Industrial utilization of medicinal plants in developing countries

Industrial utilization of medicinal plants in developing countries

Tuley De Silva

Chemical Industries Branch
Industrial Sectors and Environment Division
United Nations Industrial Development Organization
P O Box 300
A-1400 Vienna, Austria
Fax: ++43 1 232156 Email: TDE-SILVA@unido.org

Abstract

The majority of the rural people in developing countries use plant based traditional medicines for health care. These are still produced using age old methods which can affect their quality, stability and efficacy. Resurgence of interest in green products in the industrialised countries has created an expanding market for plant based products that could be produced by developing countries to be competitive provided the quality and safety specifications could be satisfied. The constraints for the development of such industries in developing countries and the requirements for overcoming these have been identified. The possibilities for value addition, processing and product improvement, and technical assistance needs of developing countries for the industrial utilization of medicinal plants are indicated.

Introduction

Most developing countries are endowed with vast resources of medicinal and aromatic plants. These plants have been used over the millennia for human welfare in the promotion of health and as drugs and fragrance materials. This close relationship between man and his environment continues even today as a large proportion of people in developing countries still live in rural areas. Furthermore, these people are precluded from the luxury of access to modern therapy, mainly for economic reasons.

About 80% of the population of many developing countries still use traditional medicines for their health care. Modern pharmacopoeia still contain at least 25% drugs derived from plants and many others which are synthetic analogues built on prototype compounds isolated from plants. China, India, Sri Lanka and a few other countries have officially recognized the use of traditional medicines in their health care delivery systems.

A major factor impeding the development of the medicinal plant based industries in developing countries has been the lack of information on the social and economic benefits that could be derived from the industrial utilization of medicinal plants. Except for the use of these plants for local health care needs, not much information has been available on their market potential and trading possibilities. As a result, the real potential of these plants has not been exploited by the governments or entrepreneurs.

The demands of the majority of the people in developing countries for medicinal plants have been met by indiscriminate harvesting of spontaneous flora including those in forests. As a result many plant species have become extinct and some are endangered. It is therefore necessary that systematic cultivation of medicinal plants be introduced in order to conserve biodiversity and protect threatened species. Systematic cultivation of these plants could only be initiated if there is a continuous demand for the raw materials. It is therefore necessary to establish processing facilities preferably in the vicinity of cultivations in order to create a demand and assure farmers of the sale of raw material. Thus cultivation and processing should be started simultaneously. In cases where parts of mature plants from forests are to be harvested, sustainable harvesting techniques are needed to protect these plants.

The promotion and development of processing of plant-based products have been given a fresh impetus due to certain ground realities:

- Green consumerism and the current resurgence of interest in the use of "Naturals" in developed countries.- Free market economy bringing in more openness and expanding markets and demand for new resources, materials and products.
- A growing acceptability of the social responsibility of minimizing socio-economic inequalities in favour of rural people resulting in creating additional job and income opportunities for poor people.
- Poor economic conditions in developing countries restricting import, thereby placing increased reliance on medicines using local plant resources.
- Increasing awareness regarding biodiversity conservation and the sustainable and protective use of plant resources.
- Search for new phytopharmaceuticals for the prevention and cure of deadly diseases such as cancer and AIDS.

In 1981, the United Nations Industrial Development Organization (UNIDO) established a programme for the systematic utilization of this renewable natural resource for the benefit of the populace of developing countries. The programme aims for initiating development projects for increasing the industrial output of developing countries in the field of locally-used herbal drugs and phytopharmaceuticals which affect the economies of both developing and developed countries.

Some of the constraints associated with the processing of medicinal plants which may result in reducing their competitiveness in global markets and which have to be remedied are:

- Poor agricultural practices
- Poor harvesting (indiscriminate) and post-harvest treatment practices
- Lack of research on development of high-yielding varieties, domestication etc.
- Poor propagation methods
- Inefficient processing techniques leading to low yields and poor quality products
- Poor quality control procedures
- High energy losses during processing
- Lack of current good manufacturing practices
- Lack of R & D on product and process development
- Difficulties in marketing
- Lack of local market for primary processed products
- Lack of trained personnel and equipment
- Lack of facilities to fabricate equipment locally
- Lack of access to latest technological and market information

Systematic cultivation of many medicinal plants needs specific cultural practices and agronomical requirements. These are species-specific and are not only dependent on soil, water and climatic conditions. Hence research and development work has to be done to formulate Good Agricultural Practices which will include proper selection and identification, propagation methods, cultivation techniques, harvesting, step-wise quality control of raw material up to processing stage, post-harvest treatment, storage and safety. These aspects have to be incorporated into protocols for the cultivation of medicinal plants.

Organic farming is another practice that is gaining wide acceptance as world demand particularly in developed countries for organically grown crops is rapidly on the increase. Farmers have to be trained in all aspects of organic farming of medicinal plants and herbs including obtaining certification from associations that do the monitoring starting from cultivation to final harvesting. Organic farming which is labour-intensive gives the developing countries the comparative advantage to be competitive.

Process technology

Traditional medicines - Modern technology

The medicines for internal use prepared in the traditional manner involve simple methods such as hot- or cold-water extraction, expression of juice after crushing, powdering of dried material, formulation of powder into pastes via such a vehicle as water, oil or honey, and even fermentation after adding a sugar source. The range of products that could be obtained from medicinal plants is given in Figure 1.

Traditional herbal medicines were produced using age old methods by the practitioner him/herself who was able to identify the correct plant species. This practice of the traditional practitioner dispensing his own medicines is being gradually shifted to herbal drug stores which are profit-oriented. As a result, there is no guarantee of the authenticity and quantity of plant material used in the preparations. The quality of traditional medicines so produced vary widely and may not even be effective. Therefore, there is a need to select proper and appropriate technologies for the industrial production of traditional medicines such that the effectiveness of the preparation is maintained. Traditional methods used have many disadvantages which could be corrected by selecting the suitable technologies. It has to be stated that the traditional methods were dependent on the status of technology that was available at that time. It therefore follows that these can be modified and improved using the technologies available today to make them more effective, stable, reproducible, controlled and in dosage forms that can easily be transported or taken to office.

Hence the introduction of appropriate, simple and low-cost technologies should be encouraged maintaining as much as possible the labour-intensive nature of such activities,

Figure 1: Industrial uses of Medicinal Plants

conservation of biodiversity through small-scale production and preservation of cultural knowledge. Use of sophisticated modern technology will alienate the traditional practitioner as he has no control over such production methods. Even in the use of appropriate technologies, the practitioner who produces these drugs has to be educated about the advantages of using such production and quality control methods.

One major concern in introducing modern technology for the production of traditional medicines is whether the final preparation will be acceptable to the practitioner who has sole faith in extemporaneous preparations. This problem has to be overcome by a process of education, whereby the disadvantages of the old methods and the advantages of the new methods can be imparted.

Value added products

The value of medicinal plants as a source of foreign exchange for developing countries depends on the use of those plants as raw materials in the pharmaceutical industry. These raw materials are used to:

- Isolate pure active compounds for formulation into drugs (quinine, reserpine,digoxin,etc.)
- Isolate intermediates for the production of semi-synthetic drugs
- Prepare standardised galenicals (extracts, powders, tinctures, etc.)

If one is to produce known pure phytopharmaceuticals used in modern medicine, more processing stages and more sophisticated machinery are required. Furthermore, safety and pollution aspects have to be considered. Most of these processes and formulations are patent-protected. Even transferring technology through contractual agreements and payment will not be of much help unless there is a large local demand for these drugs. Often the drugs so produced are more expensive than world market prices owing to the limitations of the economy of scale of production.

Certain plants are rich sources of intermediates used in the production of drugs. The primary processing of parts of plants containing the intermediates could be carried out in the country of origin thus retaining some value of the resource material. For example, diosgenin (from Dioscorea sp.) and hecogenin (from sisal) used in the production of steroids can be commercially produced in the countries of origin where there are steady supplies of sufficient raw materials.

Processed products (galenicals) from plants could be standardised fluid/solid extracts or powders or tinctures. Standardised extracts of many plants (e.g. Aloe species, Atropa belladonna,Cassia angustifolia, Capsicum annuum, Centella asiatica, Cephaelis ipecacuanha, Digitalis species, Commiphora mukul, Panax ginseng) are widely used in health care. Some of these have to be formulated for incorporation into modern dosage forms. New formulations require some development work, particularly on account of the nature of the processed products. Plant extracts are difficult to granulate, sensitive to moisture and prone to microbial contamination. Hence the types of excipients to be used and the processing parameters have to be determined.

Downstream processing activities leading to different medicinal plant based products are indicated in Figure. 2.

Most of the activities of UNIDO in the industrial utilization of medicinal plants have involved: the production of standardised traditional medicines, galenicals and extracts, the formulation and development of dosage forms, the development of new preparations based on the traditional pharmacopoeia, research and development in processing and formulation and basic chemical and pharmacological studies. Processing using clean and pollution free technologies have been introduced.

Pilot scale production

Development of process parameters has to be carried out at a pilot scale in order to be upscaled to industrial production. Many R&D institutions and universities in developing countries do not have such facilities and are therefore unable to pass on their R&D findings to the industry. UNIDO has played a significant role in achieving university-industry interaction by designing a polyvalent pilot plant which could be used for many unit operations needed for the production of plant-based products. Detailed engineering drawings with specifications and bills of quantities are published in a separate UNIDO publication (UNIDO, 1991). The pilot plant has enabled the R & D work to be demonstrated to produce final products which could be market tested. Universities in turn have been able to realize the hidden potential of industrialization of their R & D work. Any institution which wants to initiate downstream processing of medicinal plants and other non-wood forest products should possess facilities for pilot scale production.

New technologies

Improved methods for the processing of medicinal and aromatic plants and new techniques for quality assessment are being developed rapidly and continuously and they have to be introduced to developing countries if they are to forge ahead to keep up with recent developments and new international requirements. One such method of recent development is Supercritical Fluid Extraction of natural products as an alternative for solvent extraction. It is now used both for processing of phytopharmaceuticals and other plant products and for the removal of trace amounts of contaminant substances such as pesticides, toxins and surfactants.

Quality assurance

The control of the quality of the raw materials, finished products and of processes is an absolute necessity, if one is to produce goods for world markets and human consumption.

International Standard Specifications exist for some processed products and some countries and buyers have their own requirements. The quality requirements for medicinal plant preparations are stringent in terms of content of active principles and toxic materials. Whereas the production of traditional medicines for local use does not require such stringent standards, what is produced will be a much more improved version of the already produced medicines using traditional methods.
 

Figure 2: Downstream processes

Quality has to be built into the whole process beginning from the selection of propagation material to the final product reaching the consumer. It is therefore a management system where all steps involved in the industrial utilization process have to be properly and strictly controlled to produce the desired quality products. All elements of Total Quality Management(TQM) have to be introduced in any industrial project. The requirements for ISO 9000 certification and Good Manufacturing Practices(GMP) have to be introduced and the personnel trained so that enterprises could introduce the proper systems needed for certification. Furthermore eco-audit procedures (ISO 14000) leading to eco-labelling will be required for safeguarding environmental damage.

Human resource development

Many developing countries have a core of trained personnel in the fields of chemistry, biology, agriculture, pharmacology and pharmacy: They lack resources in such fields as chemical engineering and technology. This can be considered as a major constraint upon industrial development. UNIDO therefore has developed the human resources required for this specific area of industrial development by conducting training in industrial practice including quality assurance, management and marketing.

Marketing

Marketing is an unsurmountable problem besetting the development of the plant-based industry in developing countries and marketability will be a crucial factor in determining the failure or success of these industries. The market outlets can be for local use and for export. As for local use, some products could reach the consumer directly while others have to be either further processed or used as secondary components in other industrial products. Hence user industries have to be promoted so that locally produced extracts can be used to save foreign exchange needed for importation of such additives.

Further processing to yield value added products will be limited by the local demand situation unless they could be produced at prices to be competitive in the world market. Even if the cost of production is low and quality of the products is good, substantial market promotion has to be undertaken in order to penetrate the world market.

Market tie-ups with progressive entrepreneurs from the developed world would be a convenient and a realistic option for securing markets for the finished products. Joint ventures or trade agreements could be initiated with companies that are expanding their production to meet the ever increasing demand for green products.

Research and development

Industrial development requires parallel research and development. Research in chemistry and bioactive components of indigenous flora of developing countries has been ongoing for quite some time, funded by multi-/ bi- lateral aid or non-governmental donor organisations. A systematic and a concerted approach to this activity has not been maintained for want of sophisticated equipment and high-cost chemicals. Much of the research has been mainly academic. The concept of applied research in the industrial use of plants has not received much attention.

Figure 3: Scheme for development of processing of NWFP

Research in support of industrial development encompasses all activities ranging from the development of superior propagation materials, agrotechnology, low cost and efficient processing technologies to improve quality and yield, new formulations to new products and the marketing of finished products.

Registration and property rights

Many developing countries do not have procedures to register medicinal plant preparations although they are widely used for the health care needs of the majority of people. The regulations if any, are very stringent requiring the same standards expected of modern medicines. WHO has recently published guidelines for the assessment of herbal medicines taking into account the long and extensive usage of them (WHO, 1991). These guidelines should encourage developing countries to relax some of the current regulations to be realistic in recognizing the role of traditional medicines in the health care delivery of their countries.

The vital question of property rights to developing countries for the use of know-how and genetic resources in the development of modern drugs in developed countries has been discussed in many forums but without a final solution.

Technical information

As the use of plant-based drugs has declined with the introduction of synthetic drugs especially in developing countries, the need to collate all available knowledge on medicinal plants and their uses has become imperative particularly because of the recent revival of interest in the use of "natural" medicines. In view of the greater demand for information on traditional uses and proper identification, and the enormous volume of information being generated, a user-friendly information storage and retrieval system will be of considerable importance. As such a computer database would be of invaluable assistance to developing countries in R & D work on industrial utilization of local plant resources.

Data on the medicinal plants are also available in international journals and a number of databases, the premier being Napralert established at the University of Illinois in Chicago with WHO assistance. Many developing countries lack the resources to subscribe to research journals or acquire access to these databases. In fact, the data required by the scientific personnel in developing countries with respect to technologies and methods used for processing and formulation of medicinal plants are not readily available in the literature nor in the databases as some of these are patent-protected.

Conclusions

A scheme for the establishment of processing industries based on plants is given in Figure. 3. It must be emphasised that the proper coordination of the multidisciplinary activities needed for processing is vital for the success of industries venturing into this field.

The development of any industrial processing activity has to be linked to the specific needs, socio-cultural background, resource potential and the technological capabilities of each country. Consequently, any integrated development approach adopted has to exploit the full potential of this natural resource by providing a proper scientific, technological, economic and an industrial base. Above all, developing countries' research and development capabilities, including human resources, have to be greatly enhanced so as to ensure the growth of industries based on medicinal and aromatic plants.

Sustainable development of industries based on plants requires multi-disciplinary activities and close collaboration between scientists, government officials, NGOs and international organizations. Such efforts have not received much attention resulting in the slow development of the economic uses of renewable resources. Hence it is important that more action-oriented plans are initiated to exploit the full potential of these resources, bearing in mind the conservation issues such that rural household incomes and national economies could be augmented.

References

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http://www.fao.org/docrep/w7261e/W7261e07.HTM