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Bioactive extracts of red seaweeds Pterocladiella capillacea and Osmundaria obtusiloba(Floridophyceae:Rhodophyta) with antioxidant and bacterial agglutination potential

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Asian Pacific Journal of Tropical Medicine 2016年第4期9卷 363-370页

作者： Daniel Barroso de Alencar Fátima Cristiane Teles de Carvalho Rosa Helena Rebouas Daniel Rodrigues dos Santos Kelma Maria dos Santos Pires-Cavalcante Rebeca Larangeira de Lima Bárbara Mendes Baracho Rayssa Mendes Bezerra Francisco Arnaldo Viana Regine Helena Silva dos Fernandes Vieira Alexandre Holanda Sampaio Oscarina Viana de Sousa Silvana Saker-Sampaio laboratrio de Produtos Naturais Marinhos.departamento de Engenharia de Pesca Universidade Federal do Ceará.Campus do Pici.Ar.Mister Hull.s/nCaixa Postal 6043 laboratrio de Microbiologia Ambiental e do Pescado.Instituto de Ciências do Mar.Universidade Federal do Ceará.Av.da Abolicao 3207 laboratrio de Microbiologia Ambiental e do Pescado.Instituto de Ciências do Mar.Universidade Federal do Ceará laboratrio de Produtos Naturais Marinhos.departamento de Engenharia de Pesca Universidade Federal do Ceará laboratrio de cromatografia Departamento de QuimicaUniversidade do Estado do Rio Grande do NorteCampus Universitário Central

Objective:To evaluate the antioxidant,antibacterial and bacterial cell agglutination activities of the hexane(Hex) and 70%ethanol(70%EtOH) extracts of two species of red seaweeds Pterocladiella capillacea(***) and Osmundaria ***:In vitro antioxidant activity was determined by DPPH radical scavenging assay,ferric-reducing antioxidant power assay,ferrous ion chelating assay,β-carotene bleaching assay and total phenolic content *** activity was tested using the method of disc diffusion on Mueller-Hinton *** ability of algal extracts to agglutinate bacterial cells was also ***:The 70%EtOH extract of the two algae showed the highest values of total phenolic content compared to the Hex *** results of DPPH for both extracts(Hex,70%EtOH) of Osmundaria obtusiloba(43.46%and 99.47%) were higher than those of ***(33.04%and 40.81%) at a concentration of 1 000 μg/*** for the ferrous ion chelating,there was an opposite behavior,extracts of *** had a higher *** extracts showed a low ferric-reducing antioxidant power,with optical density ranging from0.054 to *** activities of all extracts evaluated for β-carotene bleaching were above 40%.There was no antibacterial activity against bacterial strains ***,the extracts of both species were able to agglutinate bacterial Gram positive cells of Staphylococcus aureus and Gram negative cells of Escherichia coli,multidrug-resistant Salmonella and Vibrio *** This is the first report of the interaction between these algal extracts,rich in natural compounds with antioxidant potential,and Gram positive and Gram negative bacterial cells.

关键词： Bioactive compounds Antioxidant Bacterial agglutination Rhodophyta

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Fraud investigation in commercial coffee by chromatography

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Food Quality and Safety 2018年第3期2卷 121-133页

作者： Víctor de Carvalho Martins Ronoel Luiz de Oliveira Godoy Ana Cristina Miranda Senna Gouvêa Manuela Cristina Pessanha de Araujo Santiago Renata Galhardo Borguini Elaine Cristina de Oliveira Braga Sidney Pacheco Luzimar da Silva de Mattos do Nascimento departamento de Tecnologia de Alimentos Instituto de TecnologiaUniversidade Federal Rural do Rio de JaneiroCEP 23890-000Seropédica-RJBrazil laboratório de cromatografia Líquida Embrapa Agroindústria de AlimentosCEP 23020-470Rio de Janeiro-RJBrazil Centro de Tecnologia Instituto de QuímicaUniversidade Federal do Rio de JaneiroCEP 22290-180Rio de Janeiro-RJBrazil

Coffee is currently the second largest commodity on the world market today,and there is great concern about the quality of the beans exported from producer countries to Europe and *** such as using blends of different species and adding low-cost raw materials,such as chicory,corn,and soybean,impair the sensory and functional characteristics of the drink made from roasted and ground coffee *** is a need to adopt more efficient analytical methods than the microscopy technique currently *** first chromatographic method used to determine fraud was reported in *** method used paper chromatography to differentiate between coffee and chicory based on the free reducing *** of the 1980s,different methods involving high-performance liquid chromatography and gas chromatography were developed in order to demonstrate geographic authenticity,distinction between species,occurrence of adulteration,and the presence of defective beans by determining the monosaccharides,oligosaccharides,tocopherols,fatty acids,volatiles,diterpenes,sterols,and phenolic substances,among *** far as the authors know,there are no papers published in the literature that have compiled such an extensive set of information about these chromatographic methods as *** the last 2 years,there has been a trend to develop analytical methods for ultra-performance liquid chromatography coupled with tandem mass spectrometry to confirm fraud in coffee,due to high sensitivity and selectivity.

关键词： adulteration coffee chromatographic methods carbohydrates volatile substances

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Gross Chemical Profile and Calculation of Nitrogen-to-Protein Conversion Factors for Five Tropical Seaweeds

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American Journal of Plant Sciences 2011年第3期2卷 287-296页

作者： Graciela S.Diniz Elisabete Barbarino João Oiano-Neto Sidney Pacheco Sergio O.Lourenco departamento de Biologia Marinha Universidade Federal FluminenseNiteróiBrazil laboratório de cromatografia Líquida Embrapa Agroindústria de AlimentosRio de JaneiroBrazil Instituto Virtual Internacional de Mudanças Globais Universidade Federal do Rio de Janeiro—UFRJ/IVIGRio de JaneiroBrazil

despite decades of research on marine algae, there are still significant gaps in basic knowledge about chemical composition of these organisms, especially in tropical environments. In this study, the amino acid composition and contents of total nitrogen, phosphorus, lipid, carbohydrate and protein were determined in Asparagopsis taxiformis, Centroceras clavulatum, Chaetomorpha aerea, Sargassum filipendula and Spyridia hypnoides. The seaweeds showed low lipid contents (lower than 5.5% d.w. in all species) and were rich in carbohydrates (more than 16% d.w. in all seaweeds). The percentage of nitrogen, phosphorus and protein varied widely among species, which red algae showed the highest con-centrations. The amino acid composition was similar among the seaweeds, which glutamic acid, aspartic acid and leu-cine as the most abundant. All species are poor in histidine. An average of 24.2% of the total nitrogen is non-proteinaceous. From data of total amino acid and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-to-protein conversion factors calculated ranged from 4.51 to 5.21, with an overall average of 4.86. These findings show that the traditional conversion factor of 6.25 should be avoided for seaweeds, since it overestimates the actual protein content.

关键词： Nitrogen-to-Protein Conversion Factors Protein Amino Acid Seaweeds Element Composition Tropical Environment

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Acaricidal activity of derris floribunda essential oil and its main constituent

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Asian Pacific Journal of Tropical Biomedicine 2017年第9期7卷 791-796页

作者： Ana Claudia Fernandes Amaral Aline de SRamos Marcia Reis Pena Jose Luiz Pinto Ferreira Jean Michel SMenezes Geraldo JNVasconcelos Neliton Marques da Silva Jefferson Rocha de Andrade Silva Lab de Plantas Medicinais e derivados Depto de Quimica de Produtos NaturaisFarmanguinhosFundacao Oswaldo CruzRio de JaneiroRJBrazil Lab de Entomologia e Acarologia Agricola Faculdade de Ciencias AgrariasUniversidade Federal do AmazonasManausAMBrazil Lab de cromatografia Depto de QuímicaUniversidade Federal do AmazonasManausAMBrazil 4Instituto de Ciencias Exatas e TecnologiaUniversidade Federal do AmazonasItacoatiaraAMBrazil

Objective: To evaluate the acaricidal activity of the essential oil obtained from roots of derris floribunda(D. floribunda)(Miq.) Benth, and its main constituent nerolidol against the Mexican mite Tetranychus mexicanus(T. mexicanus)(Mc Gregor).Methods: The essential oil from the roots of D. floribunda collected in the Amazon region(Brazil) was obtained by hydrodistillation. Its chemical composition was determined by GC–MS analysis. The acaricidal activities of this essential oil and nerolidol,were evaluated by recording the number of dead females(mortality) and eggs(fertility).Results: The essential oil showed sesquiterpenes as major volatile components. Nerolidol, the main component, represented 68.5% of the total composition of the essential oil. D. floribunda essential oil and nerolidol showed acaricidal activity, with LC_(50) of9.61 mg/m L air and 9.2 mg/m L air, respectively, over a 72 h period. In addition, both the essential oil and nerolidol significantly reduced the fecundity of T. ***: Due to the economic importance of T. mexicanus and the lack of new pesticides, our data are very promising in the search for efficient and safer acaricidal products. Furthermore, this is the first report about the chemical composition and bioactivity of the essential oil of the Amazon plant species D. floribunda.

关键词： Acaricidal activity Essential oil Nerolidol Organic agriculture Sesquiterpenes Timb

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Sensory neurons in the spinal cord of nominal female embryos in the marine turtle Lepidochelys olivacea respond to shifts in incubation temperature:implications for temperature dependent sex determination

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Advances in Bioscience and Biotechnology 2011年第1期2卷 1-7页

作者： Francisco Jimenez-Trejo Leonora Olivos-Cisneros Julieta Mendoza-Torreblanca Sofia Diaz-Cintra Esperanza-Melendez-Herrera Armida Baez-Saldana Patricia Padilla Cortes Gabriel Gutierrez-Ospina Alma Lilia Fuentes-Farias departamento de Biologia Facultad de QuimicaUniversidad Nacional Autonoma de MexicoMexico D.F.Mexico 04510 departamento de Biologia Celular y Fisiologia Instituto de Investigaciones BiomedicasUniversidad Nacional Autonoma de MexicoMexico D.F.Mexico 04510 departamento de Neuroquimica Instituto Nacional de PediatriaMexicoDF.Mexico 04530 departamento de Neurobiologia del desarrollo y Neurofisiologia Instituto de NeurobiologiaUniversidad Nacional Autonoma de MexicoCampus UNAM-JuriquillaJuriquillaQueretaro Mexico AP.1-1141 laboratorio de Invertebrados y Ecofisiologia Animal Facultad de BiologiaUniversidad Michoacana de San Nicolas de HidalgoMoreliaMichoacanMexico 58040 Unidad de cromatografia Liquida de Alta Resolucion Instituto de Investigaciones BiomedicasUniversidad Nacional Autonoma de MexicoMexico D.F.Mexico 04510

Gonadal determination in marine turtles depends on incubation temperature. The mechanisms that spark off this process remain unclear. Previously, we proposed that sensory nerves reaching the gonadal primordium in nominal female embryos of Lepidochelys (L) olivacea may sense and signal incubation temperature. These nerves could later trigger ovarian determination by releasing neurotransmitters in a code constructed based on the thermal information (Gutierrez-Ospina et al., Acetylcholinesterase-positive innervation is present at the undifferentiated stages of the sea turtle Lepidochelys olivacea embryo gonads: implications for temperature-dependent sex determination, J. Comp. Neurol. 410 (1999) 90-98). The hypothesis briefly described, however, has been recently refuted under weak theoretical grounds and experimental misinterpretations (see introduction). Here, we present preliminary results that show that nominal female embryos have sensory neurons located in the dorsal horn laminae I and II of the lumbar spinal cord that display increased c-Fos-like immuno-staining after being incubated either at 15°C or 50°C. Because these spinal neurons are the primary central target of dorsal root ganglion neurons that innervate the urogential crest, these observations keep open the possibility that gonadal sensory nerves indeed signal thermal information that could later be used to trigger or instruct ovarian specification in marine turtles.

关键词： Reptiles Ovarian determination c-Fos Incubation Temperature Sensory Neurons

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