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Botanical biopesticides have emerged as sustainable and eco-friendly alternatives to synthetic pesticides, whose indiscriminate use leads to several drawbacks to human and environmental health. To the best of our knowledge, there have been no reports on M. pubescens’ bioactivity on phytopathogens affecting crops as a potential fungicide or antifeedant. This has encouraged us to investigate the potential of the roots of this plant as a source of biopesticides. The present study reports on the evaluation of the roots extract from Magonia pubescens A. St.-Hill., a species from the Cerrado (Brazilian savannah), on the phytopathogenic fungi Botrytis cinerea, Fusarium oxysporum, and Alternaria alternata. In addition, its insect antifeedant effect was assayed against Chrysodeixis chalcites. Thus, an in vitro test-assay was used to determine the fungicide potential (percentage growth inhibition, % GI) of the ethanolic extract of this plant species, whereas a leaf-disk bioassay on the 5th instar larvae of C. chalcites was performed to evaluate its insecticidal potential. The ethanolic extract was further fractionated by liquid–liquid partition using solvents of increasing polarity. The hexane/dichloromethane fraction exhibited a moderated potency and was similar to the ethanolic extract on the three assayed fungi (around % GI 30 at 1 mg/mL), whereas the n-butanol fraction showed a slight improvement of the fungicide effect against B. cinerea (% GI 39.18 at 1 mg/mL). Moreover, the ethanolic extract exhibited a strong antifeedant activity, with a refusal rate (FR) higher than 90% in both choice and non-choice assays against C. chalcites, while the ethyl acetate and n-butanol fractions behaved as appetite suppressors. These results highlight M. pubescens as a promising source of biopesticides and deserve further investigations to optimize extraction procedures. Full article

Higher food intake promotes obesity, a critical public health challenge with increasing prevalence worldwide. Selective modulators of appetite can be applied as therapeutic intervention. Nevertheless, currently the appetite suppressant drugs trigger severe side effects, such as anxiety and depression. For that reason, there is a priority to discover new pharmaceuticals. In this study, a library of 117 cyanobacterial fractions from marine and freshwater environments belonging to The Blue Biotechnology and Ecotoxicology Culture Collection (LEGE-CC) of CIIMAR (Interdisciplinary Centre of Marine and Environmental Research) were screened for their ability to interfere in the food intake behavior of zebrafish larvae—a whole small animal model. Two different bioassays were performed for appetite-reducing activity, using fluorescent stained liposomes (passive food intake) or Paramecia bursaria (active food intake). Three cyanobacterial fractions from the order Nostocales, Chroococcidiopsidales and Pleurocapsales expressed appetite-suppression bioactivity in the liposomes assay, while three different fractions from the order Synechococcales, Oscilatoriales and Nostocales significantly reduced the appetite in the Paramecium assay. To highlight putatively associated metabolites for the bioactivities, dereplication by metabolomics approaches (LC-MS/MS) was performed, as well as a bioactivity-guided feature-based molecular networking using GNPS, and four compounds were positively correlated to the bioactivity. No matches were found in any database for these molecules, indicating putatively new compounds. Molecular analyses are currently ongoing to discover the involved genes that regulate the passive and active food intake in zebrafish larvae, and consequently uncover the mechanisms of action. Full article