Medicinal Plants

Conclusions conservation of medicinal plants habitats and indigenous technical knowledge

In conclusion we can surmise that in general the two major threats to medicinal plants are first, the loss of habitat (through land use conversion, agricultural expansion and so on) which results in the loss of both known and unknown species and second, the overexploitation of known species as a result in increased demand. Related to these two is the associated loss of indigenous knowledge and expertise. To what extent are these processes underway in Ghana The review of Ghanaian case studies...

Diversity and sustainability

For many years botanists were puzzled by the presence of certain nonessential chemical substances found within many forms of plant life. These chemicals had no apparent role within the primary production system of the plants that is, they had no clear link to the organism's growth, maintenance or regeneration. They were termed 'secondary metabolites' to distinguish them from the other, primary productive substances. These secondary substances were a puzzle because it was unclear why they would...

Prescriptions and policy implications

This section discusses some of the policies concerning the use of medicinal plants which could not only bring benefits to local people in the form of facilitating sustainable livelihoods, and provide benefits in strengthening primary health care, but could also support the conservation of biodiversity. The role of medicinal plants in sustaining livelihoods From the information available it is difficult to assess the possibilities for income generation on the basis of collection of medicinal...

Conceptions of property indigenous and modern

Vast differences exist between the property systems of Western countries and those of indigenous communities in developing countries. The property regimes of a number of industrialised countries are not homogeneous but are characterised by distinctive variations at the margin. Equally true, the regime structures of traditional communities in developing countries also reflect variations between them, and these distinctions are important to take into account when addressing conservation issues....

The current role of ethnobotany

As the complexities and relevance of ethnobotany gain a broader audience, its applications have reached beyond the documentation of a new therapy or fiber to provide models and incentives for cultural and biological conservation. Long-term experience with plant biology, habitat preference and regenerative capacity can provide useful models for a balance between the use and conservation of resources (Redford and Padoch, 1992). Cultural experience provides a living link to complex natural...

Biotics

Biotics Ltd is a private, UK-registered company founded in 1983. Its efforts to supply the pharmaceutical industry with biotic samples began in 1986 as a result of a European Community initiative on biotechnology which provided funding for Biotic's initial activities in this area. The phytochemicals program at Biotics has developed largely over the past 4 years. In November 1990, Biotics launched Bio-Ex, a commercial extraction facility and is currently promoting an investment proposal to...

The National Biodiversity Institute of Costa Rica

In an arrangement signed on 19 September 1991 with the US pharmaceutical company Merck & Co., INBio agreed to provide Merck & Co. with plant, insect and environmental samples in exchange for over 1 million. In addition, Merck & Co. agreed to pay royalties on any products developed from the Costa Rican samples provided by INBio. What does the INBio-Merck & Co. arrangement and the INBio experience in general imply about the prospects for biodiversity-rich countries developing...

Medicinal Plants Of Introduction

The value of biodiversity as a source of pharmaceutically active substances has been the subject of a number of studies, for example Pearce and Puroshothaman (this volume), McNeely (1988), Farnsworth and Soejarto (1985) and Principe (1991). This value is now being cited as one of the many arguments for conserving natural habitats and, in particular, tropical forests which contain the largest number of plant species. These analyses, however, ignore the additional role of these as sources of...

Health care pharmaceuticals and plants

The demand for new drugs and, therefore, for the product of pharmaceutical R& D originates in the health care market. This is true regardless of the method of drug development and whether the drug is a synthetic or natural compound. Ethical pharmaceuticals are just one method of treating ill health.1 Surgery, irradiation treatment, manipulation of diet and lifestyle, herbal medicines, physiotherapy, faith healing, etc. are all active means of providing health care to those whose lives are...

The role of secondary compounds in plants

The first secondary compounds to be characterised were those accumulating in relatively high concentration and this led to the view that they were probably 'excretory products' or 'end products of metabolism'. They were thus described by Czapek in the second edition of his 1921 textbook Plant Biochemistry and this view persisted into the 1970s. An alternative to the 'waste product' hypothesis was that the synthesis of secondary metabolites provides a way of 'using up' primary metabolites to...

The decline of diversity

Biological diversity is the product of the evolutionary process and it is in decline because of a relatively recent change in the hands that are on the controls. For millions of years the allocation of resources between competing life forms was accomplished by the evolutionary process in accord with the metric of relative fitness. Now the allocation of the resources necessary for survival is determined not by nature but by human societies. For whatever reason, humans have been able to usurp...

Conclusions

First, it discussed the rapid rise in interest in medicinal biodiversity found predominantly in developing countries. Both fear and economic fortune enter the calculus of policymakers and industrialists in developed countries with regard to biodiversity conservation. I also explored the salient differences between Western and traditional systems of property. It is evident, though, that the property system of industrialised countries is being forced on the...

Indigenous discovery and utilization

We have selected a few examples of the complex convergences of biology, ingenuity, faith and circumstance that have led to discoveries of new species and new applications. Although this volume primarily focuses on plants and natural products that are used medicinally, we have also included several foods in this section to help illustrate the chemical sophistication of ethnobotanical information in some cases, and its surprising familiarity in others. At some point in the history of human...

The development of ethnobotany through the prism of academia

Although all the academic twists and turns of this interdisciplinary and applied science are not relevant to this discussion, it is important to sketch the changing perspectives on indigenous knowledge as a backdrop for current attitudes and applications. The direct dependence on plants has historically given the knowledge of how to identify and utilize individual species a place of central importance, but as markets grow, many people have become removed from a personal stake in this...

Why preserve the chemical diversity of plants

The chemical industry seeks novel, single active molecules which can preferably be synthesised in a laboratory. The evolutionary pressure on plants has apparently caused them to maintain an arsenal of strategically useful compounds which can be varied in response to changing ecological pressures. These needs have been met by mixtures of metabolically-related variants on particular skeletal themes, frequently complex and only isolated or synthesised with difficulty. The observed activity of...

The role of ethnobotany in pharmaceutical prospecting

Plants have been the cornerstone of medicinal therapies for thousands of years and continue to be an essential part of health care for much of the world. The traditional origins of many current pharmaceuticals have been obscured by the process of drug development, such as aspirin from willow bark (Salix spp.), reserpine for hypertension from the Indian Snake Root (Rauwolfia serpentina) and D-tubocurarine, widely used as a muscle relaxant in surgery, from arrow poisons (Chondodendron tomentosum,...

Medicinal chemistry screening and rational design

Folk medicine often attributed apparent therapeutic properties of plants to their shapes and habitats. For instance, the bark of Salix alba, the willow tree, which grows in damp environments, was used to treat the aches and fevers that one could catch in such places. But its properties and those of many other traditional medicines were real. The analgesic and antipyretic component of the willow bark, salicin ( ), was isolated in 1829, converted by the middle of the century to salicylic acid (2)...

Introduction

In recent years, genetic resources have increasingly been brought under the spell of intellectual property rights, as conceived in the industrialised countries. The unique property regimes enjoyed by traditional communities in many developing countries have been sidelined in favour of Western-derived patent systems. With a widening interest in medicinal biodiversity, the developing countries are likely to derive little or no benefits from their biotic heritage after years of conservation. The...

The structural range of plant secondary metabolites

A full description of the range of plant compounds is outside the scope of this chapter but may be found in a number of recent texts such as Mann (1987) and Luckner (1990). An overview of those classes most commonly found is presented here. The dividing line between primary and secondary metabolism is unclear. The two are connected in that primary metabolites provide the starting material for secondary metabolites which are largely formed from three principal starting materials (Mann, 1987) 1....

The origin and evolution of plant secondary compounds

The history of life can be divided roughly into two equal parts the age of bacteria (3500-1700 million years bp) and the age of eukaryotes (1700 million years bp till present). The origin of the nucleated cell, which allowed more sophisticated control of cellular function, enabled the development of the complex multicellular organisms seen today. Secondary chemicals are produced in greatest abundance by microorganisms in crowded conditions and by plants, fungi and sessile animals, such as...

Plant chemicals in the evolution of mammals and humans

The relation between primates and fleshy fruits was established in the early-mid Eocene (55 to 48 million years bp) when the tropical forests reached their maximum latitudinal extent (Collinson and Hooker, 1991). Plants have formed a significant part of the diet throughout human evolution and there can be no doubt that a wide range of plant chemicals was thereby ingested. Although there is evidence to suggest that the evolution of plant secondary compounds was closely influenced by their...

Secondary compounds and genetic diversity

The secondary metabolites of plants are one manifestation of genetic diversity. Although the metabolic pathways leading to the commoner plant secondary compounds are known, very little is known about the control of the expression of these pathways. The absence of the expression of any pathway cannot be taken to indicate that the necessary genes are absent, and it is not possible to know what genetic potential is being lost when any species is driven to extinction. Bradshaw (1991) recalls the...

NCI Plant Screening Program Phase II 1986present3

In 1986, NCI initiated three 5-year contracts for a renewed plant collection program with the Missouri Botanical Garden, the New York Botanical Garden (NYBG) and the University of Illinois. The initial contracts totaled 2.7 million and the contracts were reawarded for a further 5 years to the incumbents in September 1991. Each collecting institution is currently responsible for collecting 1500 samples of 0.3-1.0 kg (dry weight) per year plus voucher samples. One of the voucher samples must be...

Intellectual property laws

Intellectual Property Rights (IPRs) are a particular aspect of property covering 'all things which emanate from the exercise of the human brain' (Philips and Firth, 1990). The major intellectual property rights are patents, plant breeding rights, trade secrets, trade marks and copyright. The general principle behind IPR protection is that the 'right holder' is given some form of monopoly control over the economic exploitation of the material concerned. The over-riding economic justification...

Methods of drug development

Austel and Kutter (1980) suggest that there are three methods for obtaining lead compounds or chemical structures for drug development by reference to compounds and structures that are known to demonstrate activity relative to the disease target, by random screening of compounds and structures - the 'empirical' approach, and by utilizing knowledge of the biomolecular processes that play an important role in disease - 'rational' drug design. Two major sources of leads that are based on known...

The US National Cancer Institutes plant screening program

In 1937, the US NCI was founded in order to initiate and coordinate research related to cancer. In 1955, the NCI created the Cancer Chemotherapy National Service Center (CCNSC) with the aim of developing a program of screening chemical substances for anti-cancer activity. Initially envisioned as a voluntary cooperative cancer chemotherapy program, the CCNSC has gradually grown into a major drug research and development unit. CCNSC (now incorporated into NCI's Developmental Therapeutics Program)...

NCI Plant Screening Program Phase I 195582

The screening of plants did not begin in a major way until 1960 when NCI reached an agreement with the US Department of Agriculture (USDA) for the annual collection of large numbers of plant samples. Starting with the US and Mexico, the USDA and other subcontractors scoured 60 countries for plant samples during the first phase of the NCI natural products program. By the end of the first phase, Suffness and Douros (1979) estimated that NCI was receiving about 35CKMOOO plant samples a year, of...

Conclusion an introduction to this volume

The remainder of this volume provides the details of the argument presented here. In short, the volume was constructed by requesting a series of eminent scholars to address the salient points concerning plant communities, pharmaceutical production, intellectual property rights and biodiversity conservation, each from the perspective of his or her own field of specialisation (botany, ethnobotany, chemistry, economics, law and policy). Part A presents the botanical and ethnobotanical basis for...

Secondary plant metabolites and the chemical industry

The first secondary compound to be isolated in a pure form was morphine from the opium poppy, in the early nineteenth century. Although it took almost 50 years for its structure to be elucidated, this nevertheless signalled the beginning of pharmacy as an exact science of fully characterised molecules given in regulated doses. The techniques of isolation, characterisation and synthesis gradually improved during the nineteenth century, and gave rise to a modern chemical industry based not on...

An overview of pharmaceutical research and development

Real global expenditures on pharmaceutical R&D began rising substantially in the 1980s and nowhere more dramatically than in the USA where R&D spending was doubled during the 5-year period from 1986 to 1990. In 1992, the US Pharmaceutical Manufacturers Association predicted that US companies would invest close to 11 billion in R&D (PMA, 1992). Investment in pharmaceutical R&D is not without its rewards. The global market for pharmaceuticals was estimated to be 150 billion in 1991. More than 70...

Plants and medicine

Plant species are used for medicines in two ways (1) as a major commercial use, whether by prescription or over-the-counter sales, and (2) as traditional medicines which may or may not attract a market price. In the rich world, perhaps 25 of all medical drugs are 'based' directly on plants and plant derivatives this means that they remain linked directly to those plant forms for their production. In the poor world the proportion of drugs based on plants is closer to 75 (Principe, 1991)....

A model of economic valuation of medicinal plants

We are now in a position to develop a simple model for determining the medicinal plant value of a unit of land as biodiversity support. The approach is fraught with difficulties given the considerable data deficiencies, but it is worth pursuing. For any given area, say a hectare, there will be some probability, p, that the biodiversity 'supported' be that land will yield a successful plant-based drug D. Let the value of this drug be Vt(D), where subscript i indicates one of two ways of...

Conclusion

Overall, then, despite the formidable data problems and the difficulties involved, the model used here does produce a very concrete estimate of the contribution of the global tropical forests to the production of plant-based drugs this value lies in a range from very low to around 20 per hectare. These values relate to the species 'at risk'. Clearly, the actual values must be higher as the loss of very large tracts of tropical forest would place many other plant species at risk. We therefore...

Biodiversity conservation in perspective

In view of the increasing importance attached to tropical medicinal plants by multinational corporations and some research organisations in industrialised countries, many species face the danger of extinction or disappearance from unscrupulous overharvesting. This threat is very real as evidenced by reported losses of some species in recent times. Most of the depletions are not natural but are a consequence of the heightened interest in screening medicinal plants, largely identified by...

Information dispersal and perpetuation

The key to the quality and vitality of ethnobotanical information is not the static end result, but the biological and cultural dynamic that fuels a cycle of discovery, use and proliferation (Johns, 1990). Ethnobotany, like most scientific endeavors, is perpetually adapting old ideas to new information, but few fields are losing their resource bases as quickly. Ethnobotanical knowledge is rapidly eroding, caught between the loss of species and the habitat that provide new material on the one...

The appropriation of the value of biological diversity

The problem of appropriating international flows of wholly intangible services has been recognised and addressed for over 100 years. The very first truly international convention, the Paris Patent Union, was on precisely this subject it attempted to create in 1868 an international mechanism for repatriating compensation to those who invested to generate information. Since that time a very substantial body of national and international law has developed around the idea of generating such flows,...

The economic value of plantbased drugs

Ideally, what is required for economic valuation purposes is some idea of the ruling prices for plant genetic material and elasticities of demand by drug companies for that material. Given the availability of synthetic substitution as an alternative technology for some drugs, it seems clear that the demand elasticity will be high for those drugs, but fairly low for plant-based material that cannot, so far anyway, be synthesised. Drug companies today tend to use specialist plant gathering...

Patent frauds the odds are stacked against developing countries

In more recent times, an indigenous plant in Ethiopia that has been used for generations in a variety of ways has suddenly become a subject of patent protection in industrialised countries. The story of endod rings in our minds with piercing familiarity as many other cases occur of indigenous plants suddenly becoming the property of firms or other institutions in industrialised countries. The specific and generic uses of some plants have been known in indigenous communities for years, but this...

Acknowledgements

This book is the result of a project on intellectual property rights and biodiversity conservation sponsored by the Centre for Social and Economic Research on the Global Environment, directed by Professors David Pearce and Kerry Turner. The ESRC's sponsorship of the centre and the project are gratefully acknowledged. The editor would like to acknowledge his personal debts to Professor David Pearce who (as director of CSERGE) was involved in commissioning this project and has been supportive...

The supply of plants for random screening programs

The use of plants in random screening must always involve a limited initial collection of material whether from an in-situ or ex-situ site. Depending on the success of the original sample a number of subsequent re-collections of much larger size may be necessary. McChesney (1992) suggests some numbers for the amounts of dried plant material necessary for completion of the following stages of drug development and marketing initial screening and isolation of lead compound 5 kg of dried material,...

What is a secondary compound

The concept of 'secondary' chemicals was first introduced in the 1890s to mean those which were not deemed necessary for the life of the plant. There was some experimental support for this view Pfeffer (1897) precipitated the tannins of Spirogyra with methylene blue and showed that the organism continued to grow. Bonner and Galston (1952) referred to the secondary products as 'chemical substances which are not essential to the economy of the plant and which have no recognisable role in...

Biodiversity the rising interest

The abrupt surge of interest in biodiversity among research institutions and governments in industrialised countries stems from two fundamental considerations. One is based on fear and the other is grounded on economic fortune. The aspect of fear arises from the fact that deforestation and the destruction of biodiversity in the developing countries is most certainly going to destroy the world's greatest carbon sinks. In a sense, developing countries are now seen as the vital lungs of the...

Preserving biodiversity the role of property rights

The accelerating depletion of our natural resources can be expressed along a continuum from species to individual segments of functional genetic code. It is the potential value of the genetic material that is at the core of our attempt to preserve biodiversity the preservation of genetic material which has, as yet, undiscovered beneficial properties. Increasingly it has been recognised within the environmental community that one necessary approach to encouraging nations to preserve their...

The pharmaceutical discovery process

Pharmaceutical research has become a highly rational although still developing science. In the course of a few decades, preparing plant extracts has been replaced by biophysical measurements, computer modeling of protein and drug molecules, and biotechnology. In recent years, however, ethnomedicine and tropical biodiversity are being proposed as alternative sources of badly needed or, as some believe, safer drugs. In this chapter we bridge the communication gap between the specialist and the...