 |
| Bark from Zanthoxylum species. Photo by Alex Popovkin |
In other articles, we have introduced scientific evidence that natural compounds that can treat or fight malaria infections. We have also introduced an Asian herb that has been used to treat malaria for centuries.
Now we provide clear evidence that the barks of two natural trees indigenous to Africa can be used to treat malaria. Furthermore, the bark extracts can also remove the mosquitoes that cause malaria.
What causes malaria?
Malaria is caused by Plasmodium parasites injected into the bloodstream with the bites of mosquitoes. Over thirty different species of Anopheles mosquitoes can transmit the parasite from one person to another.
Once the parasites are in the blood, they cause a range of symptoms. These include chills, fever, abdominal pain and inflammation. Symptoms can feel like influenza in the beginning of an infection.
There are multiple species of the parasites that can cause malaria. Each comes with a distinct incubation period. Plasmodium falciparum and P. knowlesi parasites will incubate for a week to two weeks before symptoms develop. P. vivax and P. ovale can show after three weeks and up to 10 months after infection. P. malariae parasites can take three to five weeks before showing symptoms.
Malaria infections can be fatal. Nearly a half million people die from malaria each year.
Two malaria fighting trees from Africa
Traditional healing has been increasingly ignored in Africa by conventional medicine. Too bad, because malaria was treated for centuries by some African traditional healers. They successfully treated patients with extracts from the bark of two trees. These are:
Olon tree (Zanthoxylum heitzii)
The Olon tree is a tropical tree that can grow over 100 feet tall. It has spiny leaves thick bark and a wide base. It grows in the tropical West Africa from Cameroon to Gabon south and Congo to the west. Olon lumber is used to build houses and the bark is used for medicinal purposes.
Senegal prickly-ash (Zanthoxylum zanthoxyloides)
The Senegal prickly-ash bush grows up to 45 feet. It has thorns and is used for its timber. It is also used as a spice and for medicinal purposes. It grows in the tropical region of West Africa, from Senegal to Nigeria.
Both trees belong to the citrus family, called Rutaceae.
The bark from both trees can be used to treat malaria and kill malaria mosquitoes. They also happen to grow where malaria rates are some of the worst in the world. Imagine that.
Five years of research proves malaria remedies
Researchers from the University of Oslo in Norway have studied the compounds of both of these bark extracts over the past few years.
Their research proves the bark extracts from the trees contain substances that not only kill the malaria parasite, but also kill the mosquitoes that transmit the disease.
A 2016 study tested the Olon bark extract against two of the malaria parasites:
• Plasmodium falciparum – human malaria parasite
• Plasmodium berghei – rodent malaria parasite
The researchers found the Olon bark extract inhibited the proliferation of the parasites.
The study found that three different compounds from the bark extract also inhibited the proliferation of the parasites. These three compounds are:
• Dihydronitidine
• Pellitorine
• Heitziquinone
The dihydronitidine compound was the most potent for killing the parasite in the blood. And the pellitorine compound was the most potent for killing the mosquitoes that transmit the parasite.
A subsequent study isolated other anti-parasitic alkaloids from the bark. These included:
• Isoarnottianamide
• Rhoifoline B
• Isobauerenol
• Hydroxypellitorine
• Sylvamide
These were found to support the bark’s anti-parasitic actions. But the greatest action came from the first three listed above.
University of Oslo Professor Karl Egil Malterud discussed how the research got started:
“This project started in 2011, when we were approached by the entomologist Bertin Mikolo from Marien Ngouabi University in the Republic of Congo’s capital Brazzaville. He had learned that local traditional healers were using extracts from the bark of a tropical tree to kill malaria mosquitoes and other insects, and he had demonstrated that the extracts could kill weevils and cockroaches. Now, he wanted Norwegian assistance to investigate whether the bark also contained substances that could kill malaria mosquitoes.”
Actually, the research found the bark extract had two different abilities – from different compounds in the Olon tree. Associate Professor Helle Wangensteen explained:
“We produced extracts from the bark of the Olon tree and found that it contained at least one compound that kills the mosquitoes that transmit the malarial parasite. But the bark also contains another substance that kills the parasite itself.”
The pellitorine compound is found in the bark of both trees.
The researchers then traveled to France’s Institute of Research for Development (IRD) to test the insecticide abilities of the bark extracts. Dr. Malterud described the results:
“This caused the mosquitoes to die, literally as flies! The experiments showed that pellitorine is toxic to mosquitoes.”
They also found other substances in the bark extracts were toxic to the mosquitoes. Dr. Wangensteen explained:
“We also found that a mixture of four main substances from the bark of the Olon tree had a higher toxicity than pellitorine alone, even if the other ingredients were not toxic separately. This suggests that there is a synergistic effect between the ingredients.”
Additional research from the University of Melbourne conducted additional tests to confirm the parasite-killing abilities of the two extracts. Indeed, they confirmed the results – the extracts proved to kill the parasite as well as kill the mosquito.
Pharmaceutical industry not interested
The World Health Organization has reported that 212 million people were infected with malaria in 2015. And some 429,000 people died of malaria.
Currently, most of the drugs supplied by the pharmaceutical industry have created resistance among the parasites. So many of the drugs are not working – and increasingly so. There is an absolute urgent need for new solutions.
Has the pharmaceutical industry contacted the University of Oslo researchers about these natural parasite-killing compounds? Nope.
There is an urgent need for new drugs – but the scientists have so far not been contacted.
Dr. Malterud is incredulous about the lack of response. He tries to explain it:
“I can imagine several reasons why we haven’t heard anything. One reason might be, to put it slightly maliciously, that the international pharmaceutical industry doesn’t always seem very interested in diseases that are mostly a problem in the “Third World.” The second possible reason is that these findings have been published in scientific journals, which makes it more difficult to obtain patent protection for active substances.”
The latter reason, as we’ve found among so many other natural compounds, is the most likely. Despite the fact that the pharmaceutical industry could package these natural-based compounds into an easily-distributed pill form, they aren’t interested. That’s because they cannot file a patent for a natural compound.
You see, it’s not about saving lives. It’s about market control. It’s about money.
Getting the word out
Dr.s Wangensteen and Malterud are now trying to communicate the information to those in regions that can benefit the most from these natural remedies. According to Dr. Malterud:
“In the short term, it is realistic to imagine that our colleagues in Congo may communicate the new knowledge to the traditional healers in the region. It could be useful for them to know that the bark from the Olon tree contains active compounds that have effects against both malaria-transmitting mosquitoes and the parasite itself. We can also contribute with new insights on how these substances can be used. For example, we discovered that water-based extracts contain relatively little of the active substances, whereas alcoholic extracts contain much higher concentrations. Perhaps it would be possible to spray the puddles where the mosquitoes hatch with a locally produced solution containing pellitorine.”
I hope this article helps spread that information. We’re talking public service here. Nearly half a million people are dying each year from malaria.
This research on the anti-malaria bark extracts is supported by the Functional Genomics Programme (FUGE) from the Research Council of Norway.
REFERENCES:
Goodman CD, Austarheim I, Mollard V, Mikolo B, Malterud KE, McFadden GI, Wangensteen H. Natural products from Zanthoxylum heitzii against malaria parasite. Malar J. 2016 Sep 20;15:481. doi: 10.1186/s12936-016-1533-x.
Moussavi N, Malterud KE, Mikolo B, Dawes D, Chandre F, Corbel V, Massamba D, Overgaard HJ, Wangensteen H. Identification of chemical constituents of Zanthoxylum heitzii against malaria mosquito Anopheles gambiae. Parasit Vectors. 2015 Oct 1;8:503. doi: 10.1186/s13071-015-1113-x.
Wangensteen H, Ho GT, Tadesse M, Miles CO, Moussavi N, Mikolo B, Malterud KE. A new benzophenanthridine alkaloid and other bioactive constituents from the stem bark of Zanthoxylum heitzii. Fitoterapia. 2016 Mar;109:196-200. doi: 10.1016/j.fitote.2016.01.012.
Overgaard HJ, Sirisopa P, Mikolo B, Malterud KE, Wangensteen H, Zou YF, Paulsen BS, Massamba D, Duchon S, Corbel V, Chandre F. Insecticidal activities of bark, leaf and seed extracts of Zanthoxylum heitzii against the African malaria vector Anopheles gambiae. Molecules. 2014 Dec 17;19(12):21276-90. doi: 10.3390/molecules191221276.
Røsjø B. African trees kill both malaria mosquitoes and the parasite. UiO. January 25, 2017
Gansané A, Sanon S, Ouattara LP, Traoré A, Hutter S, Ollivier E, Azas N, Traore AS, Guissou IP, Sirima SB, Nebié I. Antiplasmodial activity and toxicity of crude extracts from alternatives parts of plants widely used for the treatment of malaria in Burkina Faso: contribution for their preservation. Parasitol Res. 2010 Jan;106(2):335-40. doi: 10.1007/s00436-009-1663-y.