148 research outputs found
Effect of drying temperature on the yield and phytochemical quality of the essential oil of pepper rosemary (Lippia origanoides Kunth) and of clove basil (Ocimum gratissimum L.) / Efeito da temperatura de secagem no rendimento e na qualidade fitoquímica do óleo essencial de alecrim-pimenta (Lippia origanoides Kunth) e de alfavaca (Ocimum gratissimum L.)
Among medicinal species, Lippia origanoides Kunth and Ocimum gratissimum L. stand out for its recognized therapeutic value associated with the medicinal properties of their essential oils. Drying is a critical point in post-harvest processing of medicinal plants for the conservation of bioactive compounds. This work aimed to evaluate the effect of drying temperature on the essential oil’s yield and phytochemical quality extracted from leaves of O. gratissimum and L. origanoides. The medicinal species were grown in an organic system and their leaves were harvest and immediately dried at 40, 50 and 60 °C. The essential oils were extracted from the leaves by hydrodistillation in Clevenger apparatus. There was detected a difference (P <0.01) in the essential oil yield of O. gratissimum with the increase in the drying temperature, being 1.35% (40 °C), 0.83% (50 °C) and 0.45% (60 °C) ). In L. origanoides there was detected a difference (P <0.01) in the essential oil yield only between 40 °C (3.4%) and 60 °C (2.84%). The increase of drying temperature reduced the levels of the major constituents of O. gratissimum (eugenol, germacrene D and caryophyllene oxide), but did not change the levels of the major constituents of L. origanoides (thymol, trans-caryophyllene and para-cymene). Considering that the increase of the drying temperature promote a reduction in the essential oil yield of both medicinal species and also in the major constituents concentration in O. gratisssimum, it is essential to select the correct drying temperature to guarantee the best yield and the phytochemical quality of the essential oil to ensure therapeutic efficacy. Here, we conclude that the best drying temperature to the essential oil’s yield and phytochemical quality is 40 °C for O. gratissimum and 40 or 50 °C for L. origanoides
Effect of drying temperature on yield and phytochemical quality of essential oil extracted from Mikania laevigata (Guaco) leaves / Efeito da temperatura de secagem sobre o rendimento e qualidade fitoquímica de óleo essencial extraído de folhas de Mikania laevigata (Guaco)
Mikania laevigata Sch. Bip. ex Baker, Asteraceae, commonly known as the guaco, is medicinal species native to Brazil. Among the critical points of post-harvest processing of medicinal species, the drying temperature must be considered, because its can interfere in the yield and phytochemical quality of plant material, and, consequently, in the therapeutic action. The effect of the drying temperature was evaluated on the yield and phytochemical quality of the essential oil extracted from M. laevigata leaves. The cultivation was carried out in an organic system and using the select genotype (Cenargen) for this region. The leaves were harvested and immediately submitted to drying process at 40, 50 and 60 °C. The essential oils were extracted by hydrodistillation in Clevenger apparatus and the chemical constituents was evaluated using gas chromatography coupled to the mass spectrophotometer (CG-MS). There was a reduction in the essential oil yield (p <0.05) with increasing drying temperature. However, at 60 ºC there was a higher concentration of coumarin to which the bronchodilator and expectorant action is attributed. Therefore, we recommended dry the M. laevigata leaves at 60 ºC to obtain the highest coumarin content and guarantee the bronchodilator and expectorant therapeutic effect
Morphological descriptors for the characterization of teak clones (Tectona grandis L.f.) in plantations
Aim of study: The objective of this work was to identify possible morphological descriptors for teak clones, in order to support the cultivars protection process of this species.Area of study: This experiment was carried out in ‘São José dos Quatro Marcos’, Mato Grosso, midwest Brazil.Material and methods: A teak clonal test, assessing 18 clones, was evaluated at the ages of 29 and 41 months by means of 41 morphological characteristics, related mainly to the branches, leaves and trunk. The clonal test was established in a randomized block design composed by three blocks, each block containing 18 plots, one for each clone. Each plot had 36 plants, but only the innermost five individuals were selected and evaluated. The information was organized in a presence and absence matrix. Subsequently, genetic similarity measures were estimated, by means of the Jaccard index, and a clustering was performed by the Unweighted Pair Group Method using the Arithmetic averages (UPGMA) method.Main results: A total of 26 and 28 morphological characteristic that exhibited DHS (distinction, homogeneity and stability) were identified at the ages of 29 and 41 months, respectively. Of these, 17 characteristics showed the same behavior at 29 and 41 months of age. However, it is important to emphasize that the evaluation must be performed under the same planting conditions in which these descriptors were developed.Research highlights: These 17 morphological characteristics can compose the list of potential morphological descriptors to be used in the process of teak clones/cultivars protection.Keywords: cultivars protection; morphological characteristics; distinction, homogeneity; stability
Política de estabilização de renda para a agricultura familiar: uma análise de risco.
Os produtores familiares foram prejudicados pelas políticas de substituição de importações e de modernização da agricultura, sofrendo com elevadas transferências de renda para fora do setor. Uma forma de ressarci-los seria implementando uma política de estabilização de renda que asseguraria rentabilidade estável aos produtores. O objetivo deste artigo é determinar os benefícios de uma política de estabilização de renda implementada na agricultura familiar para agricultores e consumidores de arroz, feijão, milho e mandioca, e os custos para agricultores comerciais nesses mercados. Utilizou-se o modelo de Newbery e Stiglitz, que considera a redução do risco com a política de estabilização de renda. A política implicaria aumento de receita para produtores familiares. Os benefícios de transferência superariam os de eficiência para produtores familiares e consumidores. Os benefícios para a agricultura familiar superariam os custos da agricultura comercial com a política nos mercados de feijão, mandioca e milho, e os benefícios totais superariam os custos totais nos mercados de feijão e milho, ao contrário ocorreria nos mercados de arroz e mandioca, embora neste fosse pequena a diferença. Conclui-se que a implementação da política seria viável nos mercados onde a participação da agricultura familiar fosse maior que a da comercial e naqueles importadores
Effect of drying temperature on the yield and phytochemical quality of the essential oil of mint (Mentha x villosa Huds.) / Efeito da temperatura de secagem no rendimento e na qualidade fitoquímica do óleo essencial de hortelã (Mentha x villosa Huds.)
A hortelã (Mentha x villosa Huds.) consta na Relação Nacional de Plantas Medicinais de Interesse ao SUS (RENISUS) devido ao reconhecimento de suas propriedades medicinais, dentre elas a atividade antiparasitária. Dentre as etapas do processamento pós-colheita de plantas medicinais, destaca-se a secagem como etapa crítica e essencial para a conservação dos compostos bioativos vegetais. Desta forma, objetivou-se avaliar o efeito da temperatura de secagem sobre o rendimento e a qualidade fitoquímica do óleo essencial extraído de folhas de hortelã. Realizou-se o cultivo em sistema orgânico em Oratórios, Minas Gerais, Brasil. Os ramos de hortelã foram colhidos e as folhas destacadas e submetidas à secagem em estufa de circulação forçada de ar a 40, 50 e 60 °C. A extração do óleo essencial foi feita por hidrodestilação em aparelho Clevenger, e para identificação dos constituintes químicos utilizou-se a cromatografia gasosa acoplada ao espectrofotômetro de massas (CG-MS). Constatou-se redução (P<0,001) do rendimento do óleo essencail com o aumento da temperatura de secagem das folhas. Não houve alteração do teor de óxido de piperitona (OP) (78 %), composto majoritário ao qual se atribui a atividade antiparasitária, nas temperaturas de secagem testadas. Entretato, observou-se maior diversidade de constituintes químicos identificados no óleo essencial obtido de folhas submetidas a secagem a 50 ºC. Os resultados contribuem para orientação de produtores no prcessamento pós-colheita das folhas de Mentha x villosa Huds visando a qualidade fitoquímica do óleo essencial e seu uso terapêutico como antiparasitário
Mechanism of firmness loss in guava cv. Pedro Sato during ripening at room temperature
O gênero Eustala (Araneae, Araneidae) no sul do Brasil: duas espécies novas, descrições complementares e novas ocorrências
The impact of SARS-CoV-2 in dementia across Latin America : A call for an urgent regional plan and coordinated response
The SARS-CoV-2 global pandemic will disproportionately impact countries with weak economies and vulnerable populations including people with dementia. Latin American and Caribbean countries (LACs) are burdened with unstable economic development, fragile health systems, massive economic disparities, and a high prevalence of dementia. Here, we underscore the selective impact of SARS-CoV-2 on dementia among LACs, the specific strain on health systems devoted to dementia, and the subsequent effect of increasing inequalities among those with dementia in the region. Implementation of best practices for mitigation and containment faces particularly steep challenges in LACs. Based upon our consideration of these issues, we urgently call for a coordinated action plan, including the development of inexpensive mass testing and multilevel regional coordination for dementia care and related actions. Brain health diplomacy should lead to a shared and escalated response across the region, coordinating leadership, and triangulation between governments and international multilateral networks
Human serum antibody reactivity towards Paracoccidioides brasiliensis antigens treated with sodium metaperiodate
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