Epsilon Archive for Student Projects

Abstract

Insects produce an epicuticle comprised of a complex mixture of hydrocarbons and closely related
chemical compounds, originally evolved as a mechanism to prevent desiccation but which
developed an additional role as a form of chemical fingerprint unique to the species in question. This
is useful as both intra- and interspecific communication, however the low volatility of these
hydrocarbons permits only short-range communication. One cuticular hydrocarbon produced by
Drosophila melanogaster females is (Z,Z)-7,11-heptacosadiene, may be spontaneously oxidized at
its double bonds. One possible oxidation product is (Z)-4-undecenal, which has recently been shown
to function as a long-range pheromone owing to its higher volatility as compared to its hydrocarbon
precursor. The aim of this study is to investigate the effects on (Z)-4-undecenal production by
ultraviolet light.
This involves investigating different sampling durations of (Z)-4-undecenal, as well as
irradiating both synthetic (Z,Z)-7,11-heptacosadiene and live D. melanogaster females. Headspace
collection is done through solid phase microextraction, and subsequent analysis with gas
chromatography-mass spectrometry.
Due to the variability in the results, it was not possible to verify the hypothesis that ultraviolet
light increases production of (Z)-4-undecenal in D. melanogaster, however the study did provide
insights as to which experimental parameters could be modified in future research. Some suggestions
are provided.