Vernonia galamensis: A new crop for Ethiopia, tropics

By Tesfaye Baye (Ph.D.) | August 24, 2006

Vernolic acid is useful raw material for manufacturing paints and coatings and has great value in the oleochemical industry. Currently, no oilseed crop has been commercialized as a source of natural epoxidized oils and demand for epoxidized fatty acids is met by the chemical epoxygenation (epoxidation process) of the carbon double bonds present in highly unsaturated vegetable oils, such as soybean and linseed oils, or by synthesis from petrochemicals. Epoxy fatty acids are widely used in oleochemical industry as plasticizers and stabilizers of Polyvinyl chloride (PVC), in reformulation of oil based paints, in cosmetics, and pharmaceutical applications. In this type of application Vernonia oil has a built-in advantage in that it is already epoxidized and found in abundance in the seed oil, thus could be used as a substitute for currently used synthetic epoxic acids such as from soybean and linseed.

The naturally occurring epoxidized oil (vernolic acid) of Vernonia and the chemically epoxidized soybean (Glycine max L.) and linseed (Linum ustitatissimum) oils are similar, but there is an important difference. Chemically epoxidized soybean and linseed oils are highly viscous and are non- pourable below 00C. Vernonia oil, however, has low viscosity and can be stored below 00C and, hence, has very good cold flow properties. The low viscosity will permit the oil to be used as a solvent alkyd- resin paint, which will become part of the dry paint surface and prevent the evaporation (emission) of volatile organic compounds that contribute to production of smog and pollute the air unlike conventional solvents such as peracetic acid or terpentine in current use.

In USA, about 325 million gallons of paints are manufactured annually which are the major pollutant. Ozone is especially serious in big cities like California’s Los Angeles Basin where emissions of volatile organic compound (VOC) from paints and varnishes are 22 tons per day. These, along with other sources, react with nitrogen oxides to produce ozone, a deleterious component of photochemical smog. Researchers estimated that at least 237 ml of Vernonia oil can be used in each of the 1,230,258,900 liters (325 million gallons) of oil-based paint produced in the U.S each year, thereby reducing emissions of annual VOCs by at least 72,575 tons. To meet this demand, it has been estimated that at 998kg/ha oil yield production approximately 147176 ha of Vernonia would be required just to meet the annual needs of the U.S. paint industry. This doesn’t include paint production in other countries nor the potential demand from other use of Vernonia oil such as for lubrication, adhesives, etc. It is also forecasted by the year 2059 little of the world’s petroleum oil well is likely remaining to serve the ever increasing demand of the world. The long term solution to the problem may be that of utilizing agriculture and forestry for the production of renewable industrial resources. It is then possible to stabilize the burden of a threatened petroleum shortage, an unfavorable import-export balance, and increasing health and safety regulations in the manufacture and use of chemicals.

The seed meal of Vernonia can be used in the animal feed industry and the various parts of the plant as a medicine to treat a variety of diseases. In addition, the Vernonia plant tolerates substantial shade, which makes it ideal for agroforestry. The species naturally grow under low-rainfall (as little as 200 mm) and marginal conditions and is most suitable for dryland farming. These features make the plant a prime candidate for arid and semi-arid regions, where it grows without competing for land with food crops, create diversification of cropping systems and products and, hence, filling an ecological niche, serves as a break crop to prevent pest damage, as an insurance against crop failure and as a new cash crop. In addition to that, developing countries can capitalize on growing a new industrial crop for export and for their own industrial development. The plant could be also of interest to farmers in developed countries wishing to diversify and find an alternative and environment friendly crop. The oleochemical industry has also great interest in the utilization of new vegetable oilseed crops including Vernonia galamensis which have specific fatty acids with unique chemical structures and special properties as ingredients in the production of a range of specialty products.

However, being recognized as a potential oilseed plant only recently, not much information is available and even the limited available information is largely scattered, restricted in scope. I believe that the plant has great potential in the 21st Century; however, it needs collaboration among individuals/ industry and organizations to exchange research results for the near future commercialization of the species. In this regards the effort made by Vernique, to produce and commercialize the plant in its birth place, is indeed encouraging!

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For further information contact:
Tesfaye Baye, PhD
Email: btesfaye@yahoo.com

Reference (interested can get a copy)
Tesfaye Baye. 2004. Exploration, Genetic Diversity and Seed Quality Analyses in
Ethiopian Populations of Vernonia galamensis. Cuvillier Verla. ISBN: 3-89873-970-8.