Potencial larvicida de extratos de plantas regionais no controle de larvas de Aedes aegypti

Dengue, amongst the virus illnesses one can get by vectorial transmission, is the one that causes more impact in the morbidity and mortality of world s population. The resistance to the insecticides has caused difficulties to control of vector insect (Aedes aegypti) and has stimulated a search for vegetables with larvicidal activity. The biodiversity of Caatinga is barely known and it is potential of use even less. Some plants of this biome are commercialized in free fairs northeast of Brazil, because of its phytotherapics properties. The vegetables in this study had been selected by means of a questionnaire applied between grass salesmen and natives of the Serido region from Rio Grande do Norte state; culicids eggs had been acquired with traps and placed in container with water for the larva birth. Thirty larvae had been used in each group (a group control and five experimental groups), with four repetitions four times. The vegetables had been submitted to the processes of decoction, infusion and maceration in the standard concentration of 100g of the vegetable of study in 1l of H2O and analyzed after ½, 1, 2, 4, 8, 12, 24 and 48 hours for verification of the average lethal dose (LD50) from the groups with thirty larva. The LD50 was analyzed in different concentrations (50g/l, 100g/l, 150g/l, 200g/l e 300g/l) of Aspidosperma pyrifolium Mart. 48 extracts of rind, leaf and stem of the seven vegetal species: Aspidosperma pyrifolium Mart., Mimosa verrucosa Benth, Mimosa hostilis (Mart.) Benth., Myracrodruon urundeuva Allemão, Ximenia americana L, Bumelia sartorum Mart Zizyphus joazeiro Mart, had been analyzed. The extracts proceeding from the three methods were submitted to the freezedrying, to evaluate and to quantify substances extracted in each process. The results had shown that Aspidosperma pyrifolium Mart. and Myracrodruon urundeuva Allemão are the species that are more distinguished as larvicidal after 24 hours of experiment, in all used processes of extraction in the assays. The Zizyphus joazeiro Mart species has not shown larvicidal activity in none of the assays. In relation to the extraction method, the decoction was the most efficient method in the mortality tax of the A. aegypti larvae

Avaliação da atividade antimalárica e citotóxica de plantas medicinais dos Biomas Caatinga e Amazônico

Resistance of Plasmodium falciparum to the usual antimalarials, as well as their adverse effects and high cost, has led to the search of new drugs against malaria. Several of these have been developed from medicinal plants based on ethnopharmacology, including the most widely used antimalarials today: quinine and artemisinin. In the present study schizonticide activity of extracts and fractions of a number of medicinal plants from the Caatinga and Amazon biomes were assessed based on ethnopharmacological and chemosystematic information. These included Ximenia americana, Maytenus rigida, Sideroxylon obtusifolium, Stryphnodendro coriaceum, Bowdichia virgiliodes, Schinopis brasiliensis and Picrolemma sprucei, the last, an Amazon species. Antimalarial tests of blood schizonticides were conducted in Swiss mice infected with P. berghei and in vitro against P. falciparum. In vitro cytotoxicity studies were carried out using HeLa, CHO, 3T3, Raw and HEPG2 cell lines. Except for X. americana, all species exhibited in vivo or in vitro antimalarial activity, inhibiting parasitic growth by up to 79%. Extracts exhibited moderate toxicity with dosedependent kinetics. In this sense, ethnopharmacological and chemosystematic approaches were shown to be useful and promising tools in the search of new drugs. These findings represent a significant contribution to scientific knowledge of the antimalarial potential of Brazilian flora, thereby opening perspectives for the development of new antimalarials

Atividade antiplasmódica e toxicológica de plantas medicinais usadas popularmente no Brasil : uma abordagem etnobotânica

Malaria is a disease of global distribution, recognized by governments around the world as a serious public health problem, affecting more than 109 countries and territories and endangering more than 3.3 billion people. The economic costs of this disease are also relevant: the African continent itself has malaria-related costs of about $ 12 billion annually. Nowadays, in addition to chloroquine, Plasmodium falciparum is resistant to many drugs used in the treatment of malaria, such as amodiaquine, mefloquine, quinine and sulfadoxine-pyrimethamine; resistance of Plasmodium vivax to treatments, although less studied, is also reported. Nature, in general, is responsible for the production of most known organic substances, and the plant kingdom is responsible for the most of the chemical diversity known and reported in the literature. Most medicinal plants commercialized in Brazil, however, are of exotic origin, which makes the search for endemic medicinal plants, besides a patent necessity, a fascinating subject of academic research and development. This study aimed to: (i) verify the antimalarial activity of ethanolic and hydroalcoholic extracts of Boerhavia paniculata Rich. And acetonic extract of Clethra scabra Pers. in Swiss albino mice infected by Plasmodium berghei NK65, (ii) observe possible combined effects between the course of infection by P. berghei NK65 and administration of these extracts in Swiss albino mice, and (iii) conduct a preliminary study of the acute toxicity of these extracts in Swiss albino mice. All extracts notable pharmacological activities - with parasite infections inhibitions ranging from 22% to 54%.These characteristics suggest that the activities are relevant, although comparatively lower than the activity displayed by the positive control group (always above 90%). The general framework of survival analysis demonstrates an overall reduction in survival times for all groups. Necroscopy has not pointed no change in color, shape, size and/or consistency in the evaluated organs - the only exception was the livers of rats submitted to treatment to hydroalcoholic extracts: these organs have been presented in a slightly congestive aspect with mass increasing roughly 28% higher than the other two groups and a p-value of 0.0365. The 250 mg/Kg ethanolic group has been pointed out by the Dunn s post test, as the only class with simultaneous inequalities (p<0.05) between positive and negative control groups. The extracts, notably ethanol extract, have, in fact, a vestigial antimalarial activity, although well below from the ones perceived to chloroquine-treated groups; nevertheless, the survival times of the animals fed with the extracts do not rise by presence of such therapy. Both the toxicopharmacological studies of the synergism between the clinical course of malaria and administration of extracts and the isolated evaluation of toxicity allow us to affirm the absence of toxicity of the extracts at the level of CNS and ANS, as well as their non-influence on food and water consumption patterns, until dosages of 500 mg/Kg. Necroscopic analysis leads us to deduct a possible hepatotoxic effect of hydroalcoholic extract at dosages of 500 mg/Kg, and an innocuous tissue activity of the ethanol extract, in the same dosage. We propose a continuation of the studies of these extracts, with protocol modifications capable of addressing more clearly and objectively their pharmacological and toxicological aspects

Atividade antibacteriana das plantas copaifera duckei dwyer e pseudobombax marginatum e sua interação com a superfície celular bacteriana

A resistência microbiana a antimicrobianos tem favorecido a busca por substâncias bioativas provenientes de plantas usadas na medicina popular, com o intuito de se obter novos fármacos com atividade antimicrobiana. Neste estudo, foi proposta a investigação da atividade antibacteriana do óleo-resina de Copaifera duckei e de diferentes extratos da casca de Pseudobombax marginatum, e seus possíveis mecanismos de ação. O potencial inibitório antibacteriano foi avaliado utilizando-se os métodos de difusão e diluição em ágar, e a bioautografia. O mecanismo de ação foi analisado por microscopia eletrônica, no qual se observou alterações na ultraestrutura bacteriana, e por eletroforese em SDS-PAGE, que determinou ação sobre as proteínas das superfícies celulares. A análise química foi realizada pelas técnicas de Espectrometria de massas acoplada ao Cromatógrafo a gás- EM/CG (C. duckei) e Cromatografia Líquida de Alta Eficiência- CLAE (P. marginatum). Entre as bactérias estudadas, B. cereus foi a mais suscetível às plantas em estudo, com concentrações inibitórias mínimas (CIMs) correspondentes a 0,3125 mg/mL para o óleo-resina de copaíba, e 0,5 mg/mL para extrato hidroalcoólico (1:1) e 0,512 mg/mL para a fração butanólica da casca P. marginatum, nos quais pôde-se observar alterações na parede celular do B. cereus, com remoção da camada S, espessamento da parede celular e formação de diversos septos nos centros de divisão celular. A análise química por EM/CG mostrou compostos terpênicos no óleo-resina de C. duckei, tendo como composto majoritário o β-bisaboleno, e a análise por CLAE mostrou a presença de compostos derivados da catequina na casca do P. marginatum. Desta forma, as plantas em estudo mostram um potencial antibacteriano considerável, podendo contribuir tanto na terapia antimicrobiana como na área de alimentos, tendo como um de seus prováveis sítios de ação a parede celular bacteriana

Mestres e aprendiz: perambulando por ilhas de resistência

Monoculture of mind This idea, presented by Vandana Shiva, reflects the phase that we have experienced in the world: a notion of civilization that, since many decades, characterized by a technocratic big trend, has been shown as dominant and hegemonic. Based on a thinking and acting, felling and whishing standardization, this wave ends implying in what can be called of humanity‟s crisis at civilizational process. Destruction of simpler and more harmonious lifestyles with nature, human relations increasingly distant, values embrittlement, as respect, goodness and love, are some consequences of that behavioral homogenization. In the other hand, appears an archipelago of cultural and cognitive resistance against this devastating wave. Edgar Morin and Ceiça Almeida refer to this archipelago as a South Thought , what is not just a geographic question. Report, therefore, to some places, peoples, island that keep ancient costumes and knowledge, orally transmitted, for instance, from elders to younger, or vice versa, in an almost constant flow. Particular ways of experiencing the world around themselves, the men, animals, plants, rocks, or even not alive beings, masters or enchanted, spiritual guides. Next to a logic of sensitive, as Claude Levi-Strauss proposes, this reading, which is a more attentive, observer and wiser posture of surroundings, is based on touching, smelling, eating, seeing, and, I would add, felling. In light of this, I try to expatiate about certain experiences that I had the pleasure of living in some of these islands of resistance. Talks, perceptions, observations, sensations Stories, prose, poetries, music, photos, graphics Whatever could serve to portray even a bit of the reflections and forms to understand (ourselves) and produce knowledge, such as from a formation/Education to life, was well used at this ethnographic work. Space to the subjectivity and emotions I had, have, and will have a lot Everything for the dear reader may fell traveling around the world of tradition, resistance

Estudo e implementação em plantas físicas de um controlador preditivo generalizado com restrições

This work shows a study about the Generalized Predictive Controllers with Restrictions and their implementation in physical plants. Three types of restrictions will be discussed: restrictions in the variation rate of the signal control, restrictions in the amplitude of the signal control and restrictions in the amplitude of the Out signal (plant response). At the predictive control, the control law is obtained by the minimization of an objective function. To consider the restrictions, this minimization of the objective function is done by the use of a method to solve optimizing problems with restrictions. The chosen method was the Rosen Algorithm (based on the Gradient-projection). The physical plants in this study are two didactical systems of water level control. The first order one (a simple tank) and another of second order, which is formed by two tanks connected in cascade. The codes are implemented in C++ language and the communication with the system to be done through using a data acquisition panel offered by the system producer

Atividades biológicas de extratos salinos de sementes de plantas da caatinga contra Aedes Aegypti e investigação da participação de proteínas bioativas

Dengue fever, currently the most important arbovirus, is transmitted by the bite of the Aedes aegypti mosquito. Given the absence of a prophylactic vaccine, the disease can only be controlled by combating the vector insect. However, increasing reports of resistance and environmental damage caused by insecticides have led to the urgent search for new safer alternatives. Twenty - um plant s eed extracts from the Caatinga were prepared , tested and characterized . Sodium phosphate ( 50 mM pH 8.0) was used as extractor. All extracts showed larvicidal and ovipositional deterrence activity . Extracts of D. grandiflora, E. contortisiliquum, A. cearenses , C. ferrea and C. retusa were able to attract females for posture when in low co ncentration . In the attractive concentrations, the CE of E. contortisiliquum and A. cearenses were able to kill 52% and 100% of the larvae respectively . The extracts of A. cearenses , P. viridiflora, E. velutina, M. urundeuva and S. brasiliensis were also pupicides, while extracts of P. viridiflora, E. velutina, E. contortisiliquum , A. cearenses, A. colubrina, D. grandiflora , B. cheilantha , S. spectabilis, C. pyramidalis, M. regnelli e G. americana displayed adulticidal activity. All extracts were toxic to C. dubia zooplankton . The EB of E. velutina and E. contortisiliquum did not affect the viability of fibroblasts . In all extracts were identified at least two potential insecticidal proteins such as enzyme inhibitors, lectins and chitin - binding proteins and components of secondary metabolism . Considering all bioassays , the extracts from A. cearenses, P. viridiflora, E. contortisiliquum , S. brasiliensis, E. velutina and M. urundeuva were considered the most promising . The E. contortisiliquum extracts was the only one who did not show pupicida activity, indicating that its mechanism of action larvicide and adulticidal is related only to the ingesti on of toxic compounds by insect , so it was selected to be fragmenting. As observed for the CE , th e protein fractions of E. contortisiliquum also showed larvicidal activity, highlighting that F2 showed higher larvicidal activity and lower en vironmental toxicity than the CE source. The reduction in the proteolytic activity of larvae fed with crude extra ct and fractions of E. contortisiliquum suggest ed that the trypsin inhibitors ( ITEc) would be resp onsible for larvicidal activity . However the increase in the purification of this inhibitor resulted in loss of larvicidal activity , but the absence of trypsin inhibitor reduced the effectiveness of the fractions , indicating that the ITEC contributes to the larvicidal activity of this extract. Not been observed larvicidal activity and adulticide in rich fraction vicilin, nor evidence of the contribution o f this molecule for the larvicidal activity of the extract. The results show the potential of seeds from plant extracts of Caatinga as a source of active molecules against insects A. aegypti at different stages of its development cycle, since they are comp osed of different active compounds, including protein nature, which act on different mechanisms should result in the death of insec

Crescimento inicial e morfologia foliar em plantas de Mimosa caesalpiniaefolia Benth. Em função do manejo microbiano, sob estresse salino

The sabiá (Mimosa caesalpiniaefolia Benth.) is an endemic species of the Caatinga biome, considered tolerant to salt and water stress. The process of salinization of soil and groundwater and surface water is one of the most important problems of environmental degradation, with its harmful effects being more pronounced in the areas of arid and semiarid regions, and rapidly growing in many parts of the globe, causing problems of the major crop yield. Organic conditioners as barnyard manure, and rice hulls can contribute to reducing the PST, possibly due to the release of CO2 and the production of organic acids during the decomposition of organic matter, and act as sources of calcium and magnesium and inhibit the availability sodium. The intimate association of mycorrhizae and beneficial to plants results in increased uptake of water and nutrients by plants, especially phosphorus, due to their low mobility in soil. The objective of this study was to evaluate the initial growth of thrush seedlings under inoculation with mycorrhizal fungi and fertilized with manure corral and irrigated with water of different salinity levels. The experiment was conducted in greenhouse conditions of vegetation on the premises of the Agricultural School of Jundiaí - UFRN, Campus Macaíba. The adopted statistical design was randomized composed of twelve treatments - three substrates (sterile soil, manure and FMA), four salinity levels (0.2, 1.5, 3.0 and 4.5 dS m-1 ) and five repetitions, totaling sixty experimental units. The results indicate that inoculation with mycorrhizal fungi own contributions to the growth of plants, especially in roots and shoots, which suggests that its application is beneficial in establishing thrush plants in natural conditions, with poor soil in P. Levels salinity caused no effects with statistical significance in plant development, indicating Sabia resistance to it.

Potencial larvicida de extratos de plantas regionais no controle de larvas de Aedes Aegypti (Diptera:Culicidae)

Dengue, amongst the virus illnesses one can get by vectorial transmission, is the one that causes more impact in the morbidity and mortality of world s population. The resistance to the insecticides has caused difficulties to control of vector insect (Aedes aegypti) and has stimulated a search for vegetables with larvicidal activity. The biodiversity of Caatinga is barely known and it is potential of use even less. Some plants of this biome are commercialized in free fairs northeast of Brazil, because of its phytotherapics properties. The vegetables in this study had been selected by means of a questionnaire applied between grass salesmen and natives of the Serido region from Rio Grande do Norte state; culicids eggs had been acquired with traps and placed in container with water for the larva birth. Thirty larvae had been used in each group (a group control and five experimental groups), with four repetitions four times. The vegetables had been submitted to the processes of decoction, infusion and maceration in the standard concentration of 100g of the vegetable of study in 1l of H2O and analyzed after ½, 1, 2, 4, 8, 12, 24 and 48 hours for verification of the average lethal dose (LD50) from the groups with thirty larva. The LD50 was analyzed in different concentrations (50g/l, 100g/l, 150g/l, 200g/l e 300g/l) of Aspidosperma pyrifolium Mart. 48 extracts of rind, leaf and stem of the seven vegetal species: Aspidosperma pyrifolium Mart., Mimosa verrucosa Benth, Mimosa hostilis (Mart.) Benth., Myracrodruon urundeuva Allemão, Ximenia americana L, Bumelia sartorum Mart Zizyphus joazeiro Mart, had been analyzed. The extracts proceeding from the three methods were submitted to the freezedrying, to evaluate and to quantify substances extracted in each process. The results had shown that Aspidosperma pyrifolium Mart. and Myracrodruon urundeuva Allemão are the species that are more distinguished as larvicidal after 24 hours of experiment, in all used processes of extraction in the assays. The Zizyphus joazeiro Mart species has not shown larvicidal activity in none of the assays. In relation to the extraction method, the decoction was the most efficient method in the mortality tax of the A. aegypti larvae