Non-toxic larvicide

Inventors

Matthews, Scott • Durvasula, Ravi • Foo-Hurwitz, Ivy

Assignees

US Department of Veterans Affairs • UNM Rainforest Innovations

Abstract

An larvicide comprising an essential oil encapsulated within a non-viable yeast cell. The larvicide is particularly effective against mosquito larvae, non-toxic to humans and other non-target species, inexpensive to make, and non-toxic during manufacture, transport, and storage.

Core Innovation

The invention provides a novel insect larvicide that encapsulates an essential oil, such as lemongrass oil, within a non-viable yeast cell, particularly of the S. cerevisiae variety. This larvicidal capsule acts specifically when ingested by pest insect larvae, such as mosquito larvae, delivering the larvicidal element directly to the target species while being non-toxic to humans and other non-target species. The yeast cell serves as an ingestible delivery vehicle, sequestering the essential oil from the environment until digestion by the larvae liberates the larvicidal agent to exert its effect.

The problem addressed by the invention involves the limitations and risks associated with traditional pest control methods. Conventional chemical pesticides are often harmful to humans, animals, and non-target species and pose hazards during manufacture, transport, and storage. Additionally, essential oils, while effective larvicides, require large repeated dosages and are vulnerable to environmental degradation, disrupting aquatic environments and affecting non-target species. Existing alternatives like genetically modified insects are limited in application and carry unknown long-term risks. Thus, an effective, safe, inexpensive larvicide that targets larvae specifically and overcomes these challenges is highly desirable.

The larvicide disclosed is stable and safe during manufacture, transport, and storage due to the encapsulation within non-viable yeast cells, which irreversibly sequester the essential oil and prevent environmental exposure until ingestion by larvae. This approach allows for targeted delivery of the larvicidal substance, reducing environmental impact and non-target exposure. The larvicide can be modified for buoyancy control to target different larval feeding zones and coated with soluble materials for delivery via carriers such as female mosquitoes to oviposition sites. These innovations facilitate effective control of pest insect larvae, including mosquitoes, in diverse environments including potable water reservoirs, enhancing safety and efficacy.

Claims Coverage

The patent contains multiple independent claims describing larvicidal capsules and methods of forming them, focusing on encapsulation, coatings, and buoyancy control features.

The independent claims cover larvicidal capsules comprising essential oils encapsulated in non-viable yeast cells coated with soluble silica, methods for their formation, and incorporation of buoyancy control mechanisms using air pockets or adhesives to maintain desired positioning in water for effective larval targeting.

Stated Advantages

Documented Applications