The Design of a Plant-Based Biopesticide Formulation with Extracts and Derivatives Containing Naphthoquinones

This study aimed to determine the antifungal activity of various compounds and develop a novel antifungal formulation against fungal pathogens, including Alternaria alternata, Botrytis cinerea, Penicillium expansum, and Rhizopus stolonifer. A total of 32 plant-derived secondary metabolites and three extracts (dichloromethane, ethyl acetate, and methanol) from Lawsonia inermis, Juglans regia, and Drosera intermedia were screened at a concentration of 250 ppm. The chemical composition of the D. intermedia ethyl acetate extract was characterized using chromatographic techniques. Subsequently, an emulsifiable concentrate formulation from this extract was prepared, and its efficacy was evaluated at concentrations ranging from 250 to 2000 ppm. The D. intermedia ethyl acetate extract was found to contain three flavonoids (1.4%) and three naphthoquinones (2.8%). The formulation exhibited optimal effect at 1000 ppm. Overall, the high efficacy of the formulation containing the dried D. intermedia extract (10:1, ethyl acetate) positions it as a promising and viable alternative to synthetic fungicides.