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Lauraceae species are known as excellent essential oil (EO) producers, and their taxa are distributed throughout the territory of Brazil. This study presents a systematic review of chemical composition, seasonal studies, occurrence of chemical profiles, and biological activities to EOs of species of Licaria, Nectandra, and Ocotea genera collected in different Brazilian biomes. Based on our survey, 39 species were studied, with a total of 86 oils extracted from seeds, leaves, stem barks, and twigs. The most representative geographic area in specimens was the Atlantic Forest (14 spp., 30 samples) followed by the Amazon (13 spp., 30 samples), Cerrado (6 spp., 14 samples), Pampa (4 spp., 10 samples), and Caatinga (2 spp., 2 samples) forests. The majority of compound classes identified in the oils were sesquiterpene hydrocarbons and oxygenated sesquiterpenoids. Among them, β-caryophyllene, germacrene D, bicyclogermacrene, caryophyllene oxide, α-bisabolol, and bicyclogermacrenal were the main constituents. Additionally, large amounts of phenylpropanoids and monoterpenes such as safrole, 6-methoxyelemicin, apiole, limonene, α-pinene, β-pinene, 1,8-cineole, and camphor were reported. Nectandra megatopomica showed considerable variation with the occurrence of fourteen chemical profiles according to seasonality and collection site. Several biological activities have been attributed to these oils, especially cytotoxic, antibacterial, antioxidant and antifungal potential, among other pharmacological applications.

Eugenia species are well known for their great economic potential as edible fruits. The leaves of 4 Eugenia biflora specimens (Ebi-1 to Ebi-4) were sampled in the Caratateua Island, Pará state, Brazilian Amazon. Then, the essential oils were hydrodistilled, analyzed by gas chromatography (GC) and GC mass spectroscopy, and their volatile compositions submitted to multivariate analysis (principal component analysis and hierarchical cluster analysis). Ebi-1 and Ebi-2 specimens were classified in the caryophyllene group, with significant content for the sesquiterpenes ( E)-caryophyllene (16.8% and 11.4%) and caryophyllene oxide (28.6% and 20.5%). Ebi-3 specimen was grouped into the cadinane group, characterized by the presence of α-cadinol (14.7%), an oxygenated sesquiterpene. EBI-4 specimen was inserted into the aromadendrane group, with the predominance of the sesquiterpenes globulol (9.8%), germacrene B (7.9%), and γ-elemene (3.1%). Based on the results, a remarkable chemical variability was observed in the oils of Eugenia biflora with occurrence in Pará state, North Brazil. This work is presenting for the first time its caryophyllene, cadinane, and aromadendrane profiles.

Peperomia pellucida L. Kunth is a herb well-known for its secondary metabolites (SM) with biological potential. In this study, the variations in the SM of P. pellucida during association with rhizobacteria were evaluated. Plants were inoculated with Enterobacter asburiae and Klebsiella variicola, which were identified by sequencing of the 16S rRNA gene. The data were evaluated at 7, 21, and 30-day post inoculation (dpi). Plant-bacteria symbiosis improved plant growth and weight. Total phenolic content and phenylalanine ammonia lyase enzyme activity had a significant increase mainly at 30 dpi. P. pellucida was mainly composed of phenylpropanoids (37.30–52.28%) and sesquiterpene hydrocarbons (39.28–49.42%). The phenylpropanoid derivative 2,4,5-trimethoxy-styrene (ArC2), the sesquiterpene hydrocarbon ishwarane, and the phenylpropanoid dillapiole were the major compounds. Principal component analysis (PCA) of the classes and compounds ≥ 2.0% indicated that plants colonized by E. asburiae had a reduction in the content of sesquiterpene hydrocarbons and an increase in phenylpropanoids and derivatives. Plants treated with this bacterium also had an increase in the content of 2,4,5-trimethoxystyrene at 30 dpi. Plants inoculated with K. variicola had significant increases only in the content of the classes monoterpene hydrocarbons and ‘other compounds’ (hydrocarbons, esters, ketones, etc.). These data suggest that the production of plant secondary metabolites can be modified depending on the type of rhizobacteria inoculated.

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