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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Atividade antimicrobiana de extratos vegetais de plantas do estado do tocantins. / Antimicrobial Activity of Plant Extracts from the Tocantins State - Brazil.

Hebert Lima Batista 07 November 2008 (has links)
A busca de novos medicamentos eficases para o combate das infecÃÃes por bactÃrias multiresistentes à uma das grandes preocupaÃÃes da Ãrea cientÃfica mundial, desde o relato de existÃncia de cepas resistentes a penicilina observada por Kirby em 1966. A preocupaÃÃo à crescente devido à disseminaÃÃo destas estirpes resistentes, tanto em ambito ambulatorial quanto hospitalar e a diminuiÃÃo de registro nos Ãltimos anos de novas drogas com potencial de controle das infecÃÃes. No intuito de contribuir com o desenvolvimento de novos fÃrmacos atravÃs de isolamento de molÃculas provenientes de plantas com potencial antimicrobiano, foi proposto o screening dos extratos hexÃnicos, alcoÃlicos 95ÂGL e a 70% de seis plantas - Jenipapo (Genipa americana L.), - Folha da Fortuna (Bryophyllum pinnatum (Lam.) Oken), - Meracilina (Alternanthera cf. brasiliana (L.) Kuntze), - Mangabeira (Lafoensia pacari St. Hil), - Mesocarpo do BabaÃu (Orbignya spp.), - Bacuri (Attalea phalerata Mart.); contra oito estirpes de bactÃrias, cinco Gram-positivas e trÃs Gram-negativas. Os referidos extratos secos de cada planta foram obtidos por masceraÃÃo, seguido de evaporaÃÃo do solvente e liofilizaÃÃo. Estes extratos foram solubilizados em DMSO:H20 â 1:1 atà concentraÃÃes que variaram de 1000 a 1mg/mL para avaliaÃÃo microbiolÃgica, pela tÃcnica de difusÃo em agar, com deposito de 50ÂL do extrato em poÃos de 6x8mm. As bactÃrias ensaiadas demonstraram-se resistentes a todos os extratos hexÃnicos das plantas experimentadas, alÃm dos extratos alcoÃlicos das folhas de A. brasiliana. Os extratos alcoÃlicos 95ÂGL e 70% de folhas de L. pacari e folhas de B. pinnatum inibiram o crescimento de todas as espÃcies de bactÃrias apresentando halos de inibiÃÃo superiores a 15mm e concentraÃÃo mÃnima inibitÃria - CMI entre 250 a 1mg/mL. Os extratos alcoÃlicos 95ÂGL e 70% Mesocarpo de Orbignya spp inibiu o crescimento de bactÃrias gram positivas, com halos de inibiÃÃo maiores que 10 mm e menores de 20 mm e CMI entre 250 a 100mg/mL. Jà o fruto de G. americana e o mesocarpo e epicarpo de A. phalerata inibiram tanto bactÃrias gram positivas como Gram negativas, mas com resistÃncia a vÃrias estirpes para os extratos alcoÃlicos 95ÂGL e 70% com halos de inibiÃÃo superior a 10mm e inferor a 20mm e CMI de 1000 a 500mg/mL. Os resultados da entrecasca da G. americana obtiveram halos de inibiÃÃo entre 10 e 15mm com CMI variando entre 1000 a 250 mg/mL. Posteriorente, o extrato alcoÃlico 70% do Mesocarpo de Orbignya spp foi submetido fracionamento bioguiado por tÃcnicas quÃmicas, cromatograficas e Bioautografia, obtendo 24 fraÃÃes com potencial para atividade antimicrobiana. Assim, a maioria dos extratos ensaiados mostrou-se eficazes contra microrganismos patogÃnicos, compreendendo ser uma fonte promissora de fÃrmacos antimicrobianos. / The research for new drugs efficient to combat of multiresistant bacteria infections is a great concern of the scientific world, since the report of the existence of strains resistant to penicillin followed by Kirby in 1966. Because to spread of resistant strains in hospital and outpatient and lessen records in recent years of new drugs with potential for control these infections. Thought to contribute to development of new drugs and isolament of molecules from plants with antimicrobial potential, was proposed screening of the hexane extract, 95  GL alcohol and 70% of six plants - Jenipapo (Genipa americana L.), -Folha da Fortuna (Bryophyllum pinnatum (Lam.) Oken), -Meracilina (Alternanthera cf. brasiliana (L.) Kuntze ), -Mangabeira (Lafoensia pacari St. Hil), - Mesocarpo do BabaÃu (Orbignya spp.), - Bacuri (Attalea phalerata Mart.); against eight strains of bacteria, five Gram-positive and three Gram-negative strains. All dried extracts of each plant were obtained by masceraÃÃo, followed by evaporation of the solvent and lyophilization. These extracts were solubilized in DMSO: H20 - 1:1 up to concentrations ranging from 1000 to 1mg/ml for microbiological evaluation, the technique of diffusion in agar, with deposit of 50μL of extract in wells of 6x8mm.The bacterias tested showed resistant for hexane extract of all plants, and addition of alcoholic extracts of leaves of A. brasiliana. The extracts alcoholic 95ÂGL and 70% of leaves of L. pacari and leaves of B. pinnatum inhibited growth of all species of bacterias, and showing halos of inhibition greater than 15mm and minimum inhibitory concentration - MIC of 250 to 1mg/ml. The alcoholic extracts and 95ÂGL 70% of mesocarp Orbignya spp inhibited the growth of gram positive bacteria, with halos of inhibition larger than 10 mm and less than 20 mm and MIC of 250 to 100mg/mL. The alcohol extracts 95ÂGL and 70% of G. americana fruit and the A. phalerata mesocarp and epicarp inhibited gram positive and gram-negative bacteria, but with resistance to some strains and demonstrate inhibition halos with 10 to 20mm and MIC of 1000 to 500mg/mL. The results of extracts of sap of G. American show inhibition halos between 10 and 15mm with MIC ranging from 1000 to 250 mg/mL. The alcoholic extract 70% form mesocarp of Orbignya spp was fractionated by chemical techniques guided by biological activity, followed by chromatography and bioautography, were obtained 24 fractions with antimicrobial activity potential. Thus, the most of extracts tested showed to be effective against pathogenic microorganisms, comprising a promising source of antimicrobial agents.
2

Caracterização química e atividades biológicas de Bryophyllum pinnatum (Lam.) Oken

Chibli, Lucas Apolinário 25 July 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-06-17T13:26:30Z No. of bitstreams: 1 lucasapolinariochibli.pdf: 4452333 bytes, checksum: 37e0f0b3c3682a67c7f4efa2b05bd2bd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-17T13:28:59Z (GMT) No. of bitstreams: 1 lucasapolinariochibli.pdf: 4452333 bytes, checksum: 37e0f0b3c3682a67c7f4efa2b05bd2bd (MD5) / Made available in DSpace on 2016-06-17T13:29:00Z (GMT). No. of bitstreams: 1 lucasapolinariochibli.pdf: 4452333 bytes, checksum: 37e0f0b3c3682a67c7f4efa2b05bd2bd (MD5) Previous issue date: 2013-07-25 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Bryophyllum pinnatum (Lam.) Oken (Crassulaceae), conhecida como “folha-da-fortuna”, tem sido largamente utilizada na medicina tradicional, principalmente para o tratamento de inflamações, infecções, feridas, ulcerações e gastrite. O objetivo do presente estudo foi identificar e quantificar constituintes bioativos, bem como avaliar as atividades antioxidante, antibacteriana e anti-inflamatória tópica das folhas de B. pinnatum. O material vegetal seco e pulverizado foi submetido à maceração com etanol seguida de obtenção, por partição, das frações hexânica, diclorometânica, em acetato de etila e butanólica. Constituintes do extrato etanólico e das frações foram identificados por cromatografia líquida de alta eficiência acoplada a detector de ultravioleta e cromatografia com fase gasosa acoplada à espectrometria de massas. Os teores de fenóis e flavonoides totais foram determinados por espectrofotometria e a atividade antioxidante avaliada pelos ensaios com radical DPPH, de poder de redução, sistema de cooxidação β-caroteno/ácido linoleico e bioautografia. A atividade antibacteriana foi investigada pelos métodos de difusão e microdiluição. A atividade anti-inflamatória tópica foi avaliada usando modelos de edema de orelha induzidos por óleo de cróton, ácido araquidônico, fenol, capsaicina, etil-fenil-propiolato e por análise histológica. Os resultados foram demonstrados como média ± erro padrão. Análise de variância seguida do teste de Tukey ou Student-Newman-Keuls foi usada para medir o grau de significância para p < 0,05. Quercetina, rutina, canferol, apigenina 7-O-β-D-glicosídeo e luteolina 7-O-β-D-glicosídeo foram identificados por CLAE-UV, enquanto -amirina por CG-EM. Os teores de fenóis totais variaram de 3,45 a 25,34 g/100 g, enquanto os flavonoides foram de 0,66 a 23,31 g/100 g. Utilizando o método do DPPH, os valores de CE50 variaram entre 9,44 ± 0,01 a 57,29 ± 0,11 μg/mL e o método do poder de redução produziu CE50 de 234,22 ± 0,61 e 1235,17 ± 1,39. Os valores de inibição da peroxidação lipídica foram entre 39,4 e 58,3% e o método de biautografia detectou substâncias com atividade antioxidante. O extrato etanólico e as frações inibiram o crescimento das bactérias testadas, produzindo atividades bactericida e bacteriostática. Concentrações de 0,5 e 1,0 mg/orelha do extrato etanólico reduziram o edema de orelha induzido pelo óleo de cróton em 54,85 e 57,11%, enquanto o edema de orelha induzido pelo ácido araquidônico foi de 41,67, 53,82 e 67,01% nas concentrações de 0,1, 0,5 e 1,0 mg/orelha, respectivamente. O edema induzido pelo fenol foi inibido em 79,73, 33,14 e 33,71% nas concentrações de 0,1, 0,5 e 1,0 mg/orelha, respectivamente. Após tratamento, 0,1 (43,22%), 0,5 (72,53%) e 1,0 mg/orelha (35,16%) do extrato etanólico reduziu o edema de orelha induzido por capsaicina. O edema induzido pelo etil-fenil-propriolato, nas concentrações de 0,1 (75,00%), 0,5 (69,77%) e 1,0 mg/orelha (43,60%) foi inibido. Os resultados do teste crônico de edema de orelha e a análise histológica confirmaram o efeito do extrato etanólico na inibição do processo inflamatório induzido pelo óleo de cróton. Os resultados indicaram que B. pinnatum possui efeitos antioxidante, antibacteriano e anti-inflamatório tópico, justificando o uso popular e destacando a espécie como potencial alvo para a descoberta de novos agentes terapêuticos. / Bryophyllum pinnatum (Lam.) Oken (Crassulaceae), known as "folha-da-fortuna" (leaves-of-fortune), has been widely used in traditional medicine, mainly for the treatment of inflammation, infection, wound, ulcer and gastritis. The aim of the present study was to identify and quantify bioactive constituents, as well as evaluating the antioxidant, antibacterial and topical anti-inflammatory activities of B. pinnatum leaves. Dried and pulverized plant material was subjected to maceration with ethanol followed by partition to obtain the hexanic, dichloromethanic, in ethyl acetate and butanolic fractions. Constituents of the ethanol extract and fractions were identified by high performance liquid chromatography coupled to ultraviolet detector and gas chromatography coupled to mass spectrometry. The total phenols and flavonoids contents were determined by spectrophotometry and the antioxidant activity was evaluated using DPPH, reducing power, β-carotene/linoleic acid co-oxidation system and bioautography assays. The antibacterial activity was investigated by diffusion and microdilution methods. The topical anti-inflammatory activity was evaluated through ear oedema models induced by croton oil, arachidonic acid, phenol, capsaicin, ethyl phenyl propiolate and histological analysis. The results were demonstrated as mean ± standard error. Analysis of variance followed by Tukey or Student-Newman-Keuls test was used to measure the degree of significance of p < 0.05. Quercetin, rutin, kaempferol, apigenin 7-O-β-D-glucoside and luteolin 7-O-β-D-glucoside were identified by HPLC-UV DAD, while -amyrin by GC-MS. The total phenolic content ranged from 3.45 to 25.34 g/100 g, while flavonoids were 0.66 to 23.31 g/100 g. Using the DPPH assay, the values of EC50 ranged from 9.44 ± 0.01 to 57.29 ± 0.11 g/mL and the reducing power assay produced EC50 of 234,22 ± 0,61 and ± 1235.17 ± 1.39. The values of inhibition of lipid peroxidation were between 39,4 and 58,3% and the bioautography assay detected substances with antioxidant activity. The ethanol extract and fractions inhibited the growing of bacteria tested producing bactericidal and bacteriostatic activities. Concentrations of 0.5 and 1.0 mg/ear of the ethanol extract reduced the ear oedema induced by croton oil in 54.85 and 57.11%, while the ear oedema induced by arachidonic acid was inhibited by 41.67, 53.82 and 67.01% at concentrations of 0.1, 0.5 and 1.0 mg/ear, respectively. The phenol-induced oedema was inhibited by 79.73, 33.14 and 33.71% in 0.1, 0.5 and 1.0 mg/ear, respectively. After treatment, 0.1 (43.22%), 0.5 (72.53%) and 1.0 mg/ear (35.16%) of the ethanol extract reduced the ear oedema induced by capsaicin. The phenyl-ethyl propriolato-induced oedema at concentrations of 0.1 (75.00%) 0.5 (69.77%) and 1.0 mg/ear (43.60%) was inhibited. Results from chronic ear oedema test and histological analysis confirmed the effect of the ethanol extract on inhibition of oedema induced by croton oil. The results indicated that B. pinnatum possesses antioxidant, antibacterial and topical anti-inflammatory effects justifying the popular use and highlighting the species as a potential target for the discovery of new therapeutic agents.
3

Composições nanoestruturadas de Bryophyllum pinnatum (Lam.) oken com β-ciclodextrina

Lanna, Elisa Gomes 17 July 2015 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-05-12T13:14:28Z No. of bitstreams: 1 elisagomeslanna.pdf: 3970736 bytes, checksum: 6d637b75ed33e9ab58ac8e2e682d7e88 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-12T15:44:54Z (GMT) No. of bitstreams: 1 elisagomeslanna.pdf: 3970736 bytes, checksum: 6d637b75ed33e9ab58ac8e2e682d7e88 (MD5) / Made available in DSpace on 2017-05-12T15:44:54Z (GMT). No. of bitstreams: 1 elisagomeslanna.pdf: 3970736 bytes, checksum: 6d637b75ed33e9ab58ac8e2e682d7e88 (MD5) Previous issue date: 2015-07-17 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / A Bryophyllum pinnatum(Lam.) Oken (Crassulaceae) é conhecida popularmente como folha-da-fortuna, courona, courona-vermelha, coirama e saião-roxo. Popularmente é usada como agente antimicrobiano (antifúngico e antibacteriano) e para o tratamento de úlceras gástricas, diarreia, vômito, queimaduras e doenças inflamatórias. O objetivo do presente trabalho foi potencializar a bioatividade do seu extrato etanólico através do desenvolvimento de uma composição nanoestruturada, usando -ciclodextrina (CD) como matriz hospedeira, seguida de sua incorporação em formulação semissólida para uso como anti-inflamatório tópico. Inicialmente, o material vegetal seco e pulverizado foi submetido à maceração com etanol seguida de partição, obtendo-se as frações hexânica, diclorometânica, acetato de etila e butanólica. Para o nanoencapsulamento do extrato/frações com βCD, quantidades iguais de extrato/frações e βCD foram pesados e solubilizados em etanol e a solução foi submetida à secagem (40º C) sob agitação. Caracterizações físico-químicas foram realizadas no intuito de mostrar a formação de compostos de inclusão entre a CD e constituintes do extrato e, identificar suas propriedades. Classes de constituintes do extrato/frações foram identificadas através das espectroscopias de UV-Vis e IR. A identificação dos nanoagregados e a avaliação da estabilidade coloidal foram feitas por medidas de espalhamento de luz dinâmico, potencial zeta e condutividade. Análise térmica diferencial (DTA) e termogravimetria (TGA) foram usadas para comprovar o aumento da estabilidade térmica enquanto que ensaios de solubilização foram realizados para mostrar o aumento da solubilidade na presença de CD. Os experimentos de atividade antioxidante do extrato/frações avaliada pelos ensaios com radical DPPH, do poder de redução do Fe3+ e do sistema de cooxidaçãoβ-caroteno/ácido linoleico, permitiram mostrar que a CD foi capaz de melhorar significativamente a atividade antioxidante do extrato etanólico (P < 0,005), fração acetato de etila (P < 0,005) e fração hexânica (P < 0,005), se comparado com o extrato/fração puro. A atividade anti-inflamatória tópica foi avaliada através do modelo de edema de orelha induzida aplicação tópica de óleo de cróton, com posterior análise histológica e ensaio da atividade da enzima mieloperoxidase (MPO). Quando avaliado a atividade anti-inflamatória das formulações semissólidas contendo o composto de inclusão com βCD, percebeu-se uma melhora da atividade quando comparado com as formulações que continham o extrato etanólico na forma livre, mostrando que a complexação dos componentes do extrato com a CD é uma importante estratégia a ser considerada para o desenvolvimento de formulação para uso tópico. / The Bryophyllum pinnatum (Lam.) Oken (Crassulaceae) is popularly known as ―folha-da-fortuna‖, ―courona‖, ―courona-vermelha‖, ―coirama‖ and ―saião-roxo‖. It is popularly used as antimicrobial (antifungal and antibacterial) and for treatment of gastric ulcers, diarrhea, vomiting, burns and inflammatory diseases. The goal of this study was to enhance the bioactivity of the ethanolic extract by developing nanostructured compositions, using β-cyclodextrin (βCD) as host matrix, followed by its incorporation into semisolid formulation for use as anti-inflammatory topic. Initially, the dried and powdered plant material was subjected to maceration with ethanol followed by partition to obtain the hexanic, dichloromethanic, ethyl acetate and butanolic fractions. For the nanoencapsulation of the extract/fractions with βCD, equal amounts of extract/fractions and βCD were weighed and solubilized in ethanol and the solution was subjected to drying (40 °C) under stirring. Physicochemical characterizations were carried out in order to show the formation of inclusion compounds between βCD and constituents of the extract/fraction and, identify their properties. Constituents of the extract/fractions were identified by UV-Vis and IR spectroscopies. The identification of nanoclusters and the evaluation of the colloidal stability was made by dynamic light scattering measurements, zeta potential and conductivity. Differential thermal analysis (DTA) and thermogravimetry (TGA) were used to demonstrate the increase in thermal stability while solubilization tests were performed to show increased solubility in the presence of βCD. The antioxidant activity of the extract/fractions was evaluated by trials with DPPH radical, power reduction of Fe3+ and β-carotene/linoleic acid system, allowed to show that βCD was able to significantly improve the antioxidant activity of ethanol extract (P <0.005), ethyl acetate fraction (P <0.005) and hexane fraction (P <0.005), compared with the extract/fraction pure. The topical anti-inflammatory activity was evaluated through ear edema model induced by croton oil, with subsequent histological analysis and assay of myeloperoxidase activity (MPO). When evaluated the anti-inflammatory activity of semisolid formulations containing the inclusion compound with βCD, it was noticed an improvement in activity when compared to the formulations containing the ethanol extract in the free form, proving that the complexation of the extract components with βCD is an important strategy to consider for the formulation development for topical use.
4

Long-Term Sub-Lethal Effects of Low Concentration Commercial Herbicide (Glyphosate/Pelargonic Acid) Formulation in Bryophyllum Pinnatum

Pokhrel, Lok R., Karsai, Istvan 05 December 2015 (has links)
Potential long-term (~7months) sub-lethal impacts of soil-applied low levels of Roundup herbicide formulation were investigated in a greenhouse environment using the vegetative clones of succulent non-crop plant model, Bryophyllum pinnatum (Lam.) Oken. An eleven day LC50 (concentration that killed 50% of the plants) was found to be 6.25% (~1.25mg glyphosate/mL and 1.25mg pelargonic acid/mL combined), and complete mortality occurred at 12.5%, of the field application rate (i.e., ~20mg glyphosate/mL and 20mg pelargonic acid/mL as active ingredients). While sub-lethal Roundup (1-5%) exposures led to hormesis-characterized by a significant increase in biomass and vegetative reproduction, higher concentrations (≥6.25%) were toxic. A significant interaction between Roundup concentrations and leaf biomass was found to influence the F1 plantlets' biomass. Biomass asymmetry generally increased with increasing Roundup concentrations, indicating that plants were more stressed at higher Roundup treatments but within the low-dose regime (≤5% of the as-supplied formulation). While leaf apex region demonstrated higher reproduction with lower biomass increase, leaf basal area showed lower reproduction with greater biomass increase, in plantlets. The results suggest long-term exposures to drifted low levels of Roundup in soil may promote biomass and reproduction in B. pinnatum.
5

Ekologické determinanty klonálního růstu rostlin / Ecological determinants of plant clonal growth

Martincová, Nina January 2016 (has links)
The aim of this study is to provide a further insight into influence of environment on clonal plants. The study focuses particularly on effects of fertilization level and light availability on production and growth of clonal organs. Three experiments were carried out within the study, targeted to elicit influence of these environmental conditions or clonal interactions on six species of clonal plants. Interspecies dependencies on these conditions was compared, regarding habitat occurrence of these species. A comparison was made also between species producing rhizomes and stolons. The experiments revealed that five of six studied species show significant relationship among at least one environmental condition and parameters of clonal reproduction. Most of the species showed higher elongation and production of clonal organs in relation to fertilization level. On the contrary, only three species reacted significantly to the light availability level by alternation of at least one parameter of clonal reproduction and the light availability level affected each species differently. A strong influence on production and elongation of clonal organs had also a size of a plant. There was not found significant difference in influence of environmental conditions on clonal reproduction among plant families. It...
6

Atividade antibacteriana e ensaio time kill com extratos etanólicos vegetais do cerrado tocantinense contra bactérias resistentes à múltiplos fármacos isoladas de lesões de pés diabéticos

Gatinho, Michele Cezimbra Perim 05 March 2018 (has links)
O desenvolvimento de cepas bacterianas multirresistentes tornou-se uma preocupação global. As plantas medicinais têm sido exploradas como uma fonte potencial terapêutica para o tratamento de várias doenças e para o desenvolvimento de medicamentos mais eficazes contra infecções bacterianas. Assim, o objetivo deste estudo foi avaliar a atividade antibacteriana do extrato de cascas e folhas de Anacardium humile (St.) Hil, extrato de cascas de Davilla nítida (Vahl.) Kubitski, e extrato de folhas de Kalanchoe pinnata (Lam.) Pers. contra bactérias resistentes a múltiplos fármacos isoladas de infecções do pé diabético, e também contra cepas de referência da American Type Culture Collection (ATCC). A atividade antibacteriana foi avaliada pelos métodos de Ágar Disco-Difusão (DD), Microdiluição em Caldo (MC), Ensaio “Checkerboard” e Ensaio “Time-Kill”. O extrato das cascas de Davilla nitida (Vahl.) Kubitski mostrou atividade antibacteriana expressiva contra todos os grupos de bactérias testadas. O método de microdiluição em caldo foi mais sensível que o método disco-difusão para determinar a atividade antibacteriana presente no extrato das cascas. O extrato de cascas inibiu o crescimento de bactérias com altos níveis de resistência aos antibióticos, como Pseudomonas spp. (100,00%), Enterobacter spp. (88,89%), Staphylococcus aureus (54,55%), Streptococcus pneumoniae (75,00%), Staphylococcus saprophyticus (92,86%). A combinação do extrato das cascas com antibióticos resultou em efeito aditivo contra a maioria das cepas testadas. O perfil cinético de tempo de morte do extrato de cascas mostrou propriedades bactericidas tempo-dependentes. Nossos resultados sugerem a presença de compostos bioativos nesta planta que podem ser utilizados para o desenvolvimento de novos agentes antibacterianos. O extrato de folhas de Kalanchoe pinnata (Lam.) Pers. mostrou atividade antibacteriana contra Citrobacter spp. (100,00%), Citrobacter youngae (ATCC-29935) (100,00%), Enterobacter spp. (33,33%), Pseumodonas spp. (66,67%), Pseudomonas aeruginosa (ATCC-27853) (100,00%). O extrato de folhas quando associado com antibiótico amoxicilina/ácido clavulânico ou cefoxitina não evidenciou qualquer potencialização da atividade antibacteriana contra as bactérias Gram-positivas e Gram-negativas, sugerindo que extrato e antibióticos possuem mecanismos independentes relacionados à inibição do crescimento bacteriano. Nossos resultados mostraram que o extrato etanólico das folhas de Kalanchoe pinnata (Lam.) Pers. teve uma boa atividade antimicrobiana contra algumas bactérias resistentes a múltiplos fármacos. Entretanto, estudos adicionais e mais específicos são recomendados para determinar a eficácia deste extrato no tratamento de infecções bacterianas. O extrato das cascas e folhas de Anacardium humile (St.) Hil, tanto no método Disco-difusão quanto em microdiluição em caldo, inibiu significantemente o crescimento das bactérias Gram-positivas e Gram-negativas, como também o crescimento das bactérias comumente encontradas em lesões de pés diabéticos. Pelo método “Checkerboard”, a combinação do extrato das cascas (35,00%) e folhas (40,00%) sobre as bactérias Gram-negativas apresentaram efeitos sinérgicos semelhantes, enquanto que para as bactérias Gram-positivas, os extratos das folhas (45,00%) apresentaram um efeito sinérgico mais efetivo do que os extratos das cascas (17,50%). O perfil cinético “Time-Kill” apresentou atividade bactericida com propriedades dose e tempo dependente, sugerindo que os extratos das cascas e folhas podem potencializar os efeitos dos antibióticos, o que sugere que os extratos de Anacardium humile (St.) Hil podem ser usados com uma fonte alternativa de pesquisa para agentes antibacterianos com ação em bactérias Gram-positivas e Gram-negativas resistentes a multidrogas. No entanto, o isolamento dos compostos bioativos e estudos adicionais devem ser realizados para entender os mecanismos de ação bactericida, para definir a real eficácia e os efeitos tóxicos. / Development of multidrug resistant bacterial strains has become a global concern. Medicinal plants have been explored as a source of molecules with therapeutic potential for the treatment of various diseases and to the development of better drug against bacterial infections. Thus, the aim of this study was to evaluate the antibacterial activity of the bark and leaves extracts of Anacardium humile (St.) Hil, bark extract of Davilla nitida (Vahl.) kubitski, of leaf extract of Kalanchoe pinnata (Lam.) Pers. and against multidrug resistant bacteria isolated from diabetic foot infections, and also of reference strains from the American Type Culture Collection (ATCC). Antibacterial activity of the bark extract was evaluated by agar Disk-Diffusion (DD), Broth Dilution (BD), “Checkerboard” and “Time-Kill” methods. The bark extract of Davilla nitida (Vahl.) kubistki showed a significant antibacterial activity against all groups of bacteria tested. Broth dilution was more sensitive for determining the antibacterial activity of the bark extract than the Disk-Difusion method. The bark extract inhibited the growth of bacteria with high-levels of antibiotic-resistance, such as Pseudomonas spp. (100,00%), Enterobacer spp. (88,89%), Staphylococcus aureus (54,55%), Streptococcus pneumoniae (75,00%), Staphylococcus saprophyticus (92,86%). The combination of extract with antibiotics resulted in an additive effect against most of the strains tested. “Time-Kill” kinetics profiles of bark extract showed bactericidal and time-dependent properties. Our results suggest the presence of bioactive compounds in this plant that could be useful for the development of new antibacterial agents. The leaf extract of Kalanchoe pinnata (Lam.) Pers. showed antibacterial activity against Citrobacter spp. (100,00%), Citrobacter youngae (ATCC-29935) (100,00%), Enterobacer spp. (33.33%), Pseumodonas spp. (66.67%), Pseudomonas aeruginosa (ATCC-27853) (100.00%). Extract of leaf associated with amoxicillin/clavulanic acid or cefoxitin antibiotics did not show any potentiation of antibacterial activity against both Gram-positive and Gram-negative bacteria, suggesting that extract and antibiotics have independent mechanisms related to inhibition of bacterial growth. Our results showed that the ethanolic leaf extract of Kalanchoe pinnata (Lam.) Pers. had a good antimicrobial activity against some multidrug resistant bacteria. However, further and more specific studies, are recommended to determine the efficacy of this extract in the treatment of bacterial infections. Barks and leaves extracts of Anacardium humile (St.) Hil, both in the Disk-Difusion and Broth Dilution methods, inhibited the growth of Gram-positive and Gram-negative bacteria, as well as the growth of bacteria commonly found in diabetic foot lesions. By the “Checkerboard” method, the combination of bark extract (35,00%) and leaves (40,00%) on Gram-negative bacteria had similar synergistic effects, while for Gram-positive bacteria, leaf extracts (45,00%) presented a synergistic effect more effective than the bark extracts (17,50%). The “Time-Kill” kinetic profile showed bactericidal activity with dose and time-dependent properties, suggesting that bark and leaf extracts may potentiate the effects of antibiotics, suggesting that Anacardium humile (St.) Hil extracts can be used with an alternative source of research for antibacterial agents acting on multidrug resistant Gram- positive and Gram- negative bacteria. However, the isolation of bioactive compounds and additional studies should be performed to understand the mechanisms of bactericidal action, to define real efficacy and toxic effects.
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Vliv prasete divokého na vegetaci semixerotermních trávníků / Effect of wild boar on dry grasslands

Horčičková, Eva January 2010 (has links)
The study was focused on disturbances by wild boar (Sus scrofa) and their impact on vegetation of semi-dry grasslands (Festuco-Brometea) dominated by Brachypodium pinnatum. The research was conducted in military area Hradiště in hilly region of the Doupovské hory. Wild boar rooting activities is main source of disturbances regime in this abandoned, previously agricultural area. The vegetation of artificial small scale soil disturbances was compared to undisturbed control plots and vegetation of natural disturbances by wild boar. Experimental plots were established during the summer 2007. Consequently a vegetation survey of these plots was carried out and soil was mechanically disturbed. Succession on disturbances was annually monitored. The surrounding natural disturbances were also mapped three times a year as a potential source of diaspores and to assess their frequency and effect on the landscape level. The list of species in the 2m, 4m and 16m distance from the experimental plot was also made. Results: Disturbances by wild boar increased species diversity and spatial heterogeneity of semi-dry grasslands. There were some species found on experimental plot, which were present not in the surrounding matrix. Most of them belong to hemicryptophytes and species with long-term persistent diaspores. Presence of...

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