Chapter 2 REVIEW OF LITERATURE

Transcription

1 Chapter 2 REVIEW OF LITERATURE 2.1 Ancient ethnomedicobotany: A global purview The plants have long been used as a source of medicine since ancient time to present day world over. The history of Materia Medica and plant taxonomy dates back to antiquity. It was essentially a folk taxonomy based on medicinal and economic plants, which herald modern phase of taxonomy. Prehistoric man has no less than a store house of knowledge about herbs and shrubs for curing their ailments besides knowing the economics of cultivated plants such as rice, wheat and wild vegetable plants. The primitive tribes in remote areas of world still have the tradition of preserving knowledge of the names and uses of plants through oral lore from one generation to another. Such classification systems developed by isolated communities through societal needs and without the influence of science are known to be folk taxonomy (Gurucharan, 1999). Throughout the ages, humans have relied on nature for their basic needs like foodstuffs, shelters, clothing, means of transportation, fertilizers, flavours and fragrances, and more importantly medicines. Plants have formed the basis of sophisticated traditional medicine systems that have been in existence since thousands of years (Berlin et al., 1966; Berlin, 1974; Fallarino, 1994, Newmaster et al., 2006, 2007). Like India, the Greeks were far ahead in the field of science and philosophy during ancient days. Theophrastus ( BC) the disciple of Plato and later Aristotle had accomplished 200 botanical works to his credit after inheriting the library and botanic garden from his teachers. He described about 500 species of plants, categorized into four major groups i.e. trees, shrubs, sub-shrubs and herbs. Several plant names used by him like Daucas, Crataegus and Narcisus are still in use today. The first records of Middle east human medicines, written on clay tablets in cuneiform, are from Mesopotamia and dates back to about 2600 BC; among the substances they used were oils of Cedrus sp. (cedar), Cupressus sempervirens (cypress), Glycyrhiza glabra (licorice), Camphora sp. (myrrh), and Papaver somniferum (poppy juice), all of which are still in use today for the treatment of ailments ranging from coughs and cold to parasitic infections and inflammation. Egyptian medicine dates back to about 2900 B. C. documented the use of 700 drugs, and includes formulas, such as gargles, snuffs, 9

2 poultices, infusions, pills and ointments, with beer, milk, wine and honey being commonly used as vehicles. The Chinese Materia Medica by Wu Shi Er Biing Fang of about 1100 BC includes 52 prescriptions which were followed by works such as Shennong Herbal Classic (100 BC) which mentioned 365 drugs (Porkert, 1974 and Fallarino, 1994). A very few of ancient taxonomists came to light in contemporary world through literature perusal who made remarkable contributions in Materia Medica and plant systematic. The work of Theophrastus De Cause Plantarum and the work of Parasar Vrikshayurveda were in quintessence world class Materia Medica text of ancient period who pioneered the ethnobotanical work to know the plants used in human welfare in systematic method. Uses of herbal drugs for treatment of various ailments in India dates back as early as 4500 BC with the oldest medical system in Indian subcontinent the Ayurveda which reported approximately 2000 medicinal plant species, followed by Siddha and Unani. Charaka and Shushruta (800 BC- 600 BC), Indian botanists during Vedic period were great healers who wrote the great volume like Charaka Samhita and Shushruta Samhita. Their herbal classic had quoted 341 and 395 species of medicinal plants and their indigenous uses respectively where Aconitum ferox, Acorus calamus, Aegle marmelos and Rauwolfia serpentina were prominently mentioned as potential crude drugs (Mukherjee, 1974; Prajapati et al., 2003). The fall of Greek empire saw the emergence of Roman Empire in Europe and Seucundus (23 A.D. to 79 A.D.) who served the Roman army was also a keen naturalist. He wrote Historia naturalis in 37 volumes and 9 volumes of which were dedicated to medicinal plants. Pedonius Dioscorides (100 A. D.) was a Greek physician who served Roman army and has made extensive tour in the forest and villages of Asia Minor to gain the first hand information about plants used in treating various ailments. He reported 600 medicinal plants in his outstanding work De Materia Medica with fine illustrations. The work was so popular that it ruled the medicinal plant systematic for nearly 15 centuries and no drug was considered genuine unless mentioned in the De Materia Medica. Tang herbal of Chinese (659 A. D.) contains 850 drugs was another source of folk medicine. Likewise, documentation of the system formed the basis for the primary text of Tibetan medicine, Gyu-zhi (four tantras) translated from Sanskrit during the eighth century A. D. (Fallarino, 1994 and Unschuld, 2003). Galen ( A.D.), who practiced and taught pharmacy and medicine in Rome published nearly 30 books to his credit and is well known for his prescriptions and formulas used in compounding 10

3 drugs, sometimes containing dozens of ingredients (galencilas). During the dark and middle Ages (5 th and 12 th centuries), the monasteries in England, Ireland, France and Germany preserved the remnants of the western knowledge, but it was the Arabs who were responsible for preservation of much of the Greco-Roman expertise. They were also responsible for expanding it to include the use of their own resources, together with Chinese and Indian herbs unknown to the Greco-Roman world. The Arabs were the first to establish privately owned drug stores in the eighth century, and the Persian pharmacist, physician, philosopher and poet Avicenna contributed much to the sciences of pharmacy and medicine through his remarkable pharmacobotanical works such as Canon Medicine, regarded as the final codification of all Greco-Roman medicine (Cragg & Newman, 2002) 2.2 Ethnobotanical study during last two centuries Modern ethnobiology begins in (Daniel, 1996). The first phase of ethnobiological research data of Europe and America on nutrition, medicines and industrial arts encountered among primitive tribes were presented by Ross (1861), Brown (1868), Palmer (1871), Rochebrune (1879), Powers (1875), Mathews (1886), Stearns (1889), Mooney (1891), Havard (1895), Coville (1895) and Mason (1899). Finally, it was William Hershberger (1896) who coined the term ethnobotany as use of plants by aborigines first initiated ethnobotanical work in global perspectives. Robbins et al., (1916) reported the ethnobotany of Tewa Indian in USA. Schultes (1962) advanced the same works in north and Latin America. Hora & Greenway (1940), MacMillan (1946), Willam (1949), Pursglove (1968), Shone & Drummond (1965), Blundel (1987), Shao et al. (1990) and Cunningham (1993) advanced the ethnobotanical work in tropical America, Asia and tropical East Africa. Lotschert and Beese (1983) reported tropical economic plants of Africa. Veerle and Patric (1996) reported 120 species of wild edible fruits as nutraceautical for tribals in Southern Equador. Zhao (2004) in his book Illustrated Chinese Materia Medica in Hong Kong reported 443 species of ethnomedicinal plants, 42 ethnomedicines of animal origin and 26 ethnomedicines of mineral origin which are widely used in modern Chinese and Indian Pharmacopeias. Out of the total 4,70,000 plants reported from the world, more than 50,000 are used for medicinal purposes (Govaerts, 2001; Schippmann et al., 2002). The nature and scope of ethnobotanical studies were mostly highlighted by Jones (1941,1962). Several workers have made significant contribution in 11

4 ethnobotanical and pharmaceutical drug development at global level where the work of Farnsworth and Bingel (1977), Cox (1994), Fabricant and Farnsworth (2001); Foster and Anderson (1978), Ford (1978) and Oslen (1998), Iqbal (1993) are notable. Out of 119 plant based drugs today, about 74% are from traditionally used as herbal cures (Holmes, 1884). At least 50 pharmaceutical drugs have been discovered from ethnobotanical leads (Bentley and Trimen, 1880). Holmes, between the years documented ethnobotanical plants of Singapore and South Asia. The science of ethnobotany has often been criticized for focusing on listing of plants and lacking of rigid methodology till late 80 s of the last century and it has been felt in recent years that such criticisms are not entirely baseless (Jain, 1995; Martin & Semple, 1994; Martin, 1995; Phillips, 1996; Phillips et al., 1994; Peters, 1996; Begossi, 1996). The quantitative methods to collect and analyze data using statistical tools have produced notable findings in ethnobiology research (Jain, 1995). To assess the ethnobotanical knowledge of individuals is the common application of quantitative methods in ethnobiology (Phillips and Gentry, 1993a, 1993b). Methodological contribution is an important area that has been perceived as essential in many branch of science and any researchers have shown concern with lack of methodlogical advances in contemporary ethnobiology (Guest, 2002). Ethnobiolo- gical research was basically descriptive prior to 1950s but by 1980s, researchers had rapidly incorporated a variety of quantitative methods of data collection and data analysis (Begossi et al., 2002). Quantitative methods in ethnobiology-ethnobotany, ethnoecology, ethnomedicines that shared ideas with other biological, social and linguistic sciences are proliferating at present (Phillips et al., 1994; Stepp, 2005). A protocol for ethnomedical research namely International Code for Drug Development (InterCDD) has been outlined to make the finding on ethnomedical account more reliable and such diverse methodologies have appeared in the current ethnobiological research works (Iwu & Wootton, 2002). Romney et al., (1986), Trotter & Logan, (1986), Phillips & Gentry, (1993a), Alexiades & Sheldon (1996), Schlage et al., (2000), Balasubramaniam & Murugesan (2004), Amiguet et al., (2005), Sajem and Gosai, (2006), Almeida et al., (2006), Bourbonnais-Spear et al., (2005), Ayyanar & Ignacimuthu (2005). Muthu et al., (2006), Ghorbani, (2005), Togola et al., (2005), Estomba et al., (2006), Owuor & Kisangau, (2006), Kisangau et al., (2007), and Teklehaymanot & Giday, (2007), Ragupathy et al., (2008), Mutheeswaran et al., (2011) highlighted the significance of cultural consensus methods in ethnobiological research. Jain & Rao, (1977); Prance et 12

5 al., (1987); Saklani & Jain, (1994), Rachel et al., (2003), Saslis-Lagoudakis et al., (2011) and Pieroni et al., (2011) have high-lighted some vital facts about research scope on cross cultural comparison work in quantitative ethnobotany using modern statistical tools to produce valuable research output. 2.3 Status of ethnobotanical research in India The ethnobotanical works and floristic survey of India progress hand in hand and such floristic works have greatly helped the ethnobotanists in establishing taxonomic identity of many medicinal and economic plants which in turn added to the Flora of India. The Hortus Malabaricus by Vone Rheedei in 17 th century was the first botanical work from India which contains description of plants from Malabar Coast of West India. It is a botanical treatise from India that appeared much before the publication of Linnaeus s Species Plantarum in But most of the plant species were documented in Portuguese language and not in Latin nomenclature (Manilal, 1980). Roxburgh (1832), Patriarch in Indian botany had brought out first exhaustive records on Flora of India. Roxburgh s Hortus Bengalensis compiled in 1814 contains a list of plants that were grown in Calcutta garden. He prepared about 2533 coloured illustrations of plants from Bengal and adjacent region. The Flora Indica of Roxburgh ( ) appeared in three volumes. The last two volumes were edited by William Carey and Nathenial Wallich which contains plants from different regions of India with Latin nomenclature assigned to the generic and specific name and the morphological description were done in English with few Latin words. The floristic exploration work in India gained its momentum with the establishment of Asiatic Society in 1784 and the Indian Botanic Garden near Calcutta by Robert Kyd in The herbarium of Calcutta (CAL) started around 1793 by William Roxburgh had later turned out into a world class herbarium with the contribution of Kurz (1870, 1875, 1877), Buchanan-Hamilton (1807), Wallich ( ), Griffith (1847), Clarke (1889), Prain (1903, 1905) and other botanists from the collection made from plains of Bengal and different parts of India and Bhutan (Sharma et al., 1998; Grierson, 1983, 1984, 1987, 1991, 1999, 2001 ). These herbarium collections made mostly by the Europian botanist before independent as a part of floristic exploration have also contributed in ethnobotanical data. Post independent floristic work was advanced by many Indian botanist of BSI from the mainland of the country including Thothatri (1962) from Andaman Islands that contributes understanding of ethnobotanical value of many plants particularly of 13

6 medicinal uses. Nayar et al., (1989) had reported that 1600 species of Angiosperms are medicinal plants whereas Chopra et al., (1956, 1958, 1969) has listed some 1400 species. About 1500 medicinal plants have been recorded in Wealth of India series on raw materials (Anon., ). Asholkar et al., (1992) had reported 1780 species belonging to 850 genera and that too within alphabets A-K having significant medicinal properties.the compilation work of Indian Medicinal plants by Bentley & Trimen (1880), Kirtikar & Basu (1993), Nadkarni (1996), Asholkar et al., (1992), Nadkarni (2001) have added valuable information. Works on ethnobotany focusing medicinal plants in Indian subcontinent started with the publications of Mukherjee (1953), Janaki-Amal (1956), Jain (1963a), Arora (1981), Atal & Kapur (1982), Majumdar (1988), Majumdar et al., (1978), Handa (1992), Handa et al., (1992), Pal (1992), Saklani & Jain (1994) etc. The all India Coordinated project on ethnobotany launched by Ministry of Environment and Forest Govt. of India in 1980 was an important landmark in advancement of ethnobotanical research. It has resulted in the publication of 420 research papers and 14 books on ethnobotany in India covering ethnobotanical investigation of 250 ethnic groups by Nearly 90% of these publications dealt with simple enumeration of plants and mainly focused on use of plant based traditional medicines (Rao, 1996). According to Pal (2000) based on census, 1991 over 67.8 million tribal people belonging to over 550 communities having 106 linguistic and 227 subsidiary dialects, constitute 8.08% of the population of India. They live in 5000 forest dominated villages which cover about 15% geographical area of a total 3029 million hectares of Indian landmass (8 o 4-37 o 7 N and 68 o 7-97 o 25 E). With this vastly diversified living ethnic groups and rich biological resources, India represents one of the great treasures of ethnobotanical wealth. In recent years, some notable progress has been made in the field of ethnobotanical research. With the initiative of National Institute of Science Communication and Information Resources (NISCAIR), the wealth of India raw material series has been revised thoroughly and supplemented in four volumes from (Anon., ). Earlier Maheswari (1996, 2000) had exhaustively reported the status of ethnobotanical plants in Indian sub-continents. Compendium on Indian medicinal plants edited by Rastogi and Mehrotra (1990, 1991, 1993, 1995 & 1998) had highlighted the current status of medicinal plants growing in different agroclimatic zones in India. Apart from field exploration, database work on medicinal plants has been on upward swing in the recent years with the help of advance information technology in India. Most of the 14

7 Ayurvedic importance and other medicinal plants available in Indian subcontinent has been recorded either in book form or in web-page (Billore et al., 2005). Supriya (2005), Sandhu & Singh (2005), Jain (1991, 1995, 1999), Jain & Srivastava (2001), had highlighted the manual methods and status work of Ethnobotany in India since last two decades. Jain (2004) further highlighted the objectives of ethnobotany and its significance in defining traditional knowledge while following the modern approaches. The evolution of ethnobotanical discipline had been highlighted by Schultes and Reis (1995). Ethnomedicine concept and current status in research of ethnomedicinal plants of India had been highlighted by Irfan & Khanum ( ). Further elaborative work on economic and ethnomedicinal plants in India had been reported recently by different workers in national and regional basis (Rawat and Choudhury, 1998; Pandey, 2000; Natarajan et al., 2000; Mahapatra & Panda, 2002; Harsha et al., 2003; Lalramnghinglova, 2003; Singh et al., 2003, Singh et al., 2007; Trivedi and Sharma, 2004; Panda, 2004; Farooq, 2005). 2.4 Ethnobotanical research in Northeast India The eastern Himalaya regions had been declared as 12 th global biodiversity hotspot based on number of species rarity and endemism (Myers et al., 2000). The Eastern Himalayas is located on the confluence zone of the Indo-Malalayan, Afro-tropic and Indo-Chinese biogeographical realms. The Northeastern region harbors more than 8500 species of flowering plants which constitute about 50% of India s flora of both general and ethnomedicinal importance representing 200 families out of 315 families (Mao and Hyniewta, 2000). The Northeastern region of India that comprises eight states viz. Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and Tripura harbors more than 130 major tribal communities of the total 427 tribal communities found in India (Census, 2001). In general, the tribes of North East India have been categorized into two broad ethnic communities- the Khasi and the Jaintia tribes of Meghalaya (belong to Monkhemar culture of Austric dialect) and the rest of the tribal group are basically Mongoloid (belong to Tibeto-Burman subfamily of Tibeto- Chinese group) (Grierrsson, 1909). The region exhibits one of the richest regions of the world in terms of species diversity, besides biocultural diversity. To document the floristic diversity numerous exploration works have been undertaken by various botanists. The floristic work of this region had been carried out by Hooker in The first account of regional flora of northeastern region was made by Kanjilal et al., 15

8 ( ) in flora of Assam published in 4 volumes and described about 3500 dicotyledonous woody plants from the entire region. Their report has added to the understanding of vast diversity of flora of this region. Floristic work made by other botanists after Kanjilal like Deb, 1983, 1999 (Tripura), Haridasan & Rao, 1987 and Haridasan, 1999 (Meghalaya), Balakrishnan et al., 1983 (Jowai), Chowdhery et al., 1996 (Arunachal Pradesh), Gogoi and Borthakur (1991), Rowntree (1953), Singh and Mao (1998), Baishya, 1999, Singh (1999), Hyniewta (1999) are significant one. Chauhan et al., (1996) has reported both flowering and non-flowering categories from Namdapha, Changlang and Tirap District. Choudhery et al., (1996) in their floristic account dealt with representative angiosperms families of the region. In his floristic survey of the DDBR, Choudhury (2008) documented 1004 species of angiosperms belonging to 527 genera and 124 families of which 733 species dicots and 271 species are monocots. Almost all the floristic publication has also added the uses of many species thus playing a role in ethnobotanical data. Besides these some of the specific programe have also been made in ethnobotanical studies. Notable progress in the field of ethnobotanical research have been done recently in Northeastern states such as Sinha (1986, 1996) from Manipur, Chaturvedi & Jamir (2007) from Nagaland while Rao and Murti (1990) has highlighted the status of NE region. Boissya and Majumdar (1980) reported on folklore plants of Brahmaputra valley of Assam. Saklani & Jain, (1994) highlighted some facts about research scope on cross cultural comparison work and recorded 1296 species of plants, of which 472 are reported to be used among more than one ethnic group, and 824 species are unique to a single culture from northeast India. Sharma (1999), Sharma and Boissya (2000), Sharma (2004) reported cross cultural ethnobotanical work which includes 189 species of medicinal and aromatic plants used by the Nepalese and other tribes of Assam. Borthakur (2001) in his ethnobotanical work had recorded about 1200 species from Assam which had been known for their medicinal properties and about 700 species were reported to be used by 25 odd ethnic groups in their human and veterinary healthcare system. Over 100 species occurring in Assam are known to have regular use in Ayurvedic formulations and another 75 plants in Unani and 50 species are reported to be exported from India (Borthakur, 2001; Sharma, 2004). Lalraminghimglova (2001) recorded about 400 medicinal plants from Mizoram out of these more than 200 plant species are used as ethnomedicinal plants. Chauhan (1999, 2001) had reported 650 species of ethnobotanically important plants from Sikkim Himalaya of which over

9 have medicinal uses (Anon., 2003b). The plants of medicinal and pharmacological importance of Northeast India were mostly documented by Mukherjee (2005), Chopra et al., (1958), Sinha (1996), Shukla (1993), Majumdar et al., (1978), Atal & Kapur (1982), Handa (1992), Handa et al., (1992), Shankar et al. (1993) Shankar and Rawat (1995), Saikia et al. (2006), Mao et al., (2008), Tushara et al., (2010), Shankar et al., (2012). Chetri et al., (2005) had reported 281 species of ethnomedicinal plants from Darjeeling Himalaya. Laloo et al., (2006) had reported 80 species of medicinal plants from the sacred grooves of Meghalaya. Dutta & Dutta (2005) had compiled ethnobotanical works of various investigators on some selected tribes. It had revealed 1350 species out of which 665 species of ethnobotanical importance were food plants and 899 species were used for miscellaneous purposes by about 80 tribal communities of North East India. Benniamin (2011) has reported 51 medicinally important ferns from north east India which is used traditionally to cure various ailments. 2.5 Ethnobotanical research in Arunachal Pradesh As in the other parts of India and northeast India although limited, some remarkable contributions have been made in understanding the ethnobotanical knowledge of the tribal communities. Because of the rich cultural diversity with numerous tribal communities, the state has become attraction of ethnobotanical research particularly of ethnomedicobotany.among the significant contributors Rawat & Choudhury (1998) on Nyishi and Apatani, Dam & Hajra (1997) on Monpa, Rawat and Sankar (1998) on Idu Mishmi, Yobin (1999) on Yobins, Tagin, Galo and Hill Miri tribes of Lower and Upper Subasiri District, Rawat et al., (1996), Angami et al., (2003) on Idu Mishmi, Hui & Das (2004) and Hui et al., (2004) on Hill Miri, Kala (2005), on Apatani, Gajurel et al., 2006 on Adi, Singh et al., 2007 and Namsa et al., 2011 on Monpa tribe, Das & Hui, 2006 and Sen et al., 2008 on Khampti and Goswami et al., 2009 on Tagin tribe, Kagyung et al., 2010, on Adis, Rethy et al., 2010 on Membas are found to be useful in understanding the traditional knowledge system of medicinal plants used by the various tribes of the state. All these publications have indicated the uses and importance of various species used in different way by the tribes of the state. Besides the general ethnobotany some remarkable contributions have also been made on ethnomedicobotany and medicinal plants. The work of Haridasan et al., (1990), Pandey et al., (1990), Pal (1992), Sunny et al., (1998), Pandey (1998), Bhuyan (2000), Sarmah et al., (1998, 2000), Haridasan et al., (2003), Hegde (2000, 2002), Kohli (1992), Pandey & Rawat (1993), Kagyung et al., (2010) and Khongsai et al., (2011) 17

10 have contributed a lot in documentation of healing properties numerous medicinal plants from the state. More recently Sharma & Borthakur (2008); Namsa et al., (2009), Nimachow et al., (2011), Tangjang et al., (2011), Nimasow et al., (2012), reported various medicinal plant species used by different tribes for treating different ailments from the state. After declaration as biosphere reserve in the DDBR particularly after 2000 some notable floristic and ethnobotanical works have been carried out from the DDBR. The work of Choudhury (2008) on flora, Gajurel et al., (2006), Rethy et al., (2010) on ethnobotany are found useful to understand the floristic diversity and ethnobanical importance. As a part of the present work Kagyung et al., (2010) has also highlighted on medicinal plants of DDBR. 18