The seeds of the Moringa oleifera tree have been used to purify water and clean crockery since the days of ancient Egypt, but up until now scientists weren't sure exactly how they worked. Thanks to a new paper published in the journal Langmuir by researchers at Pennsylvania State University, part of the mystery has now been solved.

It had already been established that a protein inside the Egyptian seeds caused bacteria to clump together in the water and die, sinking to the bottom of the container to leave the water largely clear. But the latest discovery reveals how this is done: the academics found that the seeds actually fuse the membranes of said bacteria together. As those membranes are the main protection the bacteria have, disrupting them causes the cells to die.

That's not all though. The Penn State researchers have also worked out the best time to harvest the Moringa oleifera seeds: during the rainy season, when the seeds have reached full maturity. Previously, harvesting the seeds to capture them at the peak of their powers was largely guesswork, which meant it was difficult to assess to what extent the water they treated was purified.

These new breakthroughs are another step along the way to having this type of seed grown in areas where it is most needed, rather than just the areas where it occurs naturally. Because other parts of the seed are edible, it can be a useful food source for those in remote or impoverished areas, as well as a potentially vital way of cleaning drinking water.

According to the Water.org organisation, some 769 million people across the globe don't have access to safe and clean drinking water - this leads to around 840,000 deaths each year that could be prevented with improved water supplies. Most of these people (82 percent) live in rural areas, and it's here where the properties of the Moringa oleifera seed could make such a difference.

The scientists from Pennsylvania State University teamed up with botanist Bashir Abubakar, from Ahmadu Bello University in Zaria, Nigeria, as part of the research. Abubakar provided some of the seeds used in testing, and he says that their benefits go way beyond cleaning water. "[Local] farmers will have an additional income, because not only will they be growing Moringa for food, but they can also grow large plantations of Moringa for the seed," he said in a press release. "You can divert the money for other infrastructural and societal needs, either to improve the farmlands or to construct roads."

Further research is required before the seeds can be used to remove contaminations and leave water that's 100 percent clean and drinkable, but the end goal is now much closer, and could ultimately have a huge impact in developing nations. The researchers at Penn State are now seeking funding for additional studies.