SANCOOP: Bacteria can be used to clean contaminated water


Photo U.S. Environmental Protection Agency (public domain)

Scientists have found bacteria that can clean polluted water. Their goal is to replace chemical cleaning agents with effective, cheap and environmentally friendly products from bacteria.

In densely populated areas in South Africa, clean water is scarce. There is water in lakes, rivers and other waterways, but this often can be contaminated and needs to be purified before use. Ground water can be used, but the regeneration of such water is too slow compared to the demand. Some of the particles that pollute the water are very small and difficult to sediment. Therefore, inorganic chemical agents are often used to separate the pollutants from the water. Researchers at the University of Fort Hare and GenØk – Centre for Biosafety in Norway are collaborating on finding a good alternative to chemical treatment of the water.

Degradable and risk free
The process of cleansing water by sinking suspended pollutants to the bottom is called flocculation. Flocculants are binding agents that separate the pollutants from the water so that the impurities can be removed. This method is widely used in the treatment of sewage-contaminated water and wastewater from industry and housing. However, such inorganic chemical flocculants are not biodegradable and are toxic. They can also adversely affect the environment. Therefore, researchers are working to find bacteria that can produce biological flocculants. They can be described as bio-flocculants. That is, they are biodegradable and non-toxic, thus, they are preferred to chemical flocculants in the treatment of contaminated water.

Too expensive and ineffective
– Available bioflocculants have so far been more expensive and less effective than the chemical options. We want to find cost effective bio-flocculants with high efficiency, explains Professor Anthony Okoh and Dr. Arinze Okoli, researchers at  the University of Fort Hare and GenØk respectively. Professor Okoh and Dr. Okoli explains that the Eastern Cape in South Africa has a unique diversity of species and is therefore a good starting point for searching for bacterial strains that can be tested. “We collect bacteria from the natural environment and study how to manipulate them so that they can efficiently produce good quality flocculants,” say the scientists.

How do the bacteria remove contamination?
During the project, researchers have found several good bioflocculant producers, including the bacterium with the name Bacillus sp. AEMREG7. “In addition to investigating the ability of bacteria to produce high quality bioflocculants, an important part of the project is to identify the genes and proteins involved, as well as to understand how they respond to different environmental conditions,” says Dr. Okoli. The scientists have for example found that the bioflocculant produced by the Bacillus bacterium has high thermostability, which means that it will have good effect under varying temperatures.

Chemical pollution from agriculture
In addition to pollution from sewage and industry, chemical pollution of water from agricultural fields is a challenge. The herbicide glyphosate and its degradation product AMPA, found in varying concentrations in the Eastern Cape environment, can affect both the amount and quality of the bioflocculants produced by the bacteria. The researchers are looking at the mechanisms and levels of glyphosate and AMPA that affect the ability of the bacterium to produce bioflocculants and study at the same time whether bioflocculants can be used to purify water contaminated with glyphosate and AMPA. The project is funded through SANCOOP, a collaboration between the Research Council of Norway and the National Research Foundation in South Africa.


Okaiyeto, K., Mabinya, L.V., Nwodo, U.U., Okoli, A. and Okoh, A.I. “Implications for public health demands alternatives to inorganic and synthetic flocculants: Bioflocculants as important candidates”, MicrobiologyOpen, 2016, 5(2), 177-221.Okaiyeto, K., Nwodo, U.U., Okoli, A., Mabinya, L.V. and Okoh, A.I. “Studies on a Bioflocculant Production by Bacillus sp. AEMREG7”, Polish Journal of Environmental Studies, 2016, 25(1), 236-245.

Okaiyeto, K., Nwodo, U.U., Mabinya, L.V., Okoli, A.S. and Okoh, A.I. “Characterization of a bioflocculant (MBF-UFH) produced by Bacillus sp. AEMREG7”, International Journal of Molecular Sciences, 2015, 16, 12986-13003

Okaiyeto, K., Nwodo, U.U., Okoli, A.S., Mabinya, L.V. and Okoh, A.I. “Culture conditions optimization and characterization of a bioflocculant produced by Bacillus sp. isolated from Algoa Bay, South Africa”, Journal of Microbial and Biochemical Technology, 2015, 5:4.

Okaiyeto, K., Nwodo, U.U., Okoli, A.S., Mabinya, L.V. and Okoh, A.I. “Evaluation of flocculating performance of a thermostable bioflocculant produced by marine Bacillus sp. ”, Environmental Technology, 2015, 37(14), 1829–1842.