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Freely-Speaking: A Bio-based Technique for Removing Bacteria

Example of how ciliates look
(Source: http://www.woodrow.org)
This week, DW Radio covered an interesting topic in their science news radio show.

In light of the recent EHEC outbreak in Germany, experts have been trying to trace the source of this deadly outbreak. For those who do not know what EHEC is, it stands for Enterohaemorrhagic Escherichia coli. In other words, these special strains of E. coli are very tough bugs that can cause intestinal bleeding - obviously not desirable and potentially dangerous.

The search for possible sources has lead back to water treatment plants because the majority of water treatment plants treat water according to ecological aspects only, that is to say, they ensure that nutrients and waste in the water do not exceed certain levels. Many German water-treatment plants do not specifically try to reduce the number of bacteria in the water. That part is left to water companies that produce drinking water. The result is that high concentrations of bacteria from water treatment plants could theoretically make it back into the human intestines again if exposed to them (swimming in water streams, ingestion of fruits that were exposed to this water etc.). It is of course possible to try to remove bacteria from the water through several means (UV, chlorine, filtration), but these techniques tend to be rather expensive.

Within this framework, Forschung-Aktuell covered the research of Dr. Wolfgang Eichler, who proposed another approach: using ciliates, (single-celled eukaryotic cells that eat bacteria) to reduce the bacterial count of water coming out of water treatment plants. In initial tests under controlled conditions, his research group has found that a selected strain of ciliates was capable of reducing the count of E. coli bacteria by 25% per hour.

You can read the abstract of this research presented just recently here.



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