Medicinal plants used by traditional healers in Kancheepuram District of Tamil Nadu, India

An ethnobotanical survey was undertaken to collect information from traditional healers on the use of medicinal plants in Kancheepuram district of Tamil Nadu during October 2003 to April 2004. The indigenous knowledge of local traditional healers and the native plants used for medicinal purposes were collected through questionnaire and personal interviews during field trips. The investigation revealed that, the traditional healers used 85 species of plants distributed in 76 genera belonging to 41 families to treat various diseases. The documented medicinal plants were mostly used to cure skin diseases, poison bites, stomachache and nervous disorders. In this study the most dominant family was Euphorbiaceae and leaves were most frequently used for the treatment of diseases. This study showed that many people in the studied parts of Kancheepuram district still continue to depend on medicinal plants at least for the treatment of primary healthcare. The traditional healers are dwindling in number and there is a grave danger of traditional knowledge disappearing soon since the younger generation is not interested to carry on this tradition.


Background
Plants have been used in traditional medicine for several thousand years [1]. The knowledge of medicinal plants has been accumulated in the course of many centuries based on different medicinal systems such as Ayurveda, Unani and Siddha. In India, it is reported that traditional healers use 2500 plant species and 100 species of plants serve as regular sources of medicine [2]. During the last few decades there has been an increasing interest in the study of medicinal plants and their traditional use in different parts of the world [3][4][5][6][7]. Documenting the indige-nous knowledge through ethnobotanical studies is important for the conservation and utilization of biological resources.
Today according to the World Health Organization (WHO), as many as 80% of the world's people depend on traditional medicine for their primary healthcare needs. There are considerable economic benefits in the development of indigenous medicines and in the use of medicinal plants for the treatment of various diseases [8]. Due to less communication means, poverty, ignorance and unavaila-bility of modern health facilities, most people especially rural people are still forced to practice traditional medicines for their common day ailments. Most of these people form the poorest link in the trade of medicinal plants [9]. A vast knowledge of how to use the plants against different illnesses may be expected to have accumulated in areas where the use of plants is still of great importance [10].
In the developed countries, 25 per cent of the medical drugs are based on plants and their derivatives [11]. A group of World Health Organization (WHO) experts, who met in Congo Brazzaville in 1976, sought to define traditional African medicine as 'the sum total of practices, measures, ingredients and procedures of all kinds whether material or not, which from time immemorial has enabled the African to guard against diseases, to alleviate his/ her suffering and to cure him/herself' [12]. Traditional medical knowledge of medicinal plants and their use by indigenous cultures are not only useful for conservation of cultural traditions and biodiversity but also for community healthcare and drug development in the present and future [2].
Ethnobotany is not new to India because of its rich ethnic diversity. Jain [13] printed out that there are over 400 different tribal and other ethnic groups in India. The tribals constitute about 7.5 percent of India's population. During the last few decades there has been an increasing interest in the study of medicinal plants and their traditional use in different parts of India and there are many reports on the use of plants in traditional healing by either tribal people or indigenous communities of India [14][15][16][17][18][19][20][21]. Apart from the tribal groups, many other forest dwellers and rural people also posses' unique knowledge about plants [13].
The objective of this study was to interact with local traditional healers and document their knowledge on medicinal plants, their usage and the types of diseases treated etc. Kancheepuram is one of the 30 districts in Tamil Nadu and the traditional healing systems are still popular here. The present-day traditional healers are very old. Due to lack of interest among the younger generation as well as their tendency to migrate to cities for lucrative jobs, wealth of knowledge in this the area is declining. So far no systematic ethnobotanical survey has been made in this area and this is the first report on the medicinal plants used by the local traditional healers. A perusal of the literature reveals that, some of the ethnomedicinal works has been done in the forests of nearest districts in Tamil Nadu in the last two decades [22][23][24][25]. During the course of exploration of ethnomedicinal plants of the district, the informations have been gathered from the healers of rural villages found near forest areas where the people depend mostly on forests for their need and have sound knowledge of herbal remedies.

Materials and methods
The study area and ethnobotanical survey Tamil Nadu is the 11 th largest state in India with a geographical area of 130058 km 2 and lies between 11° 00' to 12° 00' North latitudes and 77° 28' to 78° 50' East longitudes. The total forest cover Tamil Nadu is 21482 km 2 (16.52%). This includes 12,499 km 2 of dense forests (9.61%) and 8,963 km 2 of open forests (6.91%). Of the total forest area of Tamil Nadu, 3305 km 2 are under protected area (15%) which includes, 8 Wildlife sanctuaries, 12 Bird sanctuaries, 5 National parks, 3 Biosphere reserves and one Tiger reserve [26].
Kancheepuram district in north Tamil Nadu ( Fig. 1) is placed 19 th in the forest cover with a geographical area of 4474 Sq.kms and recorded forest in the district is 5.32% [26]. This district is situated on the northern East Coast of Tamil Nadu and is adjacent to Bay of Bengal and Chennai city and is bounded in the west by Vellore and Thiruvannamalai districts, in the north by Thiruvallur and Chennai districts, in the south by Villupuram district and in the east by Bay of Bengal [27]. Paddy is the major crop cultivated in this district followed by groundnuts, sugarcane, Location of the study area Figure 1 Location of the study area. cereals, millets and pulses. The river Palar is one of the most important rivers running through the district. There are only a few hills of considerable elevation in the district [27].

Local traditional healers
Local traditional healers having practical knowledge of plants in medicine were interviewed in 12 villages of the district during October 2003 -April 2004. During the course of the study, four field trips were carried out in the study area totaling 40 days. Methods of selecting informants depended upon the distribution of local people having folk knowledge. They were requested to collect specimens of the plants they knew or to show the plant species on site. These informants were traditional healers themselves or had tradition of healing in their families and had knowledge of the medicinal use of the plants. Fuel wood from the surroundings was the main energy source for cooking and eating. The wealth of medicinal plant knowledge among the people of this district is based on hundreds of years of beliefs and observations. This knowledge has been transmitted orally from generation to generation; however it seems that it is vanishing from the modern society since younger people are not interested to carry on this tradition.

Interview with traditional healers
Adopting the methods of Jain [28], ethnomedicinal data were collected through general conversations with the informants. The questionnaires were used to obtain information on medicinal plants with their local names, parts used, mode of preparation and administration. A total of 10 informants, comprising 8 males and 2 females were identified between the ages of 48 and 74. They were selected based on their knowledge of medicinal plants either for self-medication or for treating others. Informants were asked to come to field and show the plants with local name; the species mentioned by the informants were taxonomically identified.

Preservation of plant specimens
Standard method was followed with regard to collection of plant materials, drying, mounting, preparation and preservation of plant specimens [29]. Voucher specimens of medicinal plants in triplicates were collected, prepared and identified. Plants with their correct nomenclature were arranged alphabetically by family name, vernacular name and ethnomedicinal uses. The identification and nomenclature of the listed plants were based on The Flora of Presidency of Madras [30] and The Flora of Tamil Nadu Carnatic [31]. They were later verified at Botanical Survey of India, Southern Circle, Coimbatore, India. All the preserved specimens were deposited at the Herbarium of Entomology Research Institute, Loyola College, Chennai.

Results
The results of the survey are presented in Table 1 and the families of the plants are arranged in alphabetical order. The present investigation comprises 85 species of ethnomedicinal plants distributed in 76 genera belonging to 41 families. For each species botanical name, family, local name, parts used, methods of preparation, administration and ailments treated are provided. Traditional healers are using these plants to cure diseases related to skin problems, cold, fever, cough, headache, diarrhoea, fertility problems, toothache, stomach ache, wounds, diabetes, rheumatism, asthma, dysentery, small pox, bone fractures, earache, hair loss and poison (snake, scorpion and insect) bites ( Figure 4).

Discussion
Different parts of medicinal plants were used as medicine by the local traditional healers. Among the different plant parts, the leaves were most frequently used for the treatment of diseases followed by whole plant parts, fruit, stem, root, stem and root bark, seed, flower and latex. The methods of preparation ( Figure 3) fall into four categories, viz.: plant parts applied as a paste (38%), juice extracted from the fresh plant parts (24%), powder made from fresh or dried plant parts (20%), some fresh plant parts (6%), and decoction (12%). External applications (mostly for skin diseases, snake bites and wounds) and Leaf paste is applied topically at the bitten site of snake, beetle and scorpion. Powdered leaf is mixed with cow or goat's milk and taken orally to treat diabetes. Asystasia gangetica (L.) T.Anderson (T224) Valukkai keerai Leaf powder is mixed with coconut oil and applied topically to heal wounds (burns). Thottasurungi Pinch of leaf paste is applied topically to treat cuts and wounds.  The fruit and root are mixed with boiled raw rice, taken orally to prevent white discharge in women and to treat urinary troubles. internal consumption of the preparations were involved in the treatment of diseases.
It was observed that, most of the remedies consisted of single plant part and more than one method of preparation. However, many of the remedies consisted of different parts of the same plant species to treat single or more diseases. For example, Andrographis paniculata -leaf paste is used to treat poison bites and leaf powder is used to treat diabetes; Gymnema sylvestre -root powder is used to treat poison bites and leaf powder is used to treat diabetes; Ricinus communis -juice extracted from leaves is used to increase secretion of milk and oil obtained from seeds is used to treat stomach ache; Azadirachta indica -leaf paste is used to treat small pox, rheumatism and skin diseases and young twigs are used as tooth brush; Ficus benghalensis -stem latex is used to treat heel cracks and young twigs are used as tooth brush; Moringa oleifera -boiled leaves are used to reduce body heat, to treat indigestion and eye diseases and flowers are used to cool the eyes and increase sperm production; Zizyphus mauritiana -decoction of leaf is used to get relief from body pain and bark powder is used to treat wounds; Solanum torvum -juice extracted from the leaf is used to reduce body heat and unripe fruits are used to strengthen the body.
Moreover a single plant is used for more than one disease. , Solanum torvum (to reduce body heat and to strengthening the body), Solanum trilobatum (cough and itching) and vitex negundo (headache, fever, cold and cough) and these recipes are prepared using different ingredients of non-plant origin such as water, salt, honey, etc.
Common health problems in the sites of the study area were skin problems such as wounds, cuts, burns and skin diseases and the largest number of the remedies (wounds Figure 3 Method of preparation.

Method of preparation
Habit Figure 2 Habit.
-16 remedies and skin diseases -9 remedies) was used to treat these troubles. Several studies have enumerated the plants used for wound healing and skin diseases in various parts of the world [14,[32][33][34]. 24 remedies were used to alleviate problems of the respiratory system such as cold, cough and asthma. Most of the plants in Lamiaceae were used to treat cold, cough, fever, headache and asthma. Ghorbani [35] reported 16 plant species that were used for respiratory diseases in north Iran and safety and efficacy of the treatments for respiratory track infections were reviewed [36]. Common ailments such as headaches or coughs are considered to be diseases with natural causes and hence their symptoms are treated at the household level, without resource to magical practices [12]. In the present study eight remedies (Terminalia arjuna, Leucas aspera, Ocimum sanctum, Sida acuta, Citrus aurantifolia, Cardiospermum halicacabum, Lantana camara and Vitex negundo) were used to get relief from headache. Recently Ignacimuthu et al [37] reported that Ceropegia candela-brum, Pergularia daemia and Vitex negundo were used by tribals for the treatment of headache.
Traditional healers of Kancheepuram district used nine plant species to treat stomach problems (three plants to treat stomachache and six plants to cure digestive problems). In North-Western Patagonia the people of Curruhuinca community were affected with digestive problems and the highest fidelity level was found for species utilized for treating digestive ailments [38] and Ghorbani [35] [21]]. Andrographis paniculata, Catharanthus roseus and Gymnema sylvestre were used to treat diabetes by the local traditional healers. Chherti et al [15] reported that the tribal people of Sikkim and Darjeeling Himalayan region in India utilized 37 species of plants belonging to 28 different families as antidiabetic agents.

Conclusion
The survey indicated that, the study area has plenty of medicinal plants to treat a wide spectrum of human ailments. Earlier studies on traditional medicinal plants also revealed that the economically backward local and tribal people of Tamil Nadu prefer folk medicine due to low cost and sometimes it is a part of their social life and culture [40][41][42][43][44][45]. It is evident from the interviews conducted in different villages, knowledge of medicinal plants is limited to traditional healers, herbalists and elderly persons who are living in rural areas. This study also points out that certain species of medicinal plants are being exploited by the local residents who are unaware of the importance of medicinal plants in the ecosystem.
This study concluded that even though the accessibility of Western medicine for simple and complicated diseases is available, many people in the studied parts of Kancheepuram district is still continue to depend on medicinal plants, at least for the treatment of some simple diseases such as, cold, cough, fever, headache, poison bites, skin diseases and tooth infections. Well-knowledged healers have good interactions with patients and this would improve the quality of healthcare delivery. The presentday traditional healers are very old. Due to lack of interest among the younger generation as well as their tendency to migrate to cities for lucrative jobs, there is a possibility of losing this wealth of knowledge in the near future. It thus becomes necessary to acquire and preserve this traditional system of medicine by proper documentation and identification of specimens.