The phenolic profiles of cabbage white butterfly (Pieris brassicae L.; Lepidoptera: Pieridae) at different development stages (larvae, exuviae, and butterfly), its excrements, and its host plant Brassica rapa
var. rapa L. were determined by high performance liquid chromatography- diode-array detector-mass
spectrometry/mass spectrometry-electrospray ionization (HPLC-DAD-MS/MS-ESI). Twenty-five
acylated and nonacylated flavonoid glycosides and ferulic and sinapic acids were identified in host
plant, from which only 12 compounds were found in the excrements. In addition, the excrements
showed the presence of sulfate flavonoids and other flavonoid glycosides that were not detected in
the leaves. In the larvae kept without food for 12 h, only 3 compounds common to the plant material
and 2 others, also present in the excrements, were characterized. The results indicate that deacylation,
deglycosylation, and sulfating steps are involved in the metabolic process of P. brassicae and that
its excrements may constitute a promising source of bioactive compounds, which could be used to
take profit of this common pest of Brassica cultures.
