Dr. M. S. Eltohami
Sudan is the largest country in Africa with an area of 2 496 138 km2. It lies between latitudes 3║ N and 23║ N and longitudes 21║ E and 39║ E. It has common boundaries with nine countries: Egypt, Libya, Chad, Central Africa, Zaire, Uganda, Kenya, Ethiopia and Eritrea.
The climate of Sudan ranges from completely arid to tropical zones with a wide range of bioclimatic regions, from the almost barren deserts in the North to the tropical rain forests in the extreme South of the country. The diversity of the climate of Sudan is responsible for its very rich flora. Research on medicinal and aromatic plants began a long time ago, but this was carried out in a scattered and unstructured fashion until the establishment of the Medicinal and Aromatic Plants Research Institute (MAPRI) in 1972.
The medicinal and aromatic plants found in Sudan are both wild (Table 1) and cultivated (Table 2).
USES OF WILD MEDICINAL AND AROMATIC PLANTS
The dried exudation from the stem and branches of Acacia senegal is used as a demulcent, suspending and emulsifying agent. It is also used in textiles, confectionery and pastes. It contains mainly magnesium, calcium and potassium salts of glycosidal acid (known as Arabic acid), and enzyme oxydase.
The dried mucilaginous substance obtained from leaves of Aloes sp., Aloe crassipes, found in northern and eastern Sudan, and A. sinkatana, found in the East, is used in small doses as a laxative.
The roots of Balanites aegyptiaca contain steroidal sapogenins, whereas the bulb contains sugars and saponins. The leaves and fruit contain disogenin, while the kernel has a high oil and valuable protein content. The maceration of the fruit and seeds is used as a laxative and anthelmintic. It is used in the food, animal feed and pharmaceutical industry as a precursor.
The essential oil of Ocimum basilicum obtained by distillation is used in perfumery, production of aroma and in the food industry as a flavouring agent. It contains volatile oil containing cineol, pinene, methyl chavicol, d-camphor and ocimene.
The resin of Citrullus colocynthis is used as a gastro-intestinal stimulant and as a powerful purgative, as well as a hydrogogue cathartic and anti-rheumatic cure in traditional medicine.
Cymbopogon proximus contains a bitter oleo resin, a toxic volatile oil and a saponin used extensively in indigenous medicine as a diuretic, colic painkiller and antipyretic in fever.
Datur stamonium, D. metel, and D. innoxia are sources of commercial hyoscyamine. They contain alkaloids, hyoscine, hyoscyamine, as well as atropine. The constituents of Hyoscyamus muticus (hyoscyamine, atropine and hyoscine) relieve pain caused by the excessive use purgatives. It is also used as a cerebral and spinal sedative.
The leaves of Eucalyptus globulus are used as astringents in the form of cigarettes in cases of asthma. The oil is used as an antispasmodic, deodorant and anti-irritant.
The resin, gum, and volatile oil of Boswellia papyrifera are used to make incense and as an ingredient in plasters and fuming pastilles.
Gum exudates of Acacia nilotica are used as an antidiarrhoetic. Pods of Acacia seyal contain more than 20 % proteins and are very nourishing for livestock.
Fruits of Tamarindus indica are used as a gentle laxative, refrigerant and against malaria. They contain free and combined organic acids (tartaric, malic, and citric), potassium tartarate and 25-40 % invert sugars.
USES OF CULTIVATED MEDICINAL AND AROMATIC PLANTS
The steam distilled fruit oil of Pimpinella anisum is an ingredient of carminative and expectorant medicines for children. The greatest quantities of Anise, however, are used to flavor liqueurs and in confectionery and perfumery. It contains 3 % essential oil (Aniseed oil) with 90% anethole.
Solenostemma arghel contains an acidic resin, glycoside, choline, phytosterols and amyrine. It is used in indigenous medicine as an effective remedy for coughs. The infusion of its leaves is used for gastro-intestinal cramps and infections of the urinary tract.
The ripe seeds of Black cumin (Nigella sativa) have camphor like scent and bitterness and an aromatic taste. They are used in cooking and as substitute for peper and can be sprinkled on bread and cakes.
The dried fruits of Ammi majus contains ammoidin, ammidin and magudin as well as oils and protein. They are used for treatment of leucoderma and skin diseases.
Capsicum fruits (Capsicum minimum) contain up to 0.14 % pungent principle capsicin, non -pungent alkaloid, fixed oil and vitamin C. The fresh fruit is used as stimulant and stomach disorders and is mainly applied externally in the form of extracts, tinctures, ointments and plasters to treat rheumatism and sciatica.
Ricinus communis is medicinally used as a strong purgative, for cosmetic preparations, lubricant and disinfectants. Castor beans, which contain about 50 % oil, are an extremely toxic albumin (ricin) and an alkaloid ricinine.
Caraway (Carum carvi) is stomachic, antispasmodic, carminative galactogogic, antispasmodic and anthelmintic. The fruit is widely used as a flavoring agent in food products such as bread, cheese, pickles and sauce. The main constituents include essential oil (3-5 %) with carvone, limonene and tannins.
Dried coriander (Coriandrum sativum) is used extensively for both bulk and flavor in sausages, corned beef and similar meat products. Some coriander seed is distilled and the solvent extracted gives an essential oil.
Oleoresin seeds contain up to 0.07 % of essential oil, the principal constituent of which is dextro linalol.
Seeds of cumin (Cuminum cyminum) are used as a condiment, an agreeable aromatic and in veterinary medicine.
Fennel oil (Foeniculm vulgare) is used in European countries in the flavoring of food and liqueurs and in the perfumery industry. Pharmaceutically it is used as an agreeable aromatic and carminative. The main constituents are essential oils (up to 6 %) with anethole and fenchone.
Fenugreek seeds (Trigonella foenum-graceum) include a fixed oil (about 70%), a mucilage and sapogenins (1-2 %). Seeds are generally found in most blends of curry powder and foodstuffs and animal feed.
Guar gum, extracted from the dried ripe seeds of Cyamposis tetragonoloba, contain 25% proteins and 1.6 % fat. It is used in sizing of paper and, mixed with starch, as a valuable textile size as well as a stabilizer in emulsions thickener in food, pharmaceutical and cosmetic products. Much attention had been drawn to guar as a possible oral hypoglycemic agent.
The sepals of Hibiscus sabdariffa contain flavonoids and red pigment comprising gossipten and hibiscin together with phytosterolin and organic acids malic ,citric, tartaric, ascorbic and hibiscic acids. These seeds also contain a high percentage of mucilage (62 %) and a fixed oil. The ripe calyces are used as hot and cold beverages. Medicinally it is used as antispasmodic, hypotensive, antimicrobial and for relaxation of the uterine muscle.
The fruits of Ammi visnaga have the effect of relaxing muscles and lowering tonicity of the ureter. A decoction is used to ease the passage of kidney calculi. It is also the source of khellin.
The dried leaves of Lawsonia inermis (Henna) contain Lawasone, tannin mucilage and fat. They are used as a dye for hair, skin and nails; medicinally it is used as a fungicide.
A volatile oil, distilled from the leaves of lemon grass (Cymbopogon citratus), is used in perfumery, cosmetics and soap.
Peanut oil is a refined oil obtained from the seeds of one or more of the cultivated varieties of Arachis hypogaea. It is an edible oil which resembles olive oil, hence its use as a vehicle for liniments and as a lubricant, and in particular as a solvent for injections. It saponifies slowly but yields excellent white soap.
The leaves of Cassia acutifolia contain sennosides, aloe-emodin and rhein. The water extract of the leaves and the fruit is taken as a laxative.
In the past, people depended exclusively on herbal remedies or traditional medicine. They also used some wild plants for cosmetics and perfumery by extracting the oils with primitive methods. In recent years, however, medicinal plants have represented a primary health source for the pharmaceutical industry. Large quantities are used for the preparation of infusions and decoctions both in the countries where traditional medicine is still of great therapeutic, social and economic importance, and in the production of important pharmaceutical products abroad.
The government is now giving greater attention to the cultivation of crops in demand on the world market. The increase in size and number of irrigated schemes has changed the composition of some flora, leading to the disappearance of some plants and decreasing the area and the availability of others. Some of these important herbs are not cultivated in commercial quantity but are gathered haphazardly. For example, the poor organization and collection of this plant has led to a decrease in its quality and as a consequence decrease in its value and price.
On the other hand, the Government has imported some improved hybrids and varieties which have adapted to the Sudanese environment e.g. hyoscine contains plants (Datura inermis, Hyocyamus niger). If these are cultivated on a large scale, they could represent an important source of hard currency, besides satisfying the market needs.
The analysis of price and cost indicated that the price of export in dollars is stable. The greater part of costs is for labour. Salaries increased rapidly in the face of the continuous increase in the price of consumption and the higher cost of the main social services. For some plants such as Umbilefferous, 60 % of the cost is for labor because its harvest depends mainly on hand labor. Occasionally labor costs may rise up to 80 % or more as in the case of Senna and Rosella in rainfed areas. Mechanized crops like sesame and roundnut have a relatively low cost due to a low requirement of labor.
Prices depend on the efficiency of production and the competition in the world market. More attention to the productivity of the land and labor efficiency is required. Decreasing production costs by introducing mechanized systems in the agricultural work will lead to a negative impact in the social side by increasing unemployment. A solution to this problem is to develop the industrial sector especially where there is an abundance of the raw material. If the pharmaceutical industry is developed and all stages of production is undertaken within the country, this would open up opportunity for jobs and simultaneously lower the prices of drugs thus saving considerable hard currency which is presently paid for export of similar drugs. This, in turn, would lead to an increase in the standards of living of the population and improve welfare.
Table (1) : Wild medicinal and aromatic plants of the Sudan.
|Scientific name||Local name (s)|
|Acacia nilotica (Linn.) Willd.exDel||Sunt, Garad (fruit)|
|Subsp. nilotica Brenan|
|Subsp. tomentosa (Benth.)|
|Acacia senegal (Linn.) Willd var senegal||Hashab|
|Acacia seyal Del.||Talh|
|Var. seyal Brenan|
|Var. fistula (Schweinf.) Olive.|
|Agremone mexicana L||Agresone|
|Ambrosia maritima L.||Damsisa|
|Balanites aegyptiaca Del.||Heglig, Laloub|
|Boswellia papyrifera (Del.) Hochst.||Targ Targ, Gafal, Luban|
|Citrillus colocynthis (L.) Schard||Handal|
|Cymbopogon proximus (Hochst.) Staph.||Mahareb|
|Datura innoxia Mill||Alsakran|
|Datura metel Mill|
|Hapolophyllum tuberculata (Forssk.) A.Juss||Haza|
|Rauvolfia vomitoria Afz||Rawolfia|
|Solanum nigrum L.||Enab el Deib , Elmugad el aswad|
|Tamarindus indica L.||Aradib|
Table (2) : Cultivated medicinal and aromatic of the Sudan
|Scientific name||Local name (s)|
|Azadirchta indica A. Juss||Neem|
|Brassica nigra (L) Koch.||Khardal aswad|
|Carcica papaya L||Babai|
|Datura stramonium L.||Sakran|
|Foeniculum vulgare Mill||Shamur|
|Grewia tenax ( Forssk.) Fiori||Godeim|
|Hibiscus sabdariffa L.||Karkadeh|
|Hyoscyamus muticus L||Sakran musri|
|Nicotiana rustica L.||Tuback, Gamsha|
|Nigella sativa L.||Kamoon Aswad|
|Ocimum basilicum L.||Reehan|
|Ricinus communis L.||Khirwi|
|Senna alexandria Miller||Senna Maka|
|Solenostemma arghel (Del) Hayne||Hargel|
Prof. Dr. M. Koyuncu
MEDICINAL PLANTS AND THEIR IMPORTANCE
The term "medicinal plants" is used to determine the plants or plant products used by human beings in the protection against, or treatment of, illnesses. This clarifies that not every plant is a medicinal plant. Further research is needed to identify other plants with useful medicinal properties.
The term "herbal drug" determines the part/parts of a plant used for preparing medicines (for example: leaves, flowers, seeds, roots, barks, stems etc.).
According to the World Health Organization (WHO), 80% of the world population uses medicinal plants in the treatment of diseases and in African countries, this rate is much higher.
Medicinal plants contain biologically active chemical substances such as coumarins, volatile oils, alkaloids etc. In addition to these substances, plants contain other chemical compounds. These can act as agents to prevent undesirable side effects of the main active substances orto assist in the assimilation of the main substances. Opium juice, for example, contains other chemical compounds in additon tomorphine, and reports show that it gives fewer side effects than morphine administered on its own. The saponins found in the leaft extracts of Digitalis purpurea also assist the cardio-active heterosites to penetrate the blood more easily.
Folk medicines incuding herbal medicines and teas, in which the active compounds of the plants are directly used, are the most commonly used of medicinal plants. The use of pure active compounds, obtained from medicinal plants, is also widely used. 400 compounds, derived from plants, are currently used in the preparation of drugs such as vincristin and vinblastin. These compounds are used in the cure of cancer and can only be obtained from the plant Catharanthus roseus (Rose periwinkle). They cannnot be produced synthetically, and their market price per year is 100 million dollars.
The indiscriminate collection, and lack of replacement of these plants, is cause for serious concern since many of them risk extinction. A plan to replace such species is urgently required, since these medicinal plants are essential for treatment of many important diseases where other cures have yet to be found.
THE SITUATION OF MEDICINAL AND AROMATIC PLANTS IN TURKEY
More than 9.000 flowering plants grow in Turkey of which 30% are endemic. These plants are used mainly as food, medicines, spices, dyes, in fiber and herbal tea preparation, in the perfume industry, as well as for ornaments. The use of these plants forms part of the culture and tradition of the region in which they grow They are most commonly found in the old cities and towns of Istanbul, Kayseri, Gaziantep, Diyarbakr, Malatya, Sivas, Erzurum. These traditions are far less radicated in the newer settlements.
In recent years,drugs derived from plants have been the cause of great interest. Several papers have been published on this subject although not all have a reliable scientific background. Others, prepared by the the Faculty of Pharmacies are, however, scientifically reliable (Baytop, 1984)
The Turkish Faculty of Pharmacies is presently undertaking further studies in medicinal and aromatic plants and, in the past two years, a masters program on Phytotherapy has been set up.
The over 500 medicinal and aromatic plants found in Turkey include Allium (Onion), Origanum (Oregan), Mentha (mint) and Thymus (Thyme) which are used for flavouring. Salvia (Sage) and Sideritis species are used in hot drinks. Other species are used in food, as dyes and for ornamentation. Some of these plants contain poisonous compounds.
The importance of herbs is receiving increasing attention. Many developed countries are collecting new plants from gene centers all over the world, in order to conserve biological diversity and also to add new types of plants to their indigenous flora. Turkey now has a flourishing trade in medicinal, culinary and aromatic plants. These plants originate from the regions of Izmir, Istanbul, Antalya and Giresun. Exact figures for plants collected and exported are not available but an estimated 250 species are probably in commercial use. Some of them are gathered as a whole while only the useful parts (stems, leaves, roots, bulbs, rhizomes etc.) are collected in other cases. In the recent years some of them have been sold widely as ornaments after being dried and colored.
The outlook for improvement in production of native plants is good but to improve the profit margin, more plants should be processed within the country and not exported in their raw state. The desired quality and quantity can only be obtained by improved cultivation of these plants. At present income from export of medicinal and aromatic plants is greater than that from main forest products. In 1993 Turkey earned more than 80 million dollars from forest by-products (medicinal and aromatic plants, geophyts etc.) as compared to 50 million dollars from main forest products.
The protection of these plants is of vital importance. Present rates of collection are leading to the possible extinction of various species such as Gentiana lutea (Yellow Gentian), which is an important medicinal plant, in West and Northwest mountains of Anatolia; Galanthus (Snowdrop) and Cyclamen species and Orchids that produce salep. Origanum (Oregano), Salvia (Sage), Sideritis, Glycyrrhiza (Licorice) and Laurus (Laurel) are also over exploited. Further legislation is required to control excessive collection and export of these plants.