Malathion ELISA Kit

BACKGROUND The oriental fruit fly,Bactrocera dorsalis(Hendel), is a widespread agricultural pest that has evolved resistance to many commonly used insecticides including malathion. GlutathioneS-transferases (GSTs) are multifunctional enzymes that metabolize insecticides directly or indirectly. The specific mechanism used by GSTs to confer malathion resistance inB. dorsalisis unclear. RESULTS BdGSTd9was identified fromB. dorsalisand was expressed at twice the level in a malathion-resistant strain (MR) than in a susceptible strain (MS). By using RNAi ofBdGSTd9, the toxicity of malathion against MR was increased. Protein modelling and docking of BdGSTd9 with malathion and malaoxon indicated key amino acid residues for direct binding in the active site.In vitroassays with engineered Sf9 cells overexpressing BdGSTd9 demonstrated lower cytotoxicity of malathion. High performance liquid chromatography (HPLC) analysis indicated that malathion could be broken down significantly by BdGSTd9, and it also could deplete the malathion metabolite malaoxon, which possesses a higher toxicity toB. dorsalis. Taken together, the BdGSTd9 ofB. dorsaliscould not only deplete malathion, but also react with malaoxon and therefore enhance malathion resistance. CONCLUSION BdGSTd9is a component of malathion resistance inB. dorsalis. It acts by depleting both malathion and malaoxon. (c) 2020 Society of Chemical Industry

Wastewater stabilisation ponds are the simplest, and most economical and maintainable way of municipal wastewater treatment. The fate of selected emerging contaminants using algal monocultures has been studied. However, in an actual wastewater treatment plant, it is likely to be different. Accordingly, a need was felt to take up this study. A waste stabilisation pond based wastewater treatment plant having five ponds in an area of approximately 14 hectares and working for 30 years was selected. High removal (> 75%) was observed in the case of paracetamol and carbaryl. Moderate removal efficiencies (50-75%) were found for malathion, erythromycin, clofibric acid and 17beta-estradiol while low (< 50%) removal efficiencies were witnessed in the case of aldrin, endosulfan, dichlorodiphenyltrichloroethane, hexachlorocyclohexane and diclofenac. Results show that most of the removal takes place in initial ponds, with higher efficiencies in summer and lower in winter. Results suggest that waste stabilisation pond based wastewater treatment plant is capable of removing emerging contaminants to some extent.