Nichinda leaves can combat dengue and filariasis
.jpg "Nichinda extracts attack larval gut (Source: Forest & Kim Starr)")
USE of insecticides to get rid of mosquitoes is known to be detrimental to the environment and human health. A finding on how larvae of mosquitoes which cause dengue and filariasis can be killed in an eco-friendly way, therefore, holds significance.
Researchers at the Annamalai University in Tamil Nadu have found the secret in the leaves of Nichinda tree (Vitex trifolia), a coastal shrub. Extracts of its leaves attack the gut of the larvae’s epithelial cell. Methyl-para-hydroxybenzoate present in the leaves accomplish this task.
In 2007, researchers had exposed the larvae of dengue- and filariasis-causing mosquitoes to the leaf extracts of different species of Vitex. It was the leaf extract of Nichinda that killed the larvae of both mosquitoes.
In the recent study, researchers found the compound in the leaf responsible for the larvicidal activity. They used different organic solvents to separate chemicals in the leaf extract. The fraction that had the maximum larvicidal activity was found to contain methyl-para-hydroxybenzoate.
Researchers have also isolated the crystalised form of methyl-para-hydroxybenzoate. “The compound has been reported in many plant species but its crystal structure was never isolated,” says lead researcher V Venkatesalu. Knowing the crystal structure will help identify the exact structure of methyl-para-hydroxybenzoate responsible for the leaf extracts’ larvicidal property.
The compound belongs to a class of organic compounds known as phenols. It can be used after further toxicological evaluations on non-target organisms, he adds. The study was published in the October-November issue of the journal Acta Tropica.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
.png)
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.