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Medicinal plants
Besides a healthy diet from NTFPs, many local people directly depend on medicinal plants and knowledge
to use them appropriately. Often specialised people, older women, in the village have a wealth of knowledge
of numerous forest plants used in medicinal formulas, which they acquired over generations. Medicinal
plants often also have overlapping uses with traditional forest foods. All parts of medicinal plants maybe
used: roots, flowers, bark, lianas, leaves, nuts or resins. Some are used or sold fresh, others dried and
mixed with other medicinal plant or animal parts. Some plants are processed by the domestic
pharmaceutical industry for the domestic market, but at village level local healers depend on fresh materials.
The most common methods for preparing a medicine of a species is boiling the plant part in water and
drinking the tea extract after removing the cooked parts (decoction). It is also common to boil several parts
of medicinal plants together (concoction). Plant parts may be soaked in hot or cold water (infusion), or in
alcohol (tonic).
A limited number of medicinal plants are collected or cultivated for the export, like. Cardamom (Amomum
sp.) and malva nuts (Scaphium macropodum) both used in Chinese medicine, are the most important export
products, together representing 60-70% of the total NTFP export value for Lao PDR.
Many medicines, both traditional and ‘western’, are based on wild plants or compounds extracted from them.
Medicinal plants are important in almost all the countries in the region. More than 50% of the population in
the developing countries of the region is believed to be dependent on medicinal plants for curing various
illnesses. After a decline in medicinal plants and their derivatives owing to the growing volume of competitive
synthetic products currently marketed, there has been a recent upsurge in traditional medicine. The
expanding market for homeopathic and phyto-therapeutical products in the industrialized countries provides
new outlets for a number of botanical products. Examples of some plants are Dioscorea sp., Cinnamomum
spp. and Styrax benzoin. However, only a small number of plants exist from which individual constituents
are isolated and used as medicines, either alone or in combination. Nitrogen compounds extracts occur in
the form of protein and free amino acids and alkaloids, which have a strong biological activity (toxicity,
anesthesic effect, stimulation of the nervous system). Other extracts like exudates from Dragon’s blood or
Daemonorops are used as an astringent, or camphor from Cinnamomum. They are often abundant in roots,
bark, leaves, seed or certain plants (strychnine, berberine, quinine). In addition to medicinal plants which are
sources of alkaloids, there are some which are highly valued as tonics, such as Ginseng.
About 4,000 to 6,000 botanicals are of commercial importance. However, trade statistics for individual
medicinal plants are difficult to estimate, because they are not itemised in national trade data, and some of
the essential oils, such as cinnamon leaf oil are also used in medicine. Trade is further complicated because
of various levels of secrecy maintained by the traders and because of the complexity of the trade structure
itself. In 1992, total world trade in medicinal plants was about US$ 171.234 million, of which 20.9%
originated from countries in Asia and the Pacific, namely, India (11.2%, including 2,000 species), China
(3.8%, including 5,000 species) and Thailand (1.3%, incl. 200 species). The EEC (Germany and UK), Japan
and the USA are the main importers, with Hamburg (Germany) the leading trading center for medicinal
plants. In 1996 the global international trade in medicinal and aromatic plants exceeded 440,000 tonnes
valued at US$1.4 billion.
Only little specific documentation exists about the useful properties of medicinal plants. This is also because
people and pharmaceutical companies are reluctant to share their knowledge on which their incomes
depend on.
According to a 2003 National Decree regarding medicinal natural resources, medicinal plants are
categorized in 3 groups. Group I includes rare and endangered plants while Group II contains medicinal
plants which have commercial values, and Group III includes plants which are abundant. For Group I
exploitation and harvesting has to be certified from the Ministry of Health and concerned authorities. For
Group II plants exploitation and harvesting has to be certified by providing a management plan covering
harvesting and reforestation. Some examples from group II are: Coscinium fenestratum, Amomum
ovoideum and Cinnamomum cassia.