Invasive weed Prosopis juliflora candidate for malaria drug development

By Gatonye Gathura

Scientists are developing a possible malaria treatment from the invasive weed, Prosopis juliflora, known as Mathenge in parts of Kenya.

Scientists from Kenya and United States Army Medical Research Directorate- Africa, report extracts from the plant to have shown strong anti-malarial activity.

The findings were reported in a poster presentation at the annual conference of the Kenya Medical Research Institute (Kemri) held in Nairobi last month.

In 2006 the weed was taken to the High Court of Kenya by residents of Baringo County for invading and colonizing their land, knocking off the teeth of their goats and killing livestock and wildlife.

The court had then held the State liable for the loss visited on the peasants by the plant and ordered it to effect remedial measures.

Since then, the Government has supported many  activities including turning the weed into charcoal, electricity, animal feed ‘chapatis’  and even furniture.

However last year in an extensive study the Kenya Forestry Research Institute (KEFRI) said the efforts so far had failed to stop the spread and negative activities of the plant.

“Although the management of prosopis by utilization has been promoted in Baringo for 10–15 years, its spread has not stopped or slowed it down,” said KEFRI.

The malaria drug-making initiative has nothing to do with the plant’s environmental misadventures, but if successful it could dramatically change its fortunes and those of the host communities in ways only comparable to the effects of the current first-line malaria treatment.

The current first-line malaria treatment is derived from a small herb from Asia called sweet wormwood or Artemisia annua. For this development a Chinese chemist, Youyou Tu won the 2015 Nobel Prize in medicine.

The new initiative in Kenya also involves Kemri-Kisumu, Jomo Kenyatta University of Agriculture Technology, the International Centre of Insect Physiology and Ecology and Egerton University.

“The identified antimalarial agents in the plant can be tapped into a generation of not only curative but also malaria transmission-blocking agents,” the scientists say in the poster.

They report this as the first detailed study of the plant’s activity against the malaria-causing parasite.

The active compound in the plant, indolizidinium, was found to act moderately fast against malaria arresting its effects within 24 to 72 hours.

The extract was tested against the conventional malaria treatment primaquine and reported to compare well.

The research also involves a second plant called Cissampelos pareira which was also reported to be a promising malaria drug candidate.

This is also an interesting turn for Mathenge which in 2017 was accused of abetting the spread of malaria.

A study by among others the Nairobi based Centre for Agriculture and Biosciences International (CABI) published in the Malaria Journal said the plant encouraged the increase of malaria-transmitting mosquitoes.

The study said the plants’ abundant flowers provide critical sugars for the survival of mosquitoes hence encouraging the growth and survival of huge populations.

Scientists have estimated that with or without the current control measures, Mathenge could take up over 80 per cent of arid lands replacing about 19 million people, 70 per cent of livestock and 90 per cent of Kenya’s wildlife.

About Gatonye Gathura 41 Articles
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