2024 AIChE Annual Meeting

Steam Distillation of Biomass for Insect Repellents

This study investigated the mosquito repellency of essential oils from hedge apples extracted by steam distillation. Hedge apples (Maclura pomifera) are also known as “Osage oranges” and can be found growing in the south-central U.S. Hedge apple trees are commonly planted as hedges due to the hardness and rot-resistance of the wood. The fruit can be eaten but usually is not because of the bitter taste. This study was inspired by the traditional practice of placing hedge apple fruits in outdoor areas to repel mosquitos.

Building on previous methods used for extraction of essential oils from guayule and hemp biomass, steam distillation was selected for extraction of essential oils from hedge apples. Chemical characterization will be used to identify compounds that have been found to be effective in mosquito repellency from previous experiments and related literature. To test the efficacy of the extracts against yellow fever mosquitoes (Aedes aegypti), an arm-in-cage assay will be conducted to observe the mosquitos’ behavior in the presence of these oils in an isolated environment. Some factors that need to be considered for the steam distillation extraction process include the parts of the fruit to be used, fruit ripeness, and changes during storage. This research will contribute to the understanding of the chemical composition of effective mosquito repellents, identification of alternative sources for these compounds, and development of pest management solutions.