Ecotoxicological evaluation of an aqueous phytoextract of Melia azedarach L

• Published in: The Science of the total environment Vol. 950; p. 175314
• Main Authors: Popescu, Vlad Sebastian, Zhang, Leilei, Papa, Giulia, Giuliani, Claudia, Ribaudo, Giovanni, Abate, Giulia, Bulgari, Daniela, Mac Sweeney, Eileen, Pucci, Mariachiara, Bottoni, Martina, Milani, Fabrizia, Zizioli, Daniela, Negri, Ilaria, Gianoncelli, Alessandra, Gobbi, Emanuela, Uberti, Daniela, Lucini, Luigi, Memo, Maurizio, Fico, Gelsomina, Peron, Gregorio, Mastinu, Andrea
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 10.11.2024
• Subjects: Environmental impact; Germination tests; Natural insecticides; Toxic phytochemicals; Toxicity assays; Zebrafish; Toxic phytochemicals; Zebrafish; Toxicity assays; Germination tests; Environmental impact; Natural insecticides
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.175314

Melia azedarach L. is a Meliaceae that has shown important insecticidal activities. However, few researchers have extensively studied the toxicology of aqueous extracts of M. azedarach (MAE). Therefore, the main objective of this study was to characterize the phyto-eco-toxicological profile of MAE. First, a botanical and phytochemical characterization of MAE was performed using a histological, and metabolomic multi-analytical approach. Second, the toxicological effects on pollinating insects (Apis mellifera ligustica) and soil collembola (Folsomia candida) were evaluated. In addition, acute toxicity was evaluated in zebrafish (Danio rerio) to assess effects on aquatic fauna, and toxicity was determined in human neuroblastoma (SH-SY5Y) and fibroblast (FB-21) cell models. Finally, phytotoxic effects on germination of Cucumis sativus L., Brassica rapa L. and Sorghum vulgare L. were considered. Metabolomic analyses revealed the presence of not only limonoids but also numerous alkaloids, flavonoids and terpenoids in MAE. Histological analyses allowed us to better localize the areas of leaf deposition of the identified secondary metabolites. Regarding the ecotoxicological data, no significant toxicity was observed in bees and collembola at all doses tested. In contrast, severe cardiac abnormalities were observed in zebrafish embryos at concentrations as low as 25 μg/mL. In addition, MAE showed toxicity at 1.6 μg/mL and 6.25 μg/mL in FB-21 and SH-SY5Y cells, respectively. Finally, MAE inhibited seed germination with inhibitory concentrations starting from 5.50 μg/mL in B. rapa, 20 μg/mL in S. vulgare, and 31 μg/mL in C. sativus. Although M. azedarach extracts are considered valuable natural insecticides, their ecological impact cannot be underestimated. Even the use of an environmentally friendly solvent (an aqueous solution), for the first time, is not without side effects. Therefore, the data collected in this study show the importance of evaluating the dosages, modes of administration and production methods of M. azedarach phytoextracts in agricultural settings. [Display omitted] •Melia azedarach extract (MAE) demonstrated cytotoxic effects on both human fibroblasts and neuroblastoma cells.•Danio rerio embryos exposed to high concentrations of MAE exhibited mortality and significant alterations.•MAE significantly inhibited seed germination and root elongation in three plant species: Brassica rapa, Sorghum vulgare, and Cucumis sativus.•No toxic effects were observed in Apis mellifera and Folsomia candida subjected to chronic exposure to MAE.