RESUMEN

In Brazil, the use of Eucalyptus is focused on the production of wood or pulp for the paper industry but without any general recovery of waste, with leaves and branches being left on the ground. One possibility is to use these residues as raw materials in the production of industrially relevant and value-added compounds such as essential oil. The aim of the present study was to investigate the chemical composition, yield, anti-inflammatory/antinociceptive activities, and acute toxicity in mice, as well as the antimicrobial effects of essential oils from the leaves of 7 varieties of Eucalyptus and hybrids against Escherichia coli, Staphylococcus aureus, and Candida albicans. The extraction of oils was carried out using hydrodistillation, and they were analyzed by gas chromatography coupled to mass spectrometry. Urocam and Grancam were the plants that obtained the highest oil yield, with yields of 3.32 and 2.30%, respectively. The main chemical components identified in these plants were 1.8 cineole and α-pinene. The antinociceptive effect of the 7 oils (50 mg/kg, p.o.) was initially assessed in the acetic acid-induced writhing test. In this assay, a significant (p < 0.05) antinociceptive/anti-inflammatory effect was observed from 4 tested essential oils (E. benthamii, E. saligna, and the hybrids Urocam and Grancam) when compared to the vehicle-treated group. This effect was then confirmed in the formalin-induced paw licking test. No toxicological effects or alterations were observed in motor coordination after the administration of the studied oils to the animals. In the antimicrobial evaluation, the seven essential oils inhibited the growth of S. aureus, E. coli, and C. albicans at different concentrations. Collectively, these results demonstrate that the essential oil from the leaves and branches of Eucalyptus species and varieties present potential biomedical applications and represent a source of antimicrobial and/or anti-inflammatory compounds.

RESUMEN

English is the lingua franca for scientific communication, but some journals, especially in developing countries, still publish non-English studies. A shift towards publishing in English may promote internationalization and more visibility of scientific journals. Here we compared quality indexes between Brazilian journals that have always published in English and journals that have published in languages other than English. We also investigated whether a temporal shift towards publishing in English led to elevated quality measures. Our analyses covered 16 Brazilian biodiversity journals and accounted for 12640 papers published since 2007. The mean impact factor was on average 55% higher in journals that have published consistently in English, compared to the so-called multilanguage journals. The proportion of publications in English increased to nearly three times the original value in multilanguage journals between 2007 and 2016, and the impact factor tripled during this period. At the same time, the Qualis-Capes classifications (B1-B2-B3) tended to fall. Publishing in English can be a first step to increased visibility, and this is particularly important for biodiversity journals, since Brazilian ecosystems are considered of interest to the international scientific community and nature conservation.

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RESUMEN

The objective was to assess the effects of natural variation in the physical structure of the environment on biological communities and on the processing of Eucalyptus cloeziana and Inga laurina and to identify the controlling factors at different scales along stream order gradients. The study area consisted of 14 sampling sites distributed within a tropical watershed (1st, 2nd, 3rd and 4th order streams replicated in 4 sub-basins). Our samples consisted of 3 g of leaves of E. cloeziana (high-quality) and I. laurina (low-quality) placed in 252 bags with 10mm mesh (measured by the chemical composition of the detritus). Four samples of each leaf type were collected periodically (three times) over a period of 75-125 days and washed on a sieve to separate the invertebrates. A series of leaf disks were cut to determine ash-free dry mass, polyphenol, lignin, cellulose, total microbial biomass and fungal biomass, and the remaining material was oven-dried to determine the dry weight. We performed analyses within and between spatial scales (regional and local) to assess which watershed scale was the more import determinant of the leaf breakdown rate (k). The microbial and shredder were most influenced at the local scale (stream order). Shredders were influenced by microorganisms, with stronger interactions between them than were found to drive the k at the local scale. Moreover, differences in the overall k and abiotic variables were more strongly influenced at the regional scale (sub-basin), showing that the study scale alters the response of the studied variables. We found higher k values at higher values of water velocity, dissolved oxygen and temperature, all of which accelerate biological metabolism in response to variations on the regional scale. Watersheds with warmer microclimates and streams with higher nutrient levels and oxygen could be accelerating the ecosystem metabolism, independent of the detritus quality.

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