9 research outputs found

    Avaliação preliminar da atividade antimicrobiana do extrato de erva-mate (Ilex paraguariensis A. St. - Hil.) obtido por extração com CO2 supercrítico

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    Ilex paraguariensis A. St. - Hil. (erva-mate) é uma árvore pertencente à família Aquifoleaceae, nativa da região sul da América do Sul e de grande importância cultural e econômica para os três estados da região sul do Brasil. O presente trabalho determinou o potencial antimicrobiano do extrato de erva-mate obtido por fluido supercrítico, frente a alguns microrganismos. As folhas de Ilex paraguariensis foram coletadas na região norte do RS. O extrato bruto da planta desidratada foi obtido pelo método de extração com fluido supercrítico, utilizando dióxido de carbono (CO2) como solvente. Foi obtida a solução mãe desse extrato (100 mg mL-1) que a seguir foi diluído (50; 25; 12,5; 6,25 mg mL-1) para avaliação da atividade antimicrobiana por meio da técnica de difusão do disco em ágar Müeller Hinton, sobre cepas de Acinetobacter baumannii (ATCC 19606), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923) e Enterococcus faecalis (ATCC 29212). As análises foram efetuadas em triplicata, utilizando como controle negativo disco estéril sem impregnação e como controle positivo discos de antibióticos comerciais variáveis de acordo com a espécie bacteriana. Após 16 a 24h de incubação a 35ºC os halos com significância foram medidos. Observou-se atividade antimicrobiana frente a S. aureus (halos de inibição variaram entre 7 e 18 mm) e para P. aeruginosa (halos entre 6 e 11 mm), ambos nas concentrações de 100 até 25 mg mL-1. O extrato obtido por extração em fluido supercrítico de Ilex paraguariensis apresentou atividade antimicrobiana frente a S. aureus e P. aeruginosa

    Analysis of volatile compounds of Ilex paraguariensis A. St. - Hil. and its main adulterating species Ilex theizans Mart. ex Reissek and Ilex dumosa Reissek Análise de compostos voláteis de Ilex paraguariensis A. St. - Hil. e suas principais espécies adulterantes Ilex theizans Mart. ex Reissek e Ilex dumosa Reissek

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    The adulteration of the product Ilex paraguariensis with other Ilex species is a mAjor problem for maté tea producers. In this work, three species of Ilex were evaluated for their volatile composition by headspace solid phase microextraction coupled to gas chromatography and mass spectrum detector (HS-SPME/GC-MS). The adulterating species I. dumnosa and I. theizans Mart. ex Reissek presented a different profile of volatile organic compounds when compared to I. paraguariensis. Aldehydes methyl-butanal, pentanal, hexanal, heptanal and nonanal were detected only in the adulterating species. This result suggests that such compounds are potential chemical markers for identification of adulteration and quality analysis of products based on Ilex paraguariensis.<br>A adulteração do produto Ilex paraguariensis com outras espécies de Ilex é um dos principais problemas dos produtores de erva-mate. Neste trabalho, três espécies de Ilex foram avaliadas quanto à sua composição volátil por microextração em fase sólida acoplada à cromatografia gasosa e detector de espectro de massas (HS-SPME/GC-MS). As espécies adulterantes I. dumnosa e I. theizans Mart. ex Reissek apresentaram um perfil diferente de compostos orgânicos voláteis, quando comparadas com a I. paraguariensis. Os aldeídos metil-butanal, pentanal, hexanal, heptanal e nonanal foram detectados apenas nas espécies adulterantes. Esse resultado sugere que esses compostos químicos são marcadores potenciais para a identificação de adulteração e análise da qualidade dos produtos à base de Ilex paraguariensis

    Extraction of carotenoids from Phaffia rhodozyma: A comparison between different techniques of cell disruption

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    The yeast Phaffia rhodozyma is known for producing carotenogenic pigments, commonly used in aquaculture feed formulation as well as in cosmetic, pharmaceutical, and food industries. Despite the high production of carotenoids from microorganisms by biotechnology, their use has limitation due to the cell wall resistance, which constitutes a barrier to the bioavailability of carotenoids. Therefore, there is a need to improve carotenoids recovering technique from microorganisms for the application of food industries. This study aimed to compare mechanical, chemical, and enzymatic techniques of cell disruption for extracting carotenoids produced by P. rhodozyma NRRL Y-17268. Among the techniques studied, the highest specific concentration of carotenoids (190.35 μg/g) resulted from the combined techniques of frozen biomass maceration using diatomaceous earth and enzymatic lysis at pH of the reaction medium of 4.5 at 55°C, with initial activity of β-1,3 glucanase of 0.6 U/mL for 30 min

    Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

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    International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora
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