MORINGA (Moringa oleifera): A Multipurpose Tree
River water when collected for domestic use can be full of impurities, particularly in the rainy season. Water carries sediment, solid objects, bacteria and other microorganisms (some of which can transmit disease). It is very important to remove as much of these impurities as possible to use the water. Large water treatment centers do this by adding chemical coagulants to the water. This causes the particles to stick together (coagulate) and sink. The clean water can then be withdrawn. The right chemicals, however, may not be readily available or may be too expensive. The alternative is to use a natural coagulant, usually made from plants. In certain parts of the world, this has been done on a small scale for centuries.
The Environmental Engineering Group at the University of Leicester, UK, has been studying the potential use of natural coagulants on a large scale in water treatment. Their work includes testing the natural clotting properties of crushed tree seed. Moringa oleifera . This tree is native to northern India and is now cultivated widely throughout the tropics. It is sometimes known as a “drumstick” because of the shape of its pod and “spicy horseradish” describing the taste of its roots. Moringa grows quickly from seed or grafts, even in poor soils. It does not need much care and can survive long periods of drought.It grows quickly – up to 4 meters tall, flowers and fruits were produced within a year of planting, during trials near Nsanje in southern Malawi. In some areas of southern India, two seed pod harvests are possible in one year.
USES OF MORINGA:
VEGETABLE
-Green pods, leaves, flowers and seeds that can be roasted
OIL
-The seeds contain 40% oil by weight.
-Used for cooking, soap making, as a base for cosmetics and in lamps.
WATER COAGULANT
-Traditionally used for “home treatment” in Sudan and Indonesia.
-Successfully used in large-scale water treatment in Malawi.
OTHER USES
-All parts of the plant can be used in a variety of traditional remedies.
-Powdered seed is used in ointment to treat skin infections caused by common bacteria
-Leaves and seeds can be used as feed for livestock or as fertilizer for the soil
-Can serve the fences or to break the force of the wind.
-Wood is a source of fuel. The main branches can be pruned to allow other branches to grow.
-Agro-forestry; to intercrop with other crops - moringa is good for adding nitrogen to the soil because of the pods and leaves it produces.
Water treatment for domestic use
Seed pods should be left to mature on the tree and collected when dry. The light “wings” and husks of the seeds are easily removed, leaving only the white part of the seed. This must then be ground very well and pounded using a pestle. The amount of seed needed to treat river water depends on the amount of impurities in the water. The user quickly becomes familiar with the amount of seeds to use for each type of water, as the amount of sediment changes with each season.
To treat 20 liters of water (amount equivalent to a large bucket) you need about 2 grams of crushed seeds (two level teaspoons of 5 ml or two full soda caps).
Add a small amount of clean water to the crushed seeds to form a paste. Place the paste inside an empty bottle – a soda bottle is ideal. Add 1 cup (200 ml) of clean water and shake for 5 minutes. This action activates the chemicals in the crushed seeds.
Filter the solution with a white cotton cloth by placing it in a 20 liter bucket of river water. The contents should then be mixed rapidly for two minutes and then mixed slowly for 10-15 minutes. During this period of slowly mixing the contents, the moringa seed particles will collect, coagulate with the bacteria and form larger particles, which settle to the bottom of the bucket and remain there. After one hour, the clean water can be withdrawn.
This process will remove 90-99% of the bacteria that cling to the solid particles, purifying the water. However, some harmful microorganisms that still remain in the water may not be removed, especially if the water is heavily polluted. To make the water drinkable, further purification is recommended – either by boiling the water or using a simple sand filter. Dried seeds (remove colorless ones) and powder can be stored. However, the paste must be prepared the day it is going to be used.
Large scale water treatment
Our experimental work was carried out in Thyolo in southern Malawi, where a water treatment site was built as a model system for village water treatment. Electricity is not required for operation. In Malawi in 1993, chemicals imported from South Africa cost the water company over £400,000 in valuable foreign currency. Our tests using moringa seed gave water purification results that were as good as the results obtained with commercial chemicals – at a fraction of the cost, 50-150 mg of whole seeds are needed for a liter of water. Simple tests on a jar will determine how many seeds will be needed.
Many developing countries could save a lot of money by adopting these ideas.
Vegetable products and oil
The moringa pod is an important commercial crop across India. In the south, many varieties have been developed with different pod lengths and growing seasons. The pods are sold at local markets. Green, unripe pods are cut into sections and canned in brine for export to Europe and the United States.
Elsewhere in the world, moringa trees are prized by peasants for the quality of their pods and leaves. The leaves have a high protein content of 27% and are rich in vitamins A and C, calcium, iron and phosphorus. One advantage is that moringa leaves can be harvested during the dry season when no other vegetables are available for sale.
Moringa seeds contain 40% oil by weight. Laboratory tests in Leicester confirmed that what remains of the seeds after oil extraction still contains the active coagulants. These can be used to treat water in the same way as described above. What is left of the seeds can be dried and stored. It can be obtained at no cost as a by-product of oil extraction.
This is an important point. Moringa seeds can first be used for oil extraction without reducing the effectiveness of water treatment. Moringa oil is of high quality and potentially has a high market value. Oil is of equal value, both for cooking and as a main ingredient in soap production. The demand for oil in Malawi is much higher than the current production within the country. Soybean oil is therefore imported from South America.
The visit was made to a village in southern Malawi that had many moringa trees, laden with pods. The trees are highly valued for the products they produce, but the villagers had not harvested the pods as they could not afford the imported vegetable oil that is needed to cook them as they did not realize that the moringa itself could provide the oil.
Conclusions
The planting of moringa by smallholders should be encouraged. This will improve their health and performance. This valuable tree will provide plant products and raw materials for oil extraction. Simple technology can be found to start small-scale oil extraction businesses in rural areas. Tests are being carried out by the ITDG of Zimbabwe.
The great potential of this tree and its various products has not been recognized. In southern Nigeria, moringa is known as idagha manoye – which translates as 'growing up without logic'. It can be hoped that in the future common sense will prevail and that the real potential of this tree and its many products will be recognized.
Addendums
Winged seeds of Moringa oelifera, when crushed, provide oil and a paste that can be used for water treatment and as animal feed.
In the water treatment, it is allowed to settle for 30 minutes.
