Stability Challenges and Non-Target Effects of Mandelonitrile-Based Sugar Baits for Leishmaniasis Vector Control.

Area of Science:

• Vector-borne disease control
• Entomology
• Chemical ecology

Background:

• Leishmaniasis is a significant global health issue transmitted by sand flies.
• Attractive toxic sugar baits (ATSBs) offer a novel vector control strategy targeting adult sand fly feeding behavior.
• Mandelonitrile, a plant compound, demonstrates anti-Leishmania properties but requires evaluation for bait stability and ecological safety.

Purpose of the Study:

• To assess the stability of mandelonitrile in sucrose-based baits with preservatives.
• To quantify mandelonitrile degradation in high-sucrose matrices.
• To investigate the off-target effects of mandelonitrile on the model organism Drosophila melanogaster.

Main Methods:

• Sucrose solutions with methylparaben or sodium azide were tested for stability.
• Gas chromatography-mass spectrometry (GC-MS) was used to quantify mandelonitrile degradation.
• The impact of mandelonitrile on Drosophila melanogaster survival and reproduction was evaluated.

Main Results:

• Methylparaben and sodium azide stabilized sucrose baits for up to seven days, but negatively impacted sand fly survival.
• Mandelonitrile degraded rapidly, becoming undetectable within one week.
• Mandelonitrile exposure reduced longevity and inhibited oviposition in Drosophila melanogaster.

Conclusions:

• Mandelonitrile sugar baits require improved formulations to enhance stability and reduce degradation.
• The rapid degradation and observed off-target effects necessitate thorough ecological safety assessments.
• Further development is crucial for creating effective and environmentally sound transmission-blocking sugar baits for leishmaniasis control.