Traditional medicine is the synthesis of the therapeutic experience of generations of practitioners of indigenous medical systems. In the history of mankind, many infectious diseases have been treated with herbs. There is a growing demand for traditional medicine through traditional healers and herbalists in the treatment of infectious diseases. Among the treatments used, plant medicines form an important part. Many scientific investigations have highlighted the importance and contribution of many plant families i.e. Asteraceae, Liliaceae, Apocynaceae, Solanaceae, Caesalpinaceae, Rutaceae, Piperaceae, Sapotaceae used as medicinal plants. Medicinal plants play an important role for the development of new drugs (export and import of various parts or bioactive compounds in the current market). Bioactive extracts should be standardized based on the active compound. Bioactive extracts should undergo limited safety studies.
Introduction
India is one of the 12 mega biodiversity centers with 45,000 plant species; Its diversity is unmatched due to 16 different agricultural claim zones, 10 vegetation zones and 15 biological provinces. The country has rich floral diversity.Floral Diversity in India.
Number Species
15,000 - 18,000 Flowering Plants
23,000 Fungi
25,000 Algae
1,600 Lichens
1,800 Bryophytes
30 million Microorganisms
Traditional medicine is the synthesis of the therapeutic experience of generations of practitioners of indigenous medical systems. Traditional preparations include medicinal plants, minerals and organic substances etc. Herbal medicine includes only those traditional medicines that primarily use medicinal plant preparations for therapy. Ancient records evidence their use by the Indians, Chinese, Egyptians, Greeks, Romans and Syrians dating back about 5000 years (Table 2). About 500 plants with medicinal uses are mentioned in ancient texts and about 800 plants have been used in indigenous medical systems. The Indian subcontinent is a vast repository of medicinal plants used in traditional medical treatments (Chopra et al., 1956), which is also a rich source of knowledge (Nadkarni, 1982; Zone, 1984). Various indigenous systems like Siddha, Ayurveda, Unani and Allopathy use many plant species to treat various diseases (Reb and Staden, 1997). About 20,000 medicinal plant species have been recorded recently in India (Dev, 1997), but more than 500 traditional communities use about 800 plant species to treat various diseases (Kamboj, 2000). Currently 80% of the world's population depends on plant-derived medicine for the first line of primary health care for human relief as it has no side effects (Veale et al., 1992). Plants are important sources of medicines and currently about 25% of pharmaceutical prescriptions in the United States contain at least one plant-derived ingredient. In the last century, about 121 pharmaceutical products were prepared based on traditional knowledge obtained from various sources (Anesini and Perez, 1993).
Modern Medicines from Higher Plants
Medicinal plants play a vital role in the development of new drugs. During 1950-1970 about 100 plant based new drugs were introduced in the drug market of the United States of America including deserpidine, resinemine, reserpine, vinblastine and vincristine which are derived from higher plants. From 1971 to 1990 new drugs like ectoposide, E guggulsterone, teniposide, nabilone, planotol, Z-guggulsterone, lectinan, artemisinin and ginkgolides emerged worldwide. From 1991 to 1995 2% drugs were introduced which include paclitaxel, topotecan, gomishine, irinotecan etc. Plant based drugs provide outstanding contribution to modern medical science; For example: Serpentine, isolated from the root of the Indian plant Rauwolfia serpentina in 1953, was a revolutionary event in the treatment of hypertension and lowering blood pressure. Vinblastine isolated from Catharanthus roseus (Farnsworth and Blaster, 1967) is used for the treatment of Nature Preceding: Hodgkin's, choriocarcinoma, non-Hodgkin's lymphoma, leukemia in children, testicular and neck cancer. Vincristine is recommended for advanced stages of childhood acute lymphocytic leukemia, Hodgkin's, lymphosarcoma, small cell lung, cervical and breast cancer. (Farnsworth and Bingel, 1977). Phophyllotoxin is a component of Phodophyllum emodi currently used against testicular, small cell lung cancer and lymphoma. The Indian native tree Nothapodytes pneumonia (Mappia foetida) is mostly used for the treatment of cervical cancer in Japan.Plant derived drugs are used to treat mental illness, skin diseases, tuberculosis, diabetes, jaundice, hypertension and cancer. Medicinal plants play a vital role in the development of potent therapeutic agents. Plant derived drugs came into use in modern medicine through the use of plant materials as indigenous cures in folklore or traditional systems of medicine. More than 64 plants have been found to have significant antibacterial properties; and more than 24 plants have been found to have antidiabetic properties (Archmon et al., 1980), Antimicrobial studies of plants (Perumal Sami and Ignacimuthu, 1998; 1999 and Perumal Sami et al., 2006), Plants for antidote activity - Inactivation of russelii and Naja kaouthia poison by Daboia lupeol acetate from root extract of Indian Sarsaparilla Hemidesmus indicus R.Br. (Chatterjee, et al., 2006). which effectively neutralized the pathophysiological changes induced by Daboia russelii venom (Alam et al., 1994).
The present investigation explores the isolation and purification of another active compound from the methanolic root extract of Hemidesmus indicus, which was responsible for neutralizing snake venom. Both the antioxidant property of the active compound against viper and cobra venom and antiserum action potentiation were studied in experimental animals. For the development of plant derived therapeutic antagonists against snakebite for the needy community, further attention needs to be paid to the mechanism of action of toxin neutralization induced by plant derived micromolecules. However, toxicity of plants has been known for a long time, and the history of these poisonous plants along with medicinal plants is very old and popular all over the world, they are considered as the major natural source of folk medicine and detoxification. Recent chemical synthesis of the active components contained in these plants (Adelkan and Gautaman, 2001; Heinrich, 2000; Pfister et al., 2002).
Ethnopharmaceuticals and traditional modern medicine derived from plants
1. Codeine, Morphine Opium, latex of Papaver somniferum, used by ancient Sumerians. Egyptians and Greeks for treatment of headache, rheumatism and to induce sleep.2. Atropine, Hyoscyamine Atropa belladonna, Hyoscyamus niger etc., were important drugs in Babylonian folklore.
3. Ephedrine Crude drug (astringent yellow) obtained from Ephedra sinica has been used by Chinese people since 2700 BC for respiratory diseases.
4. Quinine Cinchona spp. was used by Peruvian Indians to treat fever
5. Emetine Brazilian Indians and many other South American tribes used the root and rhizomes of Cephalis spp. to induce vomiting and cure dysentery.
6. Colchicine The use of Colchicum in the treatment of gout has been known in Europe since 78 A.D.
7. Digoxin The leaves of digitalis were being used in cardiac therapy in Europe during the 18th century.
Some important medicinal plants used for major modern drugs for cancer
Plant Name1) Catharanthus roseus L. (Apocynaceae)
2) Podophyllum emodi Wall. (Beriberidaceae)
3) Taxus brevifolius (Taxaceae)
4) Maphea foetida Miers.
5) Comptotheca acuminate
6) Juniperus communis L. (Cupressaceae)
Drugs
1) Vinblastine and Vincristine
2) Podophyllotaxin,
3) Paciltaxel, Taxotere
4) Comptothecin, Larnotecan and Topotecan
5) Quinoline and Comptothecin Alkaloids
6) Teniposide and Etoposide
Treatment
1) Hodgkin's, lymphosarcoma and leukemia in children.
2) Testicular cancer, small cell lung cancer and lymphoma.
3) Ovarian cancer, lung cancer and malignant melanoma.
4) Lung, ovarian and cervical cancer.
5) Used to treat cervical cancer in Japan
6) Lung cancer
Teniposide and etoposide isolated from Podophyllum species are used for testicular and lung cancer. Taxol isolated from Taxus brevifolius is used to treat metastatic ovarian cancer and lung cancer. The above drugs came into use through screening studies of medicinal plants as they showed fewer side effects, were cost effective and had better compatibility.
Market potential of phytomedicines
Total phytomedicine sales reported in the European Union by country were estimated at about US$ 6 billion in 1991 and US$ 4 billion in 1996, of which almost half was sold in Germany at $3 billion, France at $1.6 billion, Italy at $0.6 billion and Japan at $1.5 billion. The current global market is reported to be US$ 250 billion (Brauer et al., 1998). Total herbal product sales in India are estimated at $1 billion and exports Nature Precedent: herbal crude extracts are about $80 million, of which 50% is contributed by Ayurvedic classical preparations. Plant-derived medicines are important in Germany and Russia. In particular, herbal medicines are imported by many countries for use in traditional medicinal preparations from different parts of the country.Role of World Health Organization (WHO) in Phytomedicine Therapy
In 1991 WHO developed guidelines for the evaluation of herbal medicine, and the same year the Sixth International Conference of Drug Regulatory Authorities held in Ottawa ratified it. The main features of the WHO guidelines are: 1). Quality assessment: Raw plant material or extracts, plant preparations and finished products. 2). Stability: Shelf life. 3). Safety assessment: Documentation of safety based on experience .Assessment of efficacy: Documented evidence of traditional use and activity determination (animal and human).Standardization of Phytomedicines
In the traditional system of medicine, drugs are delivered mainly in the form of aqueous or ethanol extracts. Fresh plant juice or crude extracts are rare rather than a rule. Medicinal plants should be authentic and free from harmful materials such as pesticides, heavy metals and microbial and radioactive contamination. The medicinal plant should be subjected to one-time or repeated single solvent extraction or aqueous extraction or as described in ancient texts. The extracts should then be checked for biological activity in experimental animal models.New sources of tribal medicine for future investigation
Tribal healers in most countries, where ethnomedical treatments are frequently used to treat cuts, skin infections, inflammation, ageing, mental illness, cancer, asthma, diabetes, jaundice, scabies, eczema, venereal diseases, snakebite and gastric ulcers, instruct local people how to prepare medicine from herbals (Pushpangadan and Atal, 1984; Waller, 1993; Perumal Sami and Ignasimuthu, 1998-1999; Perumal Sami et al., 2006). They do not keep any records and the information is passed on mainly orally from generation to generation (Dhar et al., 1973; Sophowara, 1982). The World Health Organization (WHO) has shown great interest in documenting the use of medicinal plants used by tribals of different parts of the world (Cado et al., 1987). Many developing countries have intensified their efforts in documenting ethnobotanical data on medicinal plants. Research has been intensified to find scientific evidence for the claims of tribal healers on Indian herbs. Once these local ethnobotanical preparations are scientifically evaluated and properly disseminated, people will get better information about efficacious drug treatments and improved health status (Manandhar, 1987).Conclusion
Determining the biological (activity) properties of plants used in traditional medicine is helpful for rural communities and informal settlements. Many authors are currently working on isolating active compounds by bioassay-guided fractionation from species showing high biological activity during screening. Therefore, these scientific investigations can be used to develop drugs for these diseases. Further research is necessary to isolate the compounds responsible for the observed biological activity.
Tags:
MEDICINAL PLANTS & HERBS
