Mahaica’s ‘mad scientists’ make mosquito repellent from Katahar flower


“Katahar” is an Indo-Guyanese Creole word that carries the idea of nothingness. If someone were to tell you you’re a Katahar, they are really dismissing you as worth nothing.

Darshanie Nanhu, 16, a student of the Bygeval Secondary School on the East Coast of Demerara, is no Katahar. And spare a thought for the fact that she also has no problems peeling off the thick green skin of the young Katahar, and then taking off the “flesh” from the seed, and then peeling the seed to get its contents for the curried dish; it’s a laborious task for most people.The vegetable named Katahar is, however, not to be dismissed. Curried Katahar, added to other curries with dhall and rice, is a must-have in good seven-curry, the dish mainly served at Hindu religious events.

When she was younger, Darshanie’s parents would light the dried flower of the Katahar plant (commonly called Bambalayke) and the scent coming from it would keep mosquitoes out. Good thing she remembered that, as it earned her excellent scores for her school’s exam project, and she is now the country’s latest young science superstar!

It all started when her back was up against the wall to submit her School Based Assessment (SBA), scores from which are added to make up the overall result for the Caribbean Secondary Education Certificate administered by the Caribbean Examinations Council. She had absolutely no idea what project she would undertake, and panic stepped in.

Her teacher, Sir Samuel McPherson, suggested that she give thought to things used in the community, and the light-bulb flashed in her head – Bambalayke!
Darshanie found that the Katahar flower contains a toxin called Sapanins, which kills mosquitoes and other insects, and that was effectively demonstrated when she lit up a dried flower.She then rummaged through writings of the Katahar plant (the scientific name: Artocarpus Camasi) on the Internet, and was able to set the theory of using the Katahar flower to make a repellent that could be used to keep mosquitoes and other insects out.

With her research completed, the SBA was submitted and she thought that was that. Not so fast, though. Sir McGarrell had other plans for her project.

The Regional Science, Mathematics and Technology Fair for schools was slated for early March at the Fort Wellington Secondary School, and Sir McPherson l thought it was a project she could expand on and present at the fair.

Darshanie enlisted the help of her classmate Dolly Sooknanan, 16, who completed her own project measuring the effect of salt on the temperature of the human body. And then there was also another helper, Mandy Mangru, 16, who worked out how fast a ball travels after it is hit by a player in the game of cricket.

For the fair, Darshanie had to make a mosquito coil and an insect repellent spray using the Sapanins extracted from the Katahar plant. Now to getting the materials to do it – the Katahar flower, sawdust, coconut shell dust, potato starch, coconut oil, rubbing alcohol, spiral form, spray bottles, and boxes.

Then they got to work. There were frustrating moments when the coil just would not bake! Darshanie and her friends are quick to admit that the tears of frustration flowed generously. In the end, they managed to invent both products, and it was time for the testing.

When it got dark, Darshanie and her friends would spread out a white cloth on the ground just below the light bulbs, where the mosquitoes and other insects would swirl. In the first five minutes of lighting up the coil, 20 mosquitoes fell, and then in another 22 minutes, another 81 mosquitoes met their death.

Watching them, her parents called the group a bunch of “mad scientists.” Darshanie’s inventions were ready for display at the fair, but Jaishree Nanku, a teacher just two years out of teacher’s training college, decided that they had to make an impression at the fair.

So she made sure that they had all the relevant display materials that would go along with the products, and sometimes they worked two to three hours past midnight to ensure that the display materials –- including labelling and cardboard writings explaining the process — were just how they wanted them.

On the day of the fair, Darshanie was a nervous wreck, but together with Dolly, they presented the project ably, and the project emerged the winner and was entered into the National Competition, which concluded on Friday.

Never in her wildest dreams did Darshanie think that this idea she thought up in a moment of panic would get all that attention, and she was completely caught off-guard when it was announced that the project had also won the national competition and secured the national prize from the Sagicor Visionaries Challenge, an initiative of the Caribbean Science Foundation (CSF), insurance company Sagicor Life Inc (Sagicor) and CXC to encourage innovation in science and technology solutions to the problems plaguing communities.

The Sagicor Visionaries Challenge is run across the Caribbean, and national winners participate in a 7-day, all-expenses-paid Science, Technology, Engineering and Mathematics (STEM) Ambassador Programme in Florida, USA. There, Darshanie will compete in the regional finals and get the opportunity to win US$5000 for the Bygeval school.

“I can’t explain how I feel,” Darshanie told the Sunday Chronicle.
“I am surprised, because when I saw some of the other projects, I didn’t think we would win. I guess the presentation is what did it for us.”

Going forward, Darshanie and others who worked with her on the project hope to gain approval to hand out samples to residents of Mahaica as part of a survey to test the effectiveness of the product, which they have branded The Eradicator.

President David Granger, speaking on Friday at the National Fair in Linden, said Guyana needs an “education of innovation” to meet its limitless needs, and youths must be provided with opportunities to develop practical solutions to ensure that those needs are adequately met.

“These exhibitions of the creative genius of our students reassure that our country’s future will be guided by a generation of fine minds. They remind us constantly that the future of this country will be in safe hands,” President Granger said.

He urged students and teachers to ensure that their innovations are expanded upon beyond the fair, so that they can lead to positive, life-changing benefits for the wider Guyanese society.

“The models of the projects on display could be shared with the wider society, so that their practical applications would not be completely lost, but would add value to people’s lives.

“Your enthusiastic participation is a signal of your seriousness, not only about success in your personal careers, but about solving problems in your communities and in this great country. It is the start of an innovation education,” the President said.

“Guyana faces threats from various sources: the adverse effects of climate change; concerns over the sustainability of our water supplies; the security of food supply; the generation of cheaper, cleaner and renewable sources of energy; and, inevitably, the prevention of the spread of diseases, such as Ebola and Zika, across borders.  The response to these global challenges requires scientific solutions,” the President said.

The Government has committed to providing 15 STEM scholarships for studies at the University of Guyana.

Among the prizes received by the winning school are a computerised mobile science and technology centre, six CXC-approved science kits, a Challenge Trophy, an award certificate, US$1000, GoPro cameras and Samsung smart watches for each member of the team, and a Kindle Fire tablet for the supervising teacher.

Darshanie and her team believe that the benefits to be gained from expanding the project are many. The implementation of the project on a commercial scale will encourage the community to plant more of the Katahar trees, in order to have a large quantity of the flowers to make the repellent. Apart from the repellent, the community will benefit from the supply of the Katahar to use for cooking, and the organic matter from the leaves of the trees could be used as mulch.

Darshanie and team say The Eradicator coil and spray does not affect the human skin.

The Pesticides and Toxic Chemicals Control Board recently warned against a number of coils that are illegal in Guyana and may pose serious dangers to the health of people who use them. Some of the coils not approved for use in Guyana are Lion Brand, Lizi and Goldee.

Source: Guyana Chronicle