19 research outputs found
Bioactivity of Licaria puchury-major essential oil against Aedes aegypti, Tetranychus urticae and Cerataphis lataniae
The present study was carried out to evaluate an alternative controlling agent for greenhouse pests and the yellow fever mosquito larvae. The potential bioactivity of Licaria puchury-major (Mart.) Kosterm. (âpuxuriâ) was evaluated here against three most common pests in tropical and subtropical countries: Aedes aegypti Linn. Larvae, Tetranychus urticae Koch. mites and Cerataphis lataniae Boisd. aphids. The essential oil from seeds was analyzed by GC-FID and GC-MS. The major compounds were safrole (38.8%) and eucalyptol (21.7%). Phenylpropanes (51.7%) was the main group of compounds and oxygenated monoterpenes represented 28.8% of the total oil. The essential oil has shown no inhibition of acetylcholinesterase (AChE) in the tested concentrations. However, potential antioxidant activities were evaluated by different methods [DPPH: LD50 = (27.8 ± 1.0) ”g/.mL; ABTS: (977.3 ± 25.2) ”M TEs/g (Trolox Equivalents); FRAP: (548.2 ± 29.0) ”M Fe(II)/g]. A significant larvicidal potential for 24 h of exposure was observed with LD50 = 98.9 ”g/mL, being an indicative that the larval mortality may occur by ingestion or contact due to the no inhibition against AChE. Volatile phase effects were evaluated against T. urticae Koch. and C. lataniae Boisd. and LD50 were found about 30.8 and 13.5 ”g/mL, respectively. These results are consistent with an octopaminergic effect, since some phenylpropanoids (such as Safrole, identified as the major compound in this work) can block octopamine, a multi-functional, naturally occurring biogenic amine. Then, this study clearly illustrated the efficacy of the investigated seeds, which encourages the development of a new potential natural controlling agent against these common pests due to the abundance of these seeds in the Amazon region and to the high essential oil yield. © 2018 ACG Publications. All rights reserved
Alternative Biodefensive based on the Essential Oil from Allium sativum Encapsulated in PCL/Gelatin Nanoparticles
The goal of this paper was to develop a biodegradable system containing the essential oil from Allium sativum bulbs encapsulated in PCL/gelatin-based nanoparticles, as well as evaluate its efficiency to control Aedes aegypti Linn. larvae and Cerataphis lataniae Bois. aphids. The essential oil was analyzed by GC-FID and GC-MS, and six compounds were identified, representing 93.1% of the total oil. The major compounds were diallyl trisulfide (51.8%), diallyl disulfide (23.2%) and allyl methyl trisulfide (13.6%). The PCL/gelatin-based nanoparticles containing this essential oil exhibited encapsulation efficiency higher than 94%, average particle diameter around 200 nm and zeta potential values about -36 mV. The essential oil presented no antioxidant nor enzymatic activities, so its effectiveness might be explained by the presence of sulfur compounds. The release kinetics of the encapsulated essential oil confirmed the release mechanism by the Fick's Law. About 50% of the encapsulated essential oil was released after 1 h, and about 90% was released after 50 h. This behavior is interesting from the technological point of view since the nanoparticles released as much oil as possible in a short period of time and then the lethal dosages were maintained along the time. Nanoparticles containing the encapsulated essential oil was submitted to in vitro bioassays against A. aegypti and C. lataniae and showed 100% of mortality against larvae and aphids up to 24 h. In conclusion, the essential oil from A. sativum presented effectiveness to be applied in sustainable management of pests in greenhouses, as well as for larvicidal control
Efeito do tratamento térmico na concentração de carotenóides, compostos fenólicos, åcido ascórbico e capacidade antioxidante do suco de tangerina murcote
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,5â7 vast areas of the tropics remain understudied.8â11 In
the American tropics, Amazonia stands out as the worldâs 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.13â15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazonâs 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 regionâs vulnerability to environmental change. 15%â18% 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
A História da Alimentação: balizas historiogråficas
Os M. pretenderam traçar um quadro da HistĂłria da Alimentação, nĂŁo como um novo ramo epistemolĂłgico da disciplina, mas como um campo em desenvolvimento de prĂĄticas e atividades especializadas, incluindo pesquisa, formação, publicaçÔes, associaçÔes, encontros acadĂȘmicos, etc. Um breve relato das condiçÔes em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biolĂłgica, a econĂŽmica, a social, a cultural e a filosĂłfica!, assim como da identificação das contribuiçÔes mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histĂłrica, foi ela organizada segundo critĂ©rios morfolĂłgicos. A seguir, alguns tĂłpicos importantes mereceram tratamento Ă parte: a fome, o alimento e o domĂnio religioso, as descobertas europĂ©ias e a difusĂŁo mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rĂĄpido balanço crĂtico da historiografia brasileira sobre o tema
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%â18% 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
Bioactivity of Licaria puchury-major Essential Oil Against Aedes aegypti , Tetranychus urticae and Cerataphis lataniae
The present study was carried out to evaluate an alternative controlling agent for greenhouse pests and the yellow fever mosquito larvae. The potential bioactivity of Licaria puchury-major (Mart.) Kosterm. (âpuxuriâ) was evaluated here against three most common pests in tropical and subtropical countries: Aedes aegypti Linn. Larvae, Tetranychus urticae Koch. mites and Cerataphis lataniae Boisd. aphids. The essential oil from seeds was analyzed by GC-FID and GC-MS. The major compounds were safrole (38.8%) and eucalyptol (21.7%). Phenylpropanes (51.7%) was the main group of compounds and oxygenated monoterpenes represented 28.8% of the total oil. The essential oil has shown no inhibition of acetylcholinesterase (AChE) in the tested concentrations. However, potential antioxidant activities were evaluated by different methods [DPPH: LD 50 = (27.8 ± 1.0) ”g/.mL; ABTS: (977.3 ± 25.2) ”M TEs/g (Trolox Equivalents); FRAP: (548.2 ± 29.0) ”M Fe(II)/g]. A significant larvicidal potential for 24 h of exposure was observed with LD 50 = 98.9 ”g/mL, being an indicative that the larval mortality may occur by ingestion or contact due to the no inhibition against AChE. Volatile phase effects were evaluated against T. urticae Koch. and C. lataniae Boisd. and LD 50 were found about 30.8 and 13.5 ”g/mL , respectively. These results are consistent with an octopaminergic effect , since some phenylpropanoids (such as Safrole, identified as the major compound in this work) can block octopamine, a multi-functional, naturally occurring biogenic amine. Then, this study clearly illustrated the efficacy of the investigated seeds, which encourages the development of a new potential natural controlling agent against these common pests due to the abundance of these seeds in the Amazon region and to the high essential oil yield
A Sociedade de Medicina e Cirurgia do Rio de Janeiro: a gĂȘnese de uma rede institucional alternativa The Rio de Janeiro Medical and Surgical Society: the genesis of an alternative institutional network
Este artigo aborda a histĂłria da medicina no Brasil no final do sĂ©culo XIX, a partir da anĂĄlise do surgimento da Sociedade de Medicina e Cirurgia do Rio de Janeiro. Nossa hipĂłtese Ă© de que, a partir da dĂ©cada de 1880, a reformulação das instituiçÔes e a diversificação da coletividade mĂ©dica iniciaram a estruturação de um campo de relaçÔes sociais especĂficas aos praticantes da medicina. Diante da crise das instituiçÔes mĂ©dicas oficiais, verifica-se o surgimento de grupos mĂ©dicos alternativos que, Ă margem da tutela estatal, se articularam em torno cie objetivos comuns, em especial, a construção de um conhecimento mĂ©dico nacional, que tivesse relevĂąncia no cenĂĄrio cientĂfico internacional da Ă©poca.<br>Creation of the Rio de Janeiro Medical and Surgical Society serves as the basis for this study of late-19th-century medicine in Brazil. The hypothesis is that beginning in the 1880s changes to institutions and the diversification of the medical community inaugurated the structuring of afield of social relations specific to medical practitioners. With official medical institutions undergoing crises, alternative groups that emerged outside the government framework worked together toward common ends, particularly the construction of a kind of Brazilian medical knowledge that could play a role on the international scientific scenario