LE3 .A278 2022

2022

Faraone, Nicoletta

Acadia University

Bachelor of Science

Honours

Chemistry

Chemistry

The incidence of reported tick-borne diseases has been increasing rapidly over recent years due to rising global temperatures. Because of this it is becoming important to manage tick populations and prevent bites to decrease transmission of these diseases and consequently pressure on public health systems. Recently, there has been a push towards utilizing plant extracts and essential oils as pest management tools since they are readily available, considered generally safe, and environmentally friendly. Because of their chemical nature, plant extracts and essential oils have a low environmental persistency and are easily degradable. To protect their properties and extend their longevity, different approaches have been explored, such as encapsulation and protection of the active ingredients with coating materials. In this work the mortality rates of nanoparticles synthesized with the plant extracts of garlic (Allium sativum L.) and yarrow (Achillea millefolium L.) were evaluated and compared to the mortality rates of encapsulated garlic essential oil particles against Ixodes scapularis ticks. Zinc oxide particles synthesized from both plant extracts through the green synthesis approach were found to have no effect on tested ticks. The LD50 of garlic essential oil was calculated to be 2.26 % v/v (95% CI: 2.31-2.21). Therefore, 2% (w/w) garlic oil was encapsulated in gum Arabic and maltodextrin with efficiencies ranging from 38 – 60%. The highest oil retention was observed for the garlic oil encapsulated in gum Arabic which had a mortality rate of 24 ± 8.7% against I. scapularis adult females seven days after exposure. These results indicated that garlic essential oil encapsulated in gum Arabic is a promising tick management tool.

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https://scholar.acadiau.ca/islandora/object/theses:3797