DETERMINAÇÃO DA CONCENTRAÇÃO DE POLIFENÓIS E DO POTENCIAL

Dicksonia sellowiana, a tipical plant from Atlantic Forest, is popularly known by xaxim or samambaiacu. The xaxim is used to make supports for ornamental plants; as well as is used against scabies, itch in the body and solitaria by the indians, and popularly is used as fibre source. Studies have shown medical value in the breath system. Knowing the increasing search for phytoterapics with antioxidant action against free radicals, the objective of this study was to evaluate the potencial antioxidant of the hexane, the diclorometane and the ethyl acetate fractions, as well as of the total extract of Dicksonia sellowiana leaves, and to verify the phenolic compounds concentration of these fractions. The Folin-Ciocalteau method was used to determine the phenolic acids doses, using acid galic as a phenolic compound standard. The antioxidant activity was determined by the phosphomolybdenum complex reduction, using vitamin C and rutin as antioxidants standards. The increasing values of phenolic acids concentration and of antioxidant activity are: hexane fraction, total extract, diclorometane fraction and ethyl acetate fraction. These results showed that the phenolic compounds of xaxim had significant contribution to the antioxidant activity, and, regarding that these compounds have the higher concentration in the ethyl acetate fraction, this fraction has the more significant antioxidant activity, which can be studied for the action against the free radicals. Key words: Dicksonia sellowiana, phenolic acids, antioxidant activity.A Dicksonia sellowiana, planta típica da Mata Atlântica, é popularmente conhecida como xaxim ou samambaiaçú. O xaxim é utilizado para a fabricação de suportes para plantas ornamentais; também usado contra sarna, coceira no corpo e solitária pelos índios , e popularmente como fonte de fibras. Estudos revelam seu valor medicinal no sistema respiratório. Conhecendo-se a crescente busca por fitoterápicos com antioxidantes que combatem radicais livres, o presente trabalho teve como objetivo analisar o potencial antioxidante das frações hexano, diclorometano e acetato de etila e do extrato total de folhas de Dicksonia sellowiana, e verificar a concentração de polifenóis das mesmas. O doseamento de compostos fenólicos foi realizado pelo método de Folin-Ciocalteau, usando-se ácido gálico como padrão de composto fenólico. A atividade antioxidante foi determinada pelo ensaio de redução do complexo fosfomolibdênio, usando-se vitamina C e rutina como padrões de antioxidantes. A partir dos ensaios pode-se observar que tanto os valores de concentração de compostos fenólicos como os de atividade antioxidante são decrescentes na ordem: fração acetato de etila, fração diclorometano, extrato total e fração hexano. Este resultado demonstra que os polifenóis do xaxim contribuem significativamente para a atividade antioxidante, e, pelo fato destes estarem presentes em maior concentração na fração acetato de etila, esta apresenta o potencial antioxidante mais significativo, o qual pode vir a ser estudado no combate à radicais livres. Palavras-chaves: Dicksonia sellowiana, compostos fenólicos, atividade antioxidante

ATENÇÃO FARMACÊUTICA NA ANTIBIOTICOTERAPIA

A escolha correta do antimicrobiano requer diagnóstico clínico laboratorial (identificação do agente infeccioso e antibiograma) e conhecimento farmacológico das drogas utilizadas na terapêutica. Os antibióticos são dispensados livremente nas farmácias sem necessidade de prescrição médica, favorecendo a aparecimento de problemas como terapia ineficaz, resistência bacteriana e indução da auto medicação, uma vez que balconistas recebem comissão na venda de medicamentos. O atendimento requer a atenção farmacêutica onde se possa realizar a anamnese do paciente, estabelecendo-se um sistema seguro, efetivo e que beneficia a farmacoterapia com o objetivo de obter resultados terapêuticos definidos na saúde e qualidade de vida do paciente. PHARMACEUTICAL ASSISTANCE IN ANTIBIOTICS THERAPY Abstract The correct choice of an antimicrobial therapy requires clinical and laboratorial diagnosis (identification of infectious agent and antibiogram) and pharmacological knowledge of drugs used in therapeutics. Antibiotics are freely dispensed in drugstores with no need of medical prescription, leading to the appearance of problems such as inefficient therapy, bacterial resistance and induction of selfmedication, once sellers receive commission on sales of medicine. The correct selling requires the pharmaceutical care, when its possible to collect information from the patient, establishing a safe and effective system that benefits the pharmacotherapy in order to reach defined therapeutic results on health and quality of life of patient

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost