A natural substance obtained from the seeds of a "miracle tree" could be the answer to inexpensive water purification in the developing world, US scientists say.
Research on the potential of a sustainable water-treatment process requiring only tree seeds and sand has been published in the journal Langmuir.
According to Stephanie B. Velegol and her colleagues, removing disease-causing microbes and sediment from drinking water requires technology not always available in rural areas of developing countries.
For an alternative approach, Velegol looked to Moringa oleifera, or the "miracle tree," a plant grown in equatorial regions for food, traditional medicine and biofuel.
While prior research showed a protein in Moringa seeds can clean water, that approach was too expensive and complicated, so Velegol's team looked to develop another way to tap into the seeds' power.
They added an extract of the seed containing the positively charged Moringa protein (which binds to sediment and kills microbes) to negatively charged sand.
The resulting "functionalised," or "f-sand" proved effective in killing harmful E. coli bacteria and removing sediment from water samples.
"The results open the possibility that ... f-sand can provide a simple, locally sustainable process for producing storable drinking water," the researchers said.