Fusarium begoniae metabolites: a promising larvicidal, pupicidal potential, histopathological alterations and detoxifications enzyme profiles of medically important mosquito vector Aedes aegypti, Culex quinquefasciatus and Anopheles stephensi

Abstract

Endophytic fungal molecules have the potential to be a cost-effective chemical source for developing eco-friendly disease-controlling pharmaceuticals that target mosquito-borne illnesses. The primary aims of the study were to identify the fungus Fusarium begoniae larvicidal ability against Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi. The ethyl acetate extract demonstrated lethal concentrations that kill 50% of exposed larvae (LC₅₀) and 90% of exposed larvae (LC₉₀) for the 1st to 4th instar larvae of An. stephensi (LC₅₀ = 54.821, 66.525, 68.250, and 73.614; LC₉₀ = 104.56, 138.205, 150.415, and 159.466 μg/mL), Cx. quinquefasciatus (LC₅₀ = 64.981, 36.505, 42.230, and 36.514; LC₉₀ = 180.46, 157.105, 140.318, and 153.366 μg/ mL), and Ae. aegypti (LC₅₀ = 74.890, 33.607, 52.173, and 26.974; LC₉₀ = 202.56, 162.205, 130.518, and 163.286 μg/mL). Mycelium metabolites were evaluated for their pupicidal activity towards Ae. aegypti (LC₅₀ = 80.669, LC₉₀ = 119.904), Cx. quinquefasciatus (LC₅₀ = 70.569, LC₉₀ = 109.840), and An. stephensi (LC₅₀ = 73.269, LC₉₀ = 110.590 μg/mL). The highest larvicidal activity was recorded at 300 µg/mL, with 100% mortality against first and second-instar larvae of Cx. quinquefasciatus. Metabolite exposure to larvae exhibited several abnormal behavioral changes. The exposure to F. begoniae metabolite, key esterases such as acetylcholinesterase, α-and-β-carboxylesterase, and acid and alkaline phosphatase activity significantly decreased compared to control larvae. The outcomes of the histology analysis revealed that the mycelium metabolites-treated targeted larvae had a disorganized abdominal mid and hindgut epithelial cells. The is first-hand information on study of ethyl-acetate-derived metabolites from F. begoniae tested against larvae and pupae of Ae. aegypti, Cx. quinquefasciatus and An. stephensi. Bio-indicator toxicity findings demonstrate that A. nauplii displayed no mortality.