Better than DEET Repellent Compounds Derived from Coconut Oil

Area of Science:

• Entomology
• Organic Chemistry
• Public Health

Background:

• Hematophagous arthropods transmit pathogens, causing significant global disease burden and mortality.
• N,N-Diethyl-meta-toluamide (DEET) is a widely used repellent but has associated health concerns, especially for vulnerable populations.
• There is a need for safe, effective, and affordable arthropod repellents.

Purpose of the Study:

• To identify and evaluate novel repellent compounds derived from coconut oil.
• To assess the efficacy and spectrum of activity of these coconut fatty acids against various blood-sucking arthropods.
• To compare the repellent activity of coconut fatty acids with DEET and evaluate a natural repellent formulation for livestock.

Main Methods:

• Laboratory bioassays were conducted to test the repellent activity of medium-chain fatty acids (C8:0 to C12:0) from coconut oil against biting flies, bed bugs, ticks, and mosquitoes.
• Residual activity was assessed over time post-application.
• An aqueous starch-based formulation containing coconut fatty acids was tested on cattle for protection against biting flies under field conditions.

Main Results:

• Coconut fatty acids, particularly C8:0 to C12:0, demonstrated significant repellent activity against a broad range of arthropods.
• Repellency against biting flies and bed bugs lasted for two weeks, and against ticks for one week, outperforming DEET in duration and strength.
• The natural repellent formulation protected cattle from biting flies for up to 96 hours, representing the longest documented protection for a natural repellent.

Conclusions:

• Coconut fatty acids are potent, broad-spectrum arthropod repellents with superior efficacy and residual activity compared to DEET.
• These natural compounds offer a safe, cost-effective, and sustainable alternative for personal protection and livestock management.
• Further development of coconut fatty acid-based repellents holds promise for reducing the impact of vector-borne diseases.