INTRODUCTION:

Plants have been great source of food and medicine for human beings since the birth of each and every civilization. Human have largely relied on medicinal plants to cure various ailments for several thousand years and this was common in all indigenous people throughout the world [1, 2]. Even today, 80% of the world’s population still depends on traditional medicine for their primary health care needs [3]. Medicinal plants used by indigenous people have been the source of modern drugs which has been obtained through experimentation [4]. India is amongst the most important medicinal collection centers of world. This could be asserted by the fact that India is considered as one among the 12 mega diversity countries of the world and home to 17000 flowering plants. Eastern Himalaya and Western Ghats are few amongst the hotspots of the world. Nearly, 2500 plant species of different formulations are in use as herbal drugs [5, 6]. It is estimated that over 6000 plants in India are in use in traditional, folk and herbal medicine which represents 75% of the needs of the third world countries [7].

The tribal and rural populations in Tamil Nadu are dependent of medicinal plants to meet their health care needs [8].

From the very earliest days of civilization, mankind has turned to plants for healing, a tradition that has survived the arrival of modern medicine and found new strength at the end of 20th century. Even today 80% of the world population relies on traditional plant medicine. According to Ayurvedic Materia Medica, there is no plant on earth which does not gave medicinal value. India is amongst the most important medicinal collection centers of world. Over 500 million people receive the benefits of traditional knowledge with nearly 460,000 practitioners of traditional system of medicine therefore it occupies the premier position in the use of herbal drugs utilizing nearly 2500 plant species of different formulations [6]. Over 7500 species of plants are estimated to be used by 4635 ethnic communities for human and veterinary health. The indigenous medicinal information of plants is helpful to ecologists, pharmacologists, taxonomists, watershed and wildlife managers in civilizing the prosperity of area, besides listing the traditional uses [2]. During the last century, various studies have been carried out to document the ethno-medicinal use of plant species growing in the region albeit. Most of these research efforts have been restricted towards chronicling of the medicinal plants used for treatment of human ailments [1, 3, 7].

Yelagiri is a hill station in Vellore district of Tamil Nadu, located between towns of Vaniyambadi and Jolarpettai, spread across the area of 29.2 km at an altitude 1048.5m above mean sea level. It is surrounded by orchards, rose gardens and green valleys. The maximum temperature during summer is 31⁰c and minimum temperature during winter is 11⁰c. The base of this hill is circular in shape and it has steep rock in its sides. It has evergreen trees in the north and north east slopes. On the top of the hill it has evergreen forest [9, 10, 11]. The present investigation gives an account of indigenous medicinal plants available in this hill area [6, 7, 8].

Table:- List of medicinal Plants found in Yelagiri Hills of Tamil Nadu :

S.No	Scientific name	Local name	Family	Parts used	Medicinal value
1.	Emblica officinalis	Nelli	euphorbiaceace	Fruit	Vitamin-C, Cough, Diabetes, cold,Laxative, hyperacidity
2	Withania somnifera	Amukkara	Solanaceae	Root/Leaves	Restorative tonic, stress, nerves Disorder, aphrodiasiac
3.	Phyllanthus amarus	Keela nelli	euphorbiaceae	Whole plant	Anemic, jaundice, Dropsy.
4.	Bacopa monnieri	Brahmi	Scrophulariaceae	Whole plant	Nervous,Memory enhancer,Mental disorder.
5	Tinospora cordifolia	Guluchi	-	stem	Gout, Pile, general debility, fever, Jaundice.
6	Gloriosa superba	Calihari	Lilaceace	Seed/tuber	Labour pain, Abortion, general Debility.
7	Solanum nigrum	Makoi	Solanaceae	Fruit/Whole plant	Dropsy, general debility, diuretic, Antidysentric.
8	Ranwolfia Serpentina	SarphaGandha	Apocynaceae	Root	Hypertension, insomnia.
9.	Asparagus Racemosus	Satavari	Lilaceae	Tuber	Enhance lactation, general Weakness, fatique, cough.
10	Casia augustifolia	Senna	Lilaceae	Seed	Rheumatism, general debility, Tonic, aphrodisiac.
11	Ocimum sanctum	Tulsi	Lamiaceae	Leaves/ Seed	Cough, Cold, bronchitis.
12	Mentha pipertia	Pippermint	Lamiaceae	Leaves, oil / Flower	Digestive, Pain killer.
13	Aloe vera	Gritkumari	Lilaceae	Leaves	Laxative, Wound, healing, Skin burns, ulcer.
14	Vinca rosea/ Catharanthus Roseus	Sada Bahar	apocyanaceae	Whole Plant	Leukemia, Hypotensive,antidote, antispasmodic.
15	Eclipta alba	Vringraj	Compositae	Whole plant/ Seed	Anti-inflammatory, Digestive, Hairtonic.
16	Plumbago zeylania	Swet chitrak	Plumbaginaceae	Root	Appetiser, Antibacterial, Anticancer.
17	Plumbago indica	Rakta Chitrak	Plumbaginaceae	Root	Indyspeipsia, inflammation Colic, Cough.
18	Terminalia chebula	Harida	Combretaceae	Seed	Trifala, wound, ulcer, leprosy, Inflammation, Cough.
19	Azadiratcha indica	Vembu	Maliaceae	Rhizome	Sedative, analgesic, epilepsy, Hypertensive.
20	Acorus Calamus	Bach	Araceae	Rhizome	Sedative, analgesic, epilepsy, Hypertensive.
21	Adhatoda vesica	Vasa	Acanthaceae	Whole plant	Antispasmodic, respiratory, Stimulant.
22	Mesua ferrea	Nageswar/ Champa	Guttiferae	Bark, Leaf, Flower	Asthma, Skin burning, Vomitting, Dysentry, Piles.
23	Centella asiatica	Mandukparni/Indianpennywort	Umdelliferae	Whole plant	Anti-inflammatory, jaundice, Diuretic, Diarrhoea.
24	Solanum Xanthocarpum	Kantakathri/ Akranti	Solanaceae	Whole plant, Fruit, Seed	treatment of toothache, chest pain due to cough, asthma and bronchitis
25	Lantana camara	Lantana/ Wild sage	Verbinaceae	Leaf	treat cuts, rheumatisms, ulcers, catarrhal infection, tetanus, rheumatism, malaria, cancer, chicken pox, asthma, ulcer, swelling, eczema, tumour, high blood pressure, bilious fever, ataxy of abdominal viscera, sores, measles, fevers, cold and high blood pressure
26	Cymbopogon citratus	Lemongrass / oil grass	Poaceae	leaf	treating cough, fevers, depression, nervous disorders, certain skin conditions, and acts as antifungal, antibacterial and antiseptic
27	Eucalyptus globulus	Eucalyptus tree	Myrtaceae	Leaf, oil	treating wounds, fungus, muscle pain, bruises, rheumatism
28	Artocarpus heterophyllus	jackfruit	Moraceae	Seeds, fruit, leaves	curing fever, boils and skin diseases, treating dysopia, opthalmities and pharyngitis
29	Mimosa pudica	Thottachinigi	Mimosoideae	Whole plant, Root	Nee burning, Eye disorder, Urinary inflammation, Kidney stone
30	Leucas aspera	Thumbai	Labiatae	Leaf, flower, Root	Vomitting, Dysentry, Skin disorder, Cold, Periods
31	Euphorbia hirta	Amman pachai	Euphorbiaceae	Whole plant, Milk	Pin worms, leprosy, nerves Disorder, pimbles, Breast feeding, Wound

MATERIALS AND METHODS:

Before starting the field work of medicinal uses of plants and the study area, general information about that area was collected from the local people. A preliminary survey was done along with a local person having knowledge of plants used traditionally as medicines. Surveys for ethnomedicinal exploration were undertaken during the December-April 2009 and August-November 2012 in the district yelagiri hills, particularly in the area of Nilavoor and Athanavur village. The local herbalists, old and experienced people were taken to the fields to identify the medicinal plants used in folklore. Each of the plant material was recorded in the field note book and photographs of plants were taken. To bring an element of accuracy, the information was cross checked with elderly people and local herbalists. The plant specimens collected from the area of survey were also authenticated from a registered institute and identified from the literature. Medicinal plant species of the area have been enumerated in table. List of traditionally used medicinal plants in yelagiri hills is given below as Table no. 1

RESULTS AND DISCUSSION:

The present investigation provides an ethno botanical data of the medicinal plants available in yelagiri hills. Some of the well-known medicinal plants like Ocimum sanctum, Leucas aspera have been utilized by the people of this locality to cure various ailments. But majority of the medicinal plants are least used as a curable source by the local practitioners and people. The thirty mentioned plant species belonged to fifteen families. Most of the plant species are wild and none of the medicinal plants are cultivated there. These plants have potential medicinal properties. The medicinal activities include anticancer, antidiabetic, antidote, antispasmodic, anti-ulcer, antibacterial, anthelminthic, antidysentric, anti-inflammatory, cure for various ailments like jaundice, epilepsy, piles, wound, skin burning, cough, asthma, bronchitis etc. Although there are plants belonging to different species, but the quantity of these plants except few are very low. Certain plants are gradually decreasing in numbers and seem to be in threatened condition in this area. There may be number of causes for the decline of medicinal plants, most notably due to the growth of herbicide Parthenium species. During the survey between 2009 and 2012, it was observed that this herbicide has occupied the places where herbs like ocimum sanctum and Leucas aspera survived. Other causes for the decline of medicinal plants are forest fire, excessive grazing of cattle. Lanta camara and Eucalyptus globus are few among medicinal plants which have dominated most of the hill area. These data are essential for conservation of medicinal plants in yelagiri hills as there has been no such study reported so far. The present study shows that the yelagiri hills have a great diversity of plants with potential medicinal values. Considering the growing threat of loss of medicinal plants, efforts need to be taken to conserve the threatened plants through conservation program and general awareness campaign among the public about protecting the medicinal flora from becoming endangered or extinct by means of forest fire and excessive grazing. Cultivation of some important medicinal plants needs to be considered as one of the methods of conservative program as the temperature of yelagiri hills are best suitable for this purpose. Checking the growth of herbicide is also necessary to protect medicinal plants.

ACKNOWLEDGEMENT:

We are thankful to the people of yelagiri hills who shared their knowledge regarding medicinal plants and their local uses. We are also thankful to Mr. M.P Afsar, my friend and colleague for helping us in this survey.

REFERENCES:

1. Sofowora, As., Medicinal plants and Traditional Medicinal in Africa. John Wiley and Sons, New York.1982.

2. Hills, A.F, Economic Botany: A Text Book of useful plants and plant products, 2^nd Edn., McGraw Hill Book Company, Inc., New York. 1989.

3. Dubey NK, Global promotion of herbal medicine: India opportunity, Curr Sci,. 86(1), 2004: 37-41.

4. Balick, J.M. and P.A. Cox,. Plants, People and Culture: the Science of Ethnobotany, Scientific American Library, New York. 1996.

5. Schippmann U, Leaman DJ, Cunningham AB. Impact of cultivation and gathering of medicinal plants on biodiversity: global trends and issues. In Biodiversity and the Ecosystem Approach in Agriculture, Forestary and Fisheries. Ninth Regular session of the commission on Genetic Resources for Food and Agriculture. FAO, Rome, Italy, 2002; 1-21.

6. Viswanathan MB, Ethnobotanicallly important plants, In: Tamil Nadu biodiversity strategy and action plant, wild plant biodiversity, by R Annamalai (Ed), Tamil Nadu Forest Department Chennai, 148; 2004, , 103-105.

7. Rajshekharan PE, Herbal medicine, In world of Science, Employement News,November (21-27), 2002; 3.

8. Ganesan S, “Traditional oral care medicinal plants survey of India”. Natural product radiance vol 7(2) ; 2008;166-172.

9. The Hindu, May 25,. “Miles to go for yelagiri hills as a tourist spot”. 2008.

10. Pullaiah, Rao Muralidhara T, Muralidhara Rao D, Sri Ramamurthy K,. “Flora of Eastern Ghats: Hill Ranges of South East India”. Daya books. ISBN 81-87498-49-8. 2002.Yelagiri Hill Development and Tourism Promotion Society, May 2008.

Received on 23.03.2013 Modified on 08.04.2013

Research J. Pharm. and Tech 6(6): June 2013; Page 652-654