Eco-friendly synthesis of palladium nanoparticles using Zaleya decandra: Assessing mosquito larvicidal activity, zebrafish embryo developmental toxicity, and impacts on freshwater sludge worm Tubifex tubifex

Abstract

The transmission of various infectious diseases, by Aedes aegypti and Anopheles stephensi has poses a menace to human well-being. To combat the vector of this serious disease, environmentally friendly prevention strategies are essential. The fight against malaria and dengue is greatly aided by nanotechnology and pharmacology. The aqueous leaf extract of Zaleya decandra was used in the present study to synthesise palladium nanoparticles (Zd-PdNPs) by simple and sustainable processes. Numerous physiochemical methods were used to identify and classify bio-synthesized Zd-PdNPs. Additionally, Ae. aegypti and An. stephensi IV instar larvae were tested toxicity using Z. decandra extract and Zd -PdNPs. Further research was conducted to determine how the NPs-based treatment affected the histology and morphology of mosquito larvae. The LC50 values of ZD-PdNPs against Ae. aegypti larvae were 18.071 and 14.124 µg/mL; An. stephensi had 12.140 and 10.118 µg/mL at 12 and 24 hr exposure. Furthermore, zebrafish embryo developmental toxicity and the freshwater sludge worm Tubifex tubifex have both been utilised as test models for non-target eco-toxicological investigations in the typical laboratory setting. Gas chromatography-mass spectrometry was used to examine the chemical constituents of Z. decandra. n-hexadecanoic acid, 6-octadecenoic acid, phthalic acid, butyl undecyl ester, squalene, nonanoic acid, methyl ester, and butyl undecyl ester 2-methyl-4-phenylthiolane were identified as potential compounds for bio reduction and synthesis of nanoparticle. The current study reveals that natural molecules bonded nanomaterial that are effective against human disease spreading mosquito vectors larvae and highlights the potential value of Nano-larvicides as well as environmental safety.