Due to the potential of phytochemicals as therapeutic agents, there is increased interest in plant compounds with this biological activity, such as the essential oils of medicinal and aromatic plants. This study assessed the antioxidant activity of essential oils from the species Croton grewioides and its major compounds (CGR106 and CGR126 – 29.51% and 42.68% of eugenol; CGR126 and CGR112 – 45.97% and 85.58% of methyl eugenol; CGR106 – 59.85% of methyl chavicol). Antioxidant activities were evaluated by the systems 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2ʹ-azinobis (3-ethylbenzoathazoline-6-sulfonic acid) (ABTS), Ferric Reducing Ability (FRAP) and co-oxidation of β-carotene/linoleic acid. The best results were found in the essential oils CGR106 and CGR126, from C. grewioides. Samples with eugenol in their composition showed greater free-radical stabilization capacity. Essential oils of both accessions presented antioxidant capacity in the methods tested.

Leaf-cutting ants are pests of great economic importance due to the damage they cause to agricultural and forest crops. The use of organosynthetic insecticides is the main form of control of these insects. In order to develop safer technology, the objective of this work was to evaluate the formicidal activity of the essential oils of two Hyptis pectinata genotypes (chemotypes) and their major compounds on the leaf-cutting ants Acromyrmex balzani Emery and Atta sexdens rubropilosa Forel. Bioassays of exposure pathways (contact and fumigation) and binary mixtures of the major compounds were performed. The major compounds identified in the essential oils of H. pectinata were β-caryophyllene, caryophyllene oxide and calamusenone. The essential oils of H. pectinata were toxic to the ants in both exposure pathways. Essential oils were more toxic than their major compounds alone. The chemotype calamusenone was more toxic to A. balzani in both exposure pathways. A. sexdens rubropilosa was more susceptible to the essential oil of the chemotype β-caryophyllene in both exposure pathways. In general, the binary mixtures of the major compounds resulted in additive effect of toxicity. The essential oils of H. pectinata is a raw material of great potential for the development of new insecticides.

The aim of this study was to perform chemical characterization of Lippia alba accessions from the Active Germplasm Bank of the Federal University of Sergipe. A randomized block experimental design with two replications was applied. The analysis of the chemical composition of the essential oils was conducted using a gas chromatograph coupled to a mass spectrometer. The chemical composition of the essential oils allowed the accessions to be allocated to the following six groups: group 1: linalool, 1,8‐cineole, and caryophyllene oxide; group 2: linalool, geranial, neral, 1,8‐cineol, and caryophyllene oxide; group 3: limonene, carvone, and sabinene; group 4: carvone, limonene, g‐muurolene, and myrcene; group 5: neral, geranial, and caryophyllene oxide; and group 6: geranial, neral, o‐cymene, limonene, and caryophyllene oxide.