Researchers at Leicester University, UK, have developed a method to produce clean water using chemicals. This method would be helpful in areas where polluted river water poses serious health risks. Chemicals such as aluminium sulphate will effectively coagulate minute pollutants like sewage, allowing easy cleaning of water. But these chemicals are expensive. The team has used as an alternative, crushed seed powder from Moninga oleifera, a tropical tree. When mixed with water, the powder produces positively charged proteins in the solution which then interact with the negative charges in the suspended organic and inorganic matter, viruses which are easily removed through settlement and filtration.