Ethnomedicinal Plants Used by Malayali and Narikuravar Communities in Erode District, Tamil Nadu, India

Background: Traditional medicine plays an important role in primary healthcare of people reside in forest areas. We have reported the ethnomedicinal plants used by two ethnic communities in Western Ghats region of Erode district, Tamil Nadu, India. Aim of study: The aim of this study is to gather ethnomedicinal information from local people and herbalists and calculate the documented information with statistical parameters. Materials and methods: Semi structured questionnaire was used during the interview with Malayali and Narikuravar communities to document traditional knowledge on plants. The knowledge on medicinal plants used by informants to treat different types of ailments was analysed using the use value (UV) and frequency of citation (FC). Results: A total number of 69 species of medicinal plants belonging to 33 families have been reported to treat various illnesses. Most of the plants reported in this study were used to treat diabetes, joint pain, snake bite, kidney problems, uterine disorders, sexual and fertility problems, cough, indigestion and cancer. Moringa oleifera was reported with highest UV of 5.08. Conclusion: The present study revealed that, documentation of this knowledge will offer recognition of folk medicinal practices and could offer possible avenues for pharmacological analysis for a range of ailments.


Introduction
Nature is a source of biologically active compounds and documentation on traditional medicinal plants is an important facet to reveal the past and present culture, the source of fundamental knowledge for pharmacology, sustainable use and conservation of biological resources [1]. The use of herbal remedies as an alternative to conventional medicine is becoming increasingly popular due to lesser side effects. Traditional knowledge of plants and their properties has always been transmitted from generation to generation [2]. Documentation of indigenous knowledge through field studies among tribal communities is an important factor for conservation and utilization of biological resources [3]. Many ethnic groups rely on plants collected from wild habitats for their food and primary healthcare. The plants are reported to have rich in active biomolecules, thus knowledge on plant diversity of an area and traditional uses of those plants by indigenous communities is of prime importance for development of drugs in treating a variety of ailments [4].
India is one of the twelve mega-biodiversity countries of the world having a tradition of plant-based knowledge distributed amongst a vast number of ethnic groups [5][6][7][8][9][10][11]. In Tamil Nadu, 36 types of tribal and local communities are resides in forests and nearby areas. There are a number of ethno botanical researches is underway in Tamil Nadu and few hill areas inhabited by indigenous communities are still not studied in ethno botanical point of view. One such forest area is forests in Erode district of Western Ghats in Tamil Nadu, India. Hence, the present study was carried out among the Malayali and Narikuravar communities and local knowledgeable persons in the Erode district to document ethno medicinal knowledge of plants used by them.

Methodology
Malayali and Narikuravar ethnic communities inhabit the surveyed villages. Most of the ethnic communities and local people in these hills are using herbal medicines with a number of plants for their primary healthcare needs. The major livelihood of these people are agriculture, cattle farming, collection of fuel-wood and forest resources viz., herbal medicines, honey, edible fruits and tubers from nearby forests. Traditional healers of these communities acquired plant based knowledge from their ancestors. Some local people are collecting plant parts from forest areas and sell them to traditional healers who are professionally practicing herbal medicine.
The population of Malayali tribals is rich when compared to Narikuravar in Erode district. The detailed facts about the Malayalis were discussed in our previous publications [12,13]. In contrast to other tribal communities, Narikuravars (or Kuruvikarar) doesn't have particular place for their shelter and permanent hamlets. Narikuravars basically hail from a traditional hunting culture and they hunt fox, tiny wild animals and birds for their survival (www.tribalbharath.org). They live in groups, speak unique language "Vaghridholi" and find their foods from selling beads and leather made craft items. They also speak Tamil. Most of the people believe that buying fox teeth from Narikuravar will bring prosperity. They make camp tents on roadsides and under the flyovers for stay and source of livelihood. Occasionally they made a temporary settlement for staying in particular region during festivel times to sell forest resources. This community has unique customs and practices like dress habits, food habits and way of life of Narikuravar community in Tamil Nadu are different from other communities.
In order to document the utilization of medicinal plants, a methodical survey was carried out during July 2015 to August 2016 in the study area (Figure 1). During the course of time, 24 informants were identified, of which two were professional traditional healers (herbalists). Twenty two informants were local persons who had much knowledge on medicinal plants and practicing herbal medicines for their neighbourhoods. Age of the interviewed people is ranging from 31 to 72. The documented medicinal plants were collected for identification and preparation of herbarium specimens. The plant materials were preserved using standard methodologies and identified using 'The Flora of Tamilnadu Carnatic' [14]. APG III [15] was followed for nomenclature of plants and families. The scientific names of plant species were confirmed with the standard taxonomy database 'Plant List' (http://www.theplantlist.org). The voucher specimens were deposited in herbarium of A.V.V.M. Sri Pushpam College, Poondi (SPCH), Thanjavur, India for future reference.
Data associated with collected ethnomedicinal plants were sorted in MS Excel 2010 and analysed for descriptive statistical patterns viz., use value (UV) and frequency of citation. The knowledge on medicinal plants used by informants of study area to treat different types of ailments were analysed using above statistical formulae.
Use value (UV) was calculated to evaluate the comparative significance of traditional use of specific plant species by local communities [16].

UV=∑U/n
Where, U is number of use reports cited by each informant for a given plant species and n is the total number of informants interviewed for a given plant. The UV is helpful in determining the plants with highest use in the treatment of an ailment. UVs are high when there are many use reports for a plant and low when there are few reports related to its use.
Frequency of Citation of a plant species used was done using following formula, Where, N i is the number of times particular plant species was mentioned and ∑N i is the total number of times that all species were mentioned.

Medicinal plant diversity and their uses
In the present study, 69 species of medicinal plants belonging to 33 families were reported with the help of informants (Table 1)   The informants in the study area were practicing 9 types of preparation to treat different ailments. Of which mostly used herbal preparation was paste (28%) followed by plant derived raw material, powder, decoction and juice (16% eah) and remaining methods like soup, crushing, oil and emulsion (with 8%) with a very few preparations (Figure 4). For some herbal medicines with bitter taste, sweet ingredients like sugar, honey, jaggery (palm sugar) or milk were added during the preparation of medicines to reduce bitterness. Various application methods were exercised by studied informants, in which oral application (73%) was most commonly used than other modes like topical (23%), chewing (3%) and used as tooth brush (1%) (Figure 5). Similarly Nadembega et al. [17], Kadir et al. [18], Mahmood et al. [19,20] and Sadeghi et al. [21] also revealed that, oral application was most frequently used administration to treat several illnesses.

Quantitative analysis of data
Moringa oleifera was reported by most of interviewed informants and gives highest UV of 5.08 due to its diverse utilization among the interviewees. Majority of local people were using this plant to treat a variety of diseases mainly male erectile disorder, female infertility problems and cancer. Our previous report from Malayali tribals in Palamalai region of Tamil Nadu [13] and few more studies conferred the more or less same results [22,23].
Use value of a plant was considered based on the plant availability and accessibility and informant's knowledge. While plants with high UV were most preferred species in study sites and plants with low UV should not be neglected as failing to mention them to future generations could increase the risk of gradual disappearance of the knowledge from a particular community [24]. The plants with low UV for the reported plants may be due to its scarce availability in studied sites [25]. The frequency of citation was used to determine local importance of each species of a study area. In the present study Moringa oleifera was recorded with highest FC which tends to show that it was locally important among all interviewed informants to treat variety of diseases like male erectile disorder, premature ejaculation, infertility problems and cancer.

Special medicines to treat specific diseases
Most of the plants reported in this study were used to treat    diabetes, joint pain, snake bite, kidney problems, uterine disorders, premature ejaculation, other sexual problems, cough, indigestion and cancer. When herbalists prepare herbal preparations to treat various ailments, they frequently add some other plant parts, several ingredients and additives. Several previous studies by Ayyanar and Ignacimuthu [9], Keter and Mutiso [26], Kumar and Bharati [10] and Shah et al. [11] also supported this view.
Mixtures of several plant parts used in traditional healthcare practices were believed to exhibit synergistic interaction [27]. Apart from reported ethnomedicinal plants, informants of present study prepared fifteen types of medicines with mixture of several plant parts by means of particular names to treat specific illnesses ( Table 2). Of which Aalippodi used frequently to treat various illnesses like behavioural syndromes associated with physiological disturbances and physical factors, diseases of musculo-skeletal system and connective tissues, disorder of eye and adnexa and diseases of male genital organs.

Conclusion
The present investigation is first report from the Western Ghats region in Erode district to quantify the medicinal plants used by tribal and local people.