Malaria is an infectious disease caused by Plasmodium spp. and it is mainly transmitted to humans by female mosquitoes of the genus Anopheles. Malaria is an important global public health problem due to its high rates of morbidity and mortality. At present, drug therapies and vector control with insecticides are respectively the most commonly used methods for the treatment and control of malaria. However, several studies have shown the resistance of Plasmodium to drugs that are recommended for the treatment of malaria. In view of this, it is necessary to carry out studies to discover new antimalarial molecules as lead compounds for the development of new medicines. In this sense, in the last few decades, animal venoms have attracted attention as a potential source for new antimalarial molecules. Therefore, the aim of this review was to summarize animal venom toxins with antimalarial activity found in the literature. From this research, 50 isolated substances, 4 venom fractions and 7 venom extracts from animals such as anurans, spiders, scorpions, snakes, and bees were identified. These toxins act as inhibitors at different key points in the biological cycle of Plasmodium and may be important in the context of the resistance of Plasmodium to currently available antimalarial drugs.

Essential oils from Amazonian species are gaining increasing interest worldwide due to their medicinal and cosmetic applications; however, the relation among the chemical constituents and their biological properties are not well explored. Therefore, the present research aims to obtain an understanding of the bioactivity of chemical compounds in the essential oils of plants from the Annonaceae family (Bocageopsis pleiosperma, Onychopetalum amazonicum, Unonopsis duckei, U. floribunda, U. rufescens, U.stipitata, U. guatterioides, Duguetia flagellaris and Xylopia benthamii). By means of gas chromatography coupled to mass spectrometry, in vitro cytotoxic and anti-lipase assays, principal component analysis and molecular docking, it was possible to establish the main compounds that may be responsible for the cytotoxic effect of O. amazonicum and B. pleiosperma. Moreover, the anti-lipase potential of D. flagellaris was also established, as well as its composition related to the activity. Thus, by the employed strategy, allo-aromadendrene, cryptomerione, δ-cadinene and β-bisabolene were suggested as plausible cytotoxic agents against cancer cell lines, and dehydroaromadendrene, spathulenol and elemol, against lipase. The present study provides significant information on the chemical profile and bioactivity studies of Amazon Annonaceae aromatic plants.

Extracts made from the skin of dead Lithodytes lineatus frog individuals with the application of the benzocaine-based anesthetic gel, introduced into the oral cavity, were analyzed by ¹H Nuclear Magnetic Resonance to investigate whether the application of this product (oral) can make studies that use extracts from the skins of these animals unfeasible. For comparison, we used skins of another species of anuran following the same death protocol. No trace of the benzocaine substance was found in the ¹H-NMR spectra of the skin extracts from any of the tested anuran species. Still, using the hierarchical clustering model, it was possible to observe the formation of well-defined groups between the skin extracts of anurans and the anesthetic used to kill these animals. Our results suggest that the lethal dose of benzocaine in gel used inside the mouth of frogs may have no influence on potential results regarding the chemical composition or even bioassays using extracts made from the skin of these animals killed under this protocol since there was no detection of this substance for the analyzed samples.

Aspidosperma excelsum Benth. (Apocynaceae) is an Amazonian medicinal species traditionally used for treating malaria, inflammatory disorders, liver diseases, fever, and other health conditions. Despite growing scientific interest, knowledge regarding this species remains fragmented and complicated by taxonomic inconsistencies involving botanical synonyms. The present review critically compiled and integrated the available evidence regarding A. excelsum and its validated synonyms, emphasizing taxonomic aspects, ethnomedicinal applications, phytochemical composition, and pharmacological potential. Taxonomic standardization was performed using the Plants of the World Online database, and systematic literature searches identified 45 eligible studies after applying explicit search and eligibility criteria. Ethnobotanical evidence highlighted the widespread traditional use of stem bark preparations, particularly for malaria treatment across Amazonian communities. Phytochemical investigations revealed a remarkable diversity of indole alkaloids, alongside flavonoids, tannins, and terpenoids, reinforcing the species as a promising source of bioactive metabolites. Experimental studies demonstrated antiplasmodial, anti-inflammatory, antimicrobial, antioxidant, antileishmanial, and selective cytotoxic activities, partially supporting traditional therapeutic indications and suggesting convergence between ethnomedicinal knowledge and pharmacological evidence. However, most findings derive from in vitro and preclinical studies. This review consolidates fragmented information, addresses nomenclatural inconsistencies, and establishes a framework to guide future pharmacological investigations.