Abstract Plants synthesize secondary metabolites as a means of survival and competition. These metabolites are a potential source of natural antioxidants that may promote activity, favoring the control of cellular damage caused by oxidative stress. The Annonaceae family occurs in tropical and subtropical regions worldwide. The medicinal benefits of plants from this family are caused by secondary metabolites present in these species. Thus, this study aimed to determine the total phenolic content, evaluate the antioxidant potential, and in vitro cytotoxicity of the leaf ethanolic extract from Ephedrantus amazonicus R. E. Fries. The phenolic content and antioxidant activity were evaluated by the Folin-Ciocalteu and DPPH methods, respectively. The assays were adapted for 96-well microplates, with absorbance reading at λ = 630 and 517 nm, respectively, using a UV-Vis spectrophotometer. The in vitro cytotoxicity assay was performed using fibroblasts (L929 cell line). The MS/MS analyses were performed through direct infusion using a LCQ Fleet mass spectrometer equipped with APCI font and ion trap analyzer, in the positive and negative mode. A molecular network was created using the online workflow on the GNPS website (http://gnps.ucsd.edu). The phenolic content at 400μg was 25.24 ± 0.98μg.GAE/g, while the antioxidant activity showed an EC50 of 13.37±2.63 μg.mL-1. Dereplication led to the annotation of three flavonoids that may contribute to the observed antioxidant activity. The extract showed low cytotoxicity at the highest tested concentration (> 500μM). The results demonstrate that the extract from Ephedrantus amazonicus R.E. Fries leaves is a promising source of natural antioxidants. competition stress worldwide species Thus R E FolinCiocalteu Folin Ciocalteu methods respectively 96well well 96 microplates 63 51 nm UVVis UV Vis spectrophotometer L929 L (L92 line. line . line) MSMS MS analyzer mode http//gnps.ucsd.edu. httpgnpsucsdedu http //gnps.ucsd.edu gnps ucsd edu (http://gnps.ucsd.edu) μg 2524 25 24 25.2 098μgGAEg μgGAEg 0 98μg GAE g 0.98μg.GAE/g EC EC5 1337263 13 37 2 13.37±2.6 μg.mL1. μgmL1 μgmL μg.mL 1. mL 1 μg.mL-1 > ( 500μM. 500μM μM 500μM) RE R.E 9 6 5 L92 (L9 http//gnps.ucsd.edu gnpsucsdedu (http://gnps.ucsd.edu 252 25. 133726 3 13.37±2. mL1 μg.mL1 μg.mL- L9 (L 13372 13.37±2 1337 13.37± 133 13.37 13.3 13.

Aquaculture is one of the segments of the fastest growing animal production on the world stage. The survey of the phytoplankton community in these environments allows to establish more efficient forms of management. The objective of this research aimed to perform a qualitative analysis of phytoplankton aimed at understanding the aquatic ecological dynamics to support management measures for fish production. The study was conducted in Piscicultura Helena, km 14, TN 13, 4 GB, in the town of Alvorada d’Oeste, Rondônia, Brazil, where three acres of water depth are used to grow Colossoma macropomum. The dam supply and three ponds were chosen for analysis. The samples were collected bimonthly between August / 2013 to May / 2014. 74 taxa were identified. The class with the largest representation (23 taxa) and occurrence in nurseries (43%) was the Chlorophyceae, the dam where the supply is uncultivated Colossoma macropomum no monospecific dominance of the phytoplankton community. The cyanobacteria despite not having been the class of the greatest diversity of taxa proved influential in the phytoplankton community, with high densities of the genus Microcystis and Planktotrix which together with the genus Euglena (Euglenophyceae) caused occasional blooms in October / 2013 and February / 2014

A piscicultura é um dos segmentos da produção animal que mais cresce no cenário mundial. O levantamento da comunidade fitoplanctônica nestes ambientes permite estabelecer formas de manejo mais eficientes. Objetivou-se com esta pesquisa realizar a análise qualitativa da comunidade fitoplanctônica visando a compreensão da dinâmica ecológica aquática para subsidiar medidas de manejo para a produção piscícola. O estudo foi desenvolvido na Piscicultura Santa Helena, km 14, TN 13, GB 4, no município de Alvorada dâ´Oeste, Rondônia, Brasil, onde três hectares de lâmina d´água são destinados ao cultivo de Colossoma macropomum. A represa de abastecimento e três viveiros foram escolhidos para as análises. As coletas ocorreram bimestralmente entre agosto-2013 à maio-2014. Foram identificados 74 táxons. A classe com maior representatividade (23 táxons) e de ocorrência nos viveiros (43%) foi a Chlorophyceae, na represa de abastecimento onde não é cultivado Colossoma macropomum não houve dominância monoespecífica da comunidade fitoplanctônica. As Cianofíceas apesar de não terem sido a classe de maior diversidade de táxons se mostraram influentes na comunidade fitoplanctônica, com altas densidades do gênero Microcystis e Planktotrix que juntamente com o gênero Euglena (Euglenophyceae) ocasionaram florações pontuais em outubro-2013 e fevereiro-2014