Enhanced repellency of binary mixtures of Zanthoxylum piperitum pericarp steam distillate or Zanthoxylum armatum seed oil constituents and Calophyllum inophyllum nut oil and their aerosols to Stomoxys calcitrans

摘要

BACKGROUND: The repellency to stable fly, Stomoxys calcitrans (L.), of Zanthoxylum piperitum (L.) DC pericarp steam distillate (ZP-SD), Zanthoxylum armatum DC seed oil (ZA-SO) and their constituents alone or in combination with Calophyllum inophyllum L. nut oil (CI-NO), as well as six aerosol formulations containing ZP-SD or ZP-SO and Cl-NO, was compared with that of a synthetic repellent, DEET, using an exposed human hand bioassay.RESULTS: At 0.20 mg cm~(-2), ZP-SD treatments resulted in 91 and 68% repellency following 30 and 60 min exposure respectively, while DEET gave 100 and 84% repellency. ZA-SO was less effective than ZP-SD. At 0.2 mg cm~(-2), the most active constituents, cuminaldehyde, cuminyl alcohol, limonene and methyl cinnamate, gave 82,74, 74 and 64% repellency at 30 min respectively, but DEET gave 100 and 87% repellency at 30 and 60 min. An increase in effectiveness and duration of repellency was produced by binary mixtures of ZP-SD, ZA-SO or bioactive constituents (each 0.01 mg cm~(-2)) and Cl-NO (0.99 mg cm~(-2)). The repellency of aerosols containing 2.5% ZP-SD or 2.5% ZA-SO and 2.5% Cl-NO was comparable with that of 5% DEET aerosol.CONCLUSION: Mixtures formulated from ZP-SD, ZA-SO or bioactive constituents and Cl-NO could be useful as potential repellents for the control of stable fly populations in light of global efforts to reduce the level of highly toxic synthetic repellents.