plant species. Species like Artemisa spp. Glycyrrhiza glabra and Nepeta cataria were typical medicinal herbs for gastrointestinal disorders. Such findings indicated the rich and high level of informant consensus on the variety of medicinal herbs used to treat gastrointestinal ailments, and confirmed the prevalence of gastrointestinal ailments among people who lived in a specific region [30]. Moreover, ITM (e.g., Canon) has attracted considerable attention for the treatment of gastrointestinal disorders [44, 45]. Several studies in Iran and other countries reported that the species Nepeta cataria [46, 47], Glycyrrhiza glabra [48, 49], and Artemisa spp. [50, 51] were traditionally used to treat gastrointestinal diseases.

The 4th disease category with ICF value of 0.89 was respiratory disorders. Zataria multiflora, Thymus fedtschenkoi, and Cionura erecta were major plant species for cough with 104, 102, and 87 use reports, respectively. The large number of use reports for respiratory disorder category might be attributed to undesirable working conditions of local populations, like agriculture and husbandry in the dry and dusty regions without quick access to the health care systems. In confirmation of the present findings, Khanjani et al. studied the relationship between air pollution and respiratory diseases in Kerman from 2006 to 2010 and reported that sandstorms and the dust content increase of the atmosphere exacerbate respiratory diseases in this region [52].

Use report

Medicinal plants of the families Lamiaceae (such as Nepeta cataria and Zataria multiflora), Asteraceae (like Artemisia persica and Launaea acanthodes), and Apiaceae (such as Bunium persicum) had the largest number of use report in this area. Bibak and Moghbeli, and Sadat-Hosseini et al. studied the medicinal plants of the Jiroft and Kanuj in the south of Kerman and, similar to the findings of the current study, confirmed the importance of traditional medication of these three families [10, 16]. In addition, plant species of the Apocynaceae family (like Cionura erecta, Rhazya stricta, and Calotropis procera) were ranked with a high use report. In this case, Cionura erecta is a well-known medicinal plant in the southern regions of Kerman for the treatment of sore throat and cough with no official records.

Cultural importance and relative frequency of citation index

The highest CI was found for Nepeta cataria, Zataria multiflora, Teucrium polium, Rydingia persica, and Thymus fedtschenkoi. The second highest CI was found for Dracocephalum polychaetum and Pistacia atlantica. These findings revealed that the first CI of the medicinal plants in Kerman province belonged to the Lamiaceae family. Additionally, Pistacia atlantica was ranked as an important medicinal plant with high CI index in this region. High CI values show that these medicinal plants are either highly utilized, or their uses are rising in traditional herbal medicine in a specific region [53].

However, for the RFC index, Lawsonia inermis, Artemisia persica, Zataria multiflora, and Nepeta cataria were classified as the first rank. In other words, the mentioned medicinal plants were referred by most of the informants. RFC value specifies the usefulness of medicinal plant species [5]. Table 5 shows the ranking based on each index (CI and RFC) for 20 dominant medicinal plant species with the highest CI and RFC indices.

Table 5 Comparison of dominant plants by using indices and species ranking based on each index (RFC and CI)

Based on the independent samples t-test, women had more knowledge about the medicinal plants (t = 1.87, p = 0.04). Based on the field surveys, women in Kerman province are the preparers of the plant species for the medicinal applications, and it can be concluded that women had more practical experience in traditional medicine in this region. The findings of Sadat-Hosseini et al. in the southern part of this region also confirmed our results [10].

The results of ANOVA showed that there were significant differences between the three age groups (F = 3.17, p = 0.02), and different levels of education (F = 2.56, p = 0.03). Also, based on Duncan’s test, the two older age groups (older than 45 years old) with low level of education had more traditional knowledge about the medicinal plants. Based on these results and other reports like that of Hu et al., despite the importance of the traditional medicine for the older inhabitants, the younger generation does not show interest, which means that the ethnobotanical knowledge does not further flourish [2].

Finally, based on the results of ANOVA and Duncan’s tests, occupation of the informants had a significant effect on their traditional medicinal knowledge (F = 4.19, p = 0.01), and genuine information belonged to the herbal healers, nomadic people, and villagers, respectively. Field surveys revealed that herbal healers, due to their job requirement, record and learn the relevant knowledge of the other ethnic groups like nomadic and villagers and usually have more comprehensive traditional knowledge.

Ethnopharmacological knowledge of tribes and different area

In the hot and dry regions of Kerman province like Kahnuj, Roodbar, Anbarabad, Qale Ganj, Manojan, Faryab, Bam, Fahraj, Narmashir, Rigan, and plain part of Jiroft, most inhabitants are from Baluch tribe and the natives of Jiroft and Kahnooj. Based on the results, medicinal plants such as Berberis integerrima, R. persica, Calotropis procera, and R. stricta are widely used to treat dermatological diseases. The rate of drug abuse in these regions is more than in mountainous areas because these cities are in the neighborhood of Afghanistan and the availability of drugs is thus higher. Hence, medicinal plants such as the plant from the genus Achillea (A. wilhelmsii, A. eriophora, A. santolinoides), Berberis integerrima, and R. persica are used individually or in combination by the locals for stopping drug abuse.

Tribal communities and folk people, who live in the mountainous areas such as Hezar, Sirch, and Jebal barez, mainly use the herbal medicine for the treatment of gastrointestinal disorders. Based on the field surveys and discussion with the herbal healers, the main food of the nomadic people is milk and its derivatives especially curd and buttermilk, and they do not have a diverse diet. There is a significant relationship between the consumption of low-diversity diets and the risk of non-communicable diseases [54, 55].

New traditional medicinal uses

According to the in-depth comparison of the current ethnobotanical findings with previous national reports, a large volume of unrecorded traditional medicine knowledge was gathered. A major implication of the current study is identification of traditional medicinal use of 292 plants in the Kerman province and 201 plants species in the Persian ethnobotany for the first time. This unrecorded knowledge is summarized based on the plant families as follows:

Amaranthaceae (Amaranthus retroflexus for the treatment of jaundice; Anabasis aphylla and Seidlitzia rosmarinus as traditional washing powders), Apiaceae (Eryngium billardieri and Eryngium bungei in pain relief, Prangos ferulacea as parasite repellents); Apocynaceae (Cionura erecta for sore throat and cough, Rhazya stricta for joint pains and body ache, Calotropis procera in the healing of skin disorders like eczema); Asteraceae (Launaea acanthodes as intestinal parasite repellents, Artemisia spp. for the treatment of gastric infection and stomachache, Calendula officinalis for the treatment of pterygium); Boraginaceae (Cordia myxa for common cold, sore throat and kidney stone); Ephedraceae (Ephedra distachya and Ephedra foliata for peptic ulcer and as materials in traditional tannery), Euphorbiaceae (Euphorbia serpens for eczema); Fabaceae (Astracantha lateritia for hair tonic and eczema, Prosopis cineraria for eczema and in traditional tannery, Prosopis farcta in preventing nose bleeding) Lamiaceae (Dracocephalum polychaetum as potent and multipurpose medicinal plant); Plantaginaceae (Plantago amplexicaulis, Plantago gentianoides and Plantago indica for constipation and jaundice); Polygonaceae (Pteropyrum aucheri in healing of infectious wounds); Ranunculaceae (Clematis ispahanica in healing of eczema and psoriasis); Rosaceae (Rosa moschata as nerve tonic, Prunus scoparia in cancer prevention); Rubiaceae (Plocama aucheri in reducing rheumatic pain and blood sugar); Rutaceae (Citrus limon and Citrus aurantium for the treatment of eye diseases and making the traditional kohl); Salvadoraceae (Salvadora oleoides as parasite repellent). Tamaricaceae (Tamarix aphylla and Tamarix kotschyi in healing of eczema and skin disease); Thymelaeaceae (Daphne oleoides in traditional dyeing); Violaceae (Viola odorata for chronic cough and as expectorant); and Zygophyllaceae (Zygophyllum eurypterum and Zygophyllum fabago as lactiferous and vermicide). These findings highlight the importance of the documentation of such valuable ethnobotanical information. Also, some of these medicinal plants can be targeted for pharmacological and bioactive studies with the aim of identifying phytochemical content and therapeutic applications.

Conclusion

Our extensive study in Kerman as the vastest province in Iran with 23 cities, 171,993 square kilometers area, and 89 tribal communities revealed rich traditional medicinal knowledge of its local populations. Traditionally, they used 402 medicinal plant species in 73 families to meet their pharmacological needs. Besides the common oral and topical utilization of the crude herbal drugs, dressing and bath with the medicinal plants are the exceptional mode of application in Kerman province. The highest ICF values belonged to diabetes, digestive, skin, and respiratory disorders, respectively.

Our findings suggested that Asteraceae and Apiaceae plants were dominantly used for the treatment of gastrointestinal disorders, Lamiaceae plants for respiratory and gastrointestinal ailments, and Apocynaceae plants for dermatological problems.

For several medicinal plants with high use reports such as Cionura erecta, Tecomella undulata, and Launaea acanthodes, scanty pharmacological and phytochemical data has been reported. On the other hand, the top list included Rhazya stricta: wound healing; Calotropis procera: eczema; Berberis integerrima: diabetes and addiction cessation; Dracocephalum polychaetum: stomachache, diarrhea, detoxification and strengthening body; Rydingia persica: leaving addiction; Launaea acanthodes: parasite repellent; Cionura erecta: expectorant; and Tecomella undulate: skin ailments, eczema, and diabetes. These results highlight the need for further bioactive and phytochemical studies on the mentioned medicinal plants. Finally, some frequently used medicinal plants like Cionura erecta, Dracocephalum polychaetum, and Tecomella undulate are endangered and restricted in small parts of their habitats. Therefore, urgent conservation measures are needed.