Assessment of Indian medicinal plants for the treatment of asthma

The present study documented the traditional knowledge of medicinal plants which are used for the treatment of respiratory diseases asthma in India by various tribal communities. The present study is based on the literature survey from various sources and it provides a comprehensive knowledge about the use of plants and their parts for the treatment of asthma by various tribal communities in India. Ethno-medicinal uses of 95 plant species along with their botanical names, plant family, part used, mode of administration and distribution of the plants in India were documented. They belong to 85 genera from 56 plant families. The present study provides the insight about the utilization of these plants by various tribal communities throughout India for the treatment of asthma.


INTRODUCTION
Plants are very useful source of various bioactive compounds which have direct or indirect use in the treatment of various human ailments.From the time immemorial, human civilizations have been exploring and using various plants and plant products to cure the deadly diseases.Asthma is one of the deadly diseases from which millions of people die every year throughout the world.It claims a fair share of casualties in India too.Asthma is a disease which affects the airways that carry air to and from lungs.People who suffered from this chronic condition (long lasting or recurrent) are said to be asthmatic.The most common symptoms of asthma include wheezing, coughing, chest tightness and shortness of breath.World Health Organization (WHO, 2001) surveyed that about 80% of the World's population, especially in the tribal and rural areas dependent upon herbal traditional medicines for their healthcare needs.It is estimated that 300 million people suffered from asthma worldwide (WHO, 2004) and around 255,000 people died due to this in 2005.Out of which 80% of asthma deaths were reported from low and lower middle income countries (Braman, 2006).
The use of plants and their parts as an ethno-medicine for the treatment of various diseases is a common practice among the tribal communities around the world since time immemorial.In India Rig-Veda was believed to be the oldest repository of human traditional knowledge about medicinal usage of plants which was written during 4500 to 1600 BC.There were number of plants documented in the Ayurveda and Unani system of medicines for the treatment of asthma in India.Likewise, indigenous knowledge has evolved independently in the different parts of the world which was used by tribal communities for the treatment of various diseases  (Jain and Sharma, 2000).However, due to the changing perception of the user communities, commercialization and socio-economic transformation all around the world, there has been a general observation that the indigenous knowledge on sustainable uses of resources has been degraded severely (Gadgil et al., 1993), and needs to be documented before it is lost forever to posterity.The present study is an assessment of the ethnobotanical usage of various plants reported in the scientific publications (books, research papers, short notes) for the treatment of asthma diseases by various tribal communities in India.

Collection of data
The data were collected for the present investigation through literature survey on various books of medicinal plants and their uses and through valued research papers published on ethnobotanical uses of medicinal plants (Kumari et al., 2014;Anjaneyulu and Sudarsanam, 2013;Bisht et al., 2013;Shyma and Devi, 2012;Taur and Patil, 2011;Sharama et al., 2010;Panda, 2010;Jitu, 2011;Reddy, 2008;Rajkumar and Shivanna, 2010;Singh et al., 2012;Patil and Patil, 2005;Singh, 2008;Silja et al., 2008;Bapuji and Ratnam, 2009;Noumi, 2010;Sharma et al., 2010;Bussmann and Glenn, 2011;Benniamin, 2011;Shanavaskhan, 2012;Shanmugam et al., 2012).In this survey, number of medicinal plants were explored which are very much useful for the treatment of asthma.Plant names have been arranged alphabetically and for correct nomenclature, Bennet (1986) quideline has been followed.Screening of collected data was carried with reference to the book entitled 'Dictionary of Indian Folk Medicine and Ethnobotany' by Jain (1991).The data were compiled with reference to the plant part used for the treatment of asthma, its administration and distribution of these plants in various parts of India.

RESULTS AND DISCUSSION
During the present survey, a total number of 95 plant species were explored which have potent use in the treatment of asthma disease (Table 1).These 95 species belong to 85 genera and 56 families of plants.Out of the total species, 91 were angiosperms which included 82 dicots and 9 monocots, while two species each belongs to gymnosperms and ferns, respectively (Table 2).Among these Cassia and Ranunculus were dominant genera with three species each, while Euphorbia, Ferula, Ficus, Fritillaria, Jucticia and Spaindus were represented by two genera each and the rest genera only represented by single species.The gymnosperm was represented by Taxus baccata and Abies pindrow plant species, while Ferns was represented by Dicranopteris linearis and Adiantum aethiopicum.The most dominant family for the treatment of asthma disease was Fabaceae with 11 species followed by Asteraceae and Euphorbiaceae having five species each, respectively.
Statistically, among the different parts of plants used for the treatment of asthma, the leaves of 19 plant species were used, 18 plants were used as whole, the roots were used from 12 species, the seeds were used from 8species, the fruit was used from 7 species, the stem bark was used from 6 species, the flowers and leaves along with roots were used from 4 species each, the root bark from three species was used, the leaves and flowers, rhizome and stem were used from 2 species each and bulb, culm, dried corms, fronds and wood were used from 1 species each, respectively (Figure 1).Among all the plants, 21 were used in the form of decoction, 20 in the form of powder and 12 in the form of extract and juice, respectively.The parts of 8 plant species were administered in the form of infusion.The fruits of five plants were directly eaten during the asthma problem.Smoke of 3 plant species, dry ash of 2 plant species and tonic of 2 plant species were used by the tribal communities for the treatment of asthma.Other plant species were administered as antispasmodic, expectorant, extract in oil, flowers directly eaten in the form of oil, folk recipes, paste, pounded with water, sedative and spasmodic for asthma treatment (Figure 2).
The knowledge about the use of herbal medicines gradually perishes, although some of the traditional tribal communities and some human beings which believed in the usage of herbal medicines are still practicing the art of herbal healing effectively (Raju, 1995).This study documented the usage of plant species by various tribal communities in India for the treatment of asthma.The knowledge about the ethnobotanical uses of these plant species and their status of distribution in India would be helpful in exploring these plant resources on large scale.These  traditional plant resources are under great demand by the pharmaceutical industries, for which they extracted several bioactive compounds for the preparation of novel drugs.Likewise, this study would also be explored by the common people for the treatment of asthma in herbal way.So, it is concluded that being more dependent on allopathic medicines for the treatment of asthma in modern times, the use of plant resources in the form of ethno-medicines by human-beings would play a vital role in the treatment of asthma in India.

Figure 1 .
Figure 1.Pie 3-D chart representing the statistics of different part of medicinal plants used for the treatment of asthma.

Figure 2 .
Figure 2. Pie chart representing different form of medicinal plant species taken for the treatment of asthma.

Table 1 .
Indian medicinal plants for the treatment of asthma.
Clerodendrum indicum (L.) Ktze.Verbenaceae Root Powder of roots eaten orally twice a day Cultivated for ornamental purposes in Madras, Kumaon, and from Sikkim to Assam Curculigo orchioides Gaertn, Amaryllidaceae Rhizome Juice, 15 ml mixed with honey taken twice a day orally Sub-tropical Himalaya from Kumaon east wards and in the Western Ghats
Fabaceae Root Roots juice, 50 ml taken twice a day orally Outer Himalaya up-to 5,000 ft. and throughout India Dicranopteris linearis (Burm.)Gleicheniaceae Fronds Extract of fronds in small amount taken per day In Hills throughout India up-to 6,000 ft Dorema ammoniacum D. Don Apiaceae Gum resin (Latex) It is expectorant, and eaten twice day orally Native to Persia.Cultivated in India Emblica officinalis Gaertn.Euphorbiaceae Seeds Seeds are mixed with Clove (Syzygium aromaticum) in equal amounts and roasted in a pan.The mixture is then powdered and 5g of it is given to the patient Common in the mixed deciduous forests of India ascending up-to 4,500 ft on the hills.Often cultivated in Gardens Ephedra gerardiana Wall.

Table 2 .
Statistics of type of medicinal plants used for the treatment of asthma.