Virtuous spirulina

Spirulina, the nutrient-rich blue-green algae also known as Arthrospira, has been harvested by indigenous peoples in Mexico and parts of Africa for hundreds of years. In the past two decades, commercial production has begun in many countries including Mexico, Thailand, Chile, India, Myanmar, Taiwan and the United States. Current worldwide production is estimated at about 3,000 tonnes. However, in Africa the potential of this spiral-shaped algae to boost health, immunity and incomes has so far been realised only in Chad, where the annual spirulina harvest of about 40 tonnes is worth US$100,000.

credit: Olivier Barbaroux

Spirulina blooms naturally in Lake Chad (or Kossorom) and the other saline-soda lakes of the region. Women of the Kanembu tribe, the largest in Chad, adhere to rigid customs when harvesting, cleaning and drying the algae in the sun, and the dried product, called dihé, is used as a soup base served daily with corn, millet or sorghum meal. Surplus production is stored and sold every few weeks at the local market. Wholesalers take the dried algae cakes to larger markets, and even across the border to neighbouring countries, such as Nigeria and Cameroon.

Incomes...

Researchers reported in 2000 in the Journal of Applied Phycology that the money women earn from selling dihé is used for personal needs, which permits them a certain degree of financial independence. Many buy goats as insurance against hard times and for their milk and butter, which they both consume and sell. And, in female headed-households, dihé may represent the only means of subsistence.

Spirulina is often referred to as a superfood because it is 60-70 per cent protein and it also provides essential fatty acids, phytochemicals such as beta-carotene (which the body converts into vitamin A) and micronutrients, including vitamin B12 (which is rare in plants) and iron. In a 2002 review of almost 100 published studies of spirulina, most conducted in the last 10 years, Dr. Amha Belay stated in the Journal of the American Nutraceutical Association that the "evidence for its potential therapeutic application is overwhelming in the areas of immunomodulation, anti-cancer, anti-viral and cholesterol-reduction effects."

...immunisation...

A paper published in 2004 in the journal Medical Hypotheses states that regular consumption of algae may prevent or suppress HIV infection. The authors observe that Japan, Korea and Chad have in common a daily diet that includes algae or seaweed and anomalously low rates of HIV/AIDS that cannot be explained by differences with their neighbours in terms of intravenous drug use and sexual behaviour. Average daily consumption of algae in these countries ranges from between 3-13 g.

Belay - originally from Ethiopia and now scientific director of Earthrise Nutritionals, a spirulina research and production company in California - sees the crop as having huge potential for improving public health and incomes in developing countries. "The technology for mass cultivation and harvest of spirulina is well established," he says, adding that growing the crop in natural lakes is possible only if the water is sufficiently alkaline. Artificial ponds allow cultivation under controlled conditions but require adequate water supplies and higher startup costs. He stresses that production methods must be appropriate for local conditions.

...and innovation

One source of information on production methods is Antenna Technologies, a non-profit Swiss association of scientists, international consultants and researchers who develop and promote appropriate technologies for such basics as food, health and housing. Antenna offers free teaching modules on spirulina production, harvesting and drying techniques as well as background information. The association notes that spirulina can be grown year-round in warm climates and requires little more than water, commonly available fertilisers, and sodium bicarbonate (or, alternatively, wood ash) to make the water alkaline.

Article by Treena Hein