Scientists have discovered a number of substances in the Olon tree in South Africa capable of killing mosquitoes that transmit malaria. Even the bark of the tree holds a substance that can kill off the malaria-causing parasite.
In a study carried out by researchers at the University of Oslo, emphasis was placed on the effects of two African trees on mosquitoes that transmit malaria, as published in Science Daily. According to the results, substances from these trees can get rid of the mosquitoes carrying malaria, and the malaria parasite itself.
The two African trees that kill mosquitoes carrying malaria include the Olon tree that is found in areas between Cameroon and Congo, and a related tree situated in Mali. The researchers found the most active compounds in the Olon tree, although the bark from the Mali tree proved to have active substances as well.
“[Master student Nastaran] Moussavi applied substances from the bark of the Olon tree to the neck of the mosquitoes, in order to investigate if the substances had toxic effects," Associate Professor and project leader Helle Wangensteen explained. "This caused the mosquitos to die, literally as flies! The experiments showed that pellitorine is toxic to mosquitoes.”
The chemical substances known as pellitorine and dihydronitidine have been previously discovered in other plants. For instance, Professor emerita Berit Smestad Paulsen who works at the School of Pharmacy is aware of the effects of the African tree's bark on malaria patients, and has been working with Mali healers for the past years.
However, findings on the African trees' effects on malaria-carrying mosquitoes and their parasites were limited prior to the Norwegian researchers’ work. Although findings on the trees’ and their effects on malaria have been published more than a few times, there has been no response from the pharmaceutical industry. According to professor emeritus Karl Egil Malterud, there could be a number of reasons why they have not been contacted. For instance, the global pharmaceutical industry may not always take interest in “Third World” problems.
“These findings have been published in scientific journals, which makes it more difficult to obtain patent protection for active substances," Malterud further suggested.
As pointed out by the New England Journal of Medicine, death toll among children, particularly in Africa, remains high. Malaria remains to be one of the most dangerous infectious diseases in the world, affecting over 200 million people annually.
