Washington DC, November 19: London schoolchildren recently discovered that some of their families' soup recipes, which have been passed through generations, have antimalarial properties. Researchers helped the schoolchildren test their family soup broths for activity against the malaria parasite, for a study which was published in the Journal Archives of Disease in Childhood.

Several of the soup broths, collected from traditional family recipes that originated around the world, showed activity against the malaria parasite Plasmodium falciparum, either by curbing its growth or preventing it from maturing. Home Remedy of the Week: How to Treat Cold and Flu with Chicken Soup (Recipe Inside).

The soup recipes had been passed down through the generations for the treatment of fever. Five of the broths were able to curb the growth of the parasite in its disease-causing stage by more than 50 per cent. In two of these, the inhibitory activity was comparable with that of a leading antimalarial drug, dihydroartemisinin.

Four other broths were more than 50 per cent effective at blocking the ability of the parasites to mature to a form that infects mosquitoes, potentially blocking the process of transmission.

Dihydroartemisinin contains artemisinin, which was isolated from a traditional Chinese herbal medicine. The researchers behind the new study hope that they may similarly discover new antimalarial compounds from the work looking at the soup. The next step is to identify the active ingredients responsibly.

Lead researcher Professor Jake Baum, from the Department of Life Sciences at Imperial, said: "Malaria kills more than 400,000 people per year and infects more than 200 million, yet resistance to our frontline drugs continues to emerge. We may have to look beyond the chemistry shelf for new drugs, and natural remedies shouldn't be off our watch list, as artemisinin shows."

The pupils brought in samples of homemade clear soup broths from family recipes from across Europe, North Africa, and the Middle East. Filtered extracts of the broths were then tested against two stages of the parasite: when it can infect mosquitoes, and when it can cause the disease in humans.

The recipes for each of the broths varied. They were vegetarian, chicken or beef-based, with no particular ingredient common to those with the strongest antimalarial activity. The active ingredients in the broths studied are yet to be identified and tested. To move forward, the active ingredients would need to be isolated, before tests of toxicology and effectiveness, first in human cells and later preclinical trials.

Professor Baum said: "It's really interesting to find potential routes for future drug development in something like your grandmother's soup. In all honesty, the true strength of the study, however, was engaging children in the idea of what's the difference between a natural remedy and a real medicine - the answer is evidence! The children understood that soups could really become a drug if you test them the right way."