Correlation of probiotic synthesis nanoparticles against rift valley fever vector, Culex antennatus becker (Diptera: Culicidae)

Application of Probiotic bacteria for biosynthesis of nanoparticles could be a good ecofriendly alternative to chemical and physical method. The present research was pointed to the biosynthesis of silver (AgNPs) and cooper (CuNPs) nanoparticles using Lactobacillus reuteri and evaluating their effect against Rift Valley Fever Vector, Culex antennatus Becker (Diptera: Culicidae). The cell free supernatant of Lactobacillus reuteri was used for silver and copper nanoparticle biosynthesis from AgNO₃ and CuSO₄ solutions. The NPs production were confirmed and characterization by UV-visible spectroscopy and transmission electron microscopy analysis. TEM images were used for determination NPs size, shape and distribution of nanoparticles. Results confirmed that AgNPs and CuNPs from Lactobacillus reuterishowed larvicidal activity against mortality of Culex antennatus 3^rd larval instar recorded 98.67 and 89.33% by AgNPs and CuNPsat 500 μM, respectively. Lethal concentrations (LC₂₅, LC50 and LC₇₅) of AgNPs and CuNPs prolonged C. antennatus both larval and pupal times as compared with untreated groups. Also, AgNPs and CuNPssignificantly decreased the mean number of eggs laid by females resulted from treated larvae. At LC₇₅ of AgNPs and CuNPs, number of eggs laid by females recorded 39.91 and 52.10 eggs/±, respectively vs. 104.13 eggs/± for the control.The highest sterility index (91.87 and 78.21%) attained by LC₇₅ of AgNPs and CuNPs, respectively. Generally, AgNPs was more effective against tested larvae, as well as reproductive potential of resulted females than CuNPs.