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1.
Int J Pharm Pharm Sci ; 2020 May; 12(5): 54-59
Artigo | IMSEAR | ID: sea-206094

RESUMO

Objective: The present study was designed to investigate phytopromotional effects of Sebacina vermifera on economically and medicinally important aromatic plant - Coriandrum sativum (coriander). Methods: Phytopromotional effects of Sebacina vermifera were evaluated on coriander, under greenhouse and field conditions. The evaluations were carried out with reference to emergence, growth promotion and quantitative as well as the qualitative composition of essential oil. Beside this the overall effects were comparatively assessed with the effects of (a) Phosphate solubilizing bacteria (Pseudomonas fluorescens) (b) Nitrogen-fixing bacteria (Azotobacter chroococcum) on coriander using same parameters. Results: Mycorrhizal fungus (Sebacina vermifera) was observed with the most significant effect in all aspects viz. emergence, growth promotion and quantitative as well as the qualitative composition of essential oil. Conclusion: Based upon the observations, Sebacina vermifera is highly recommended as a potential biological agent that could be applied for phytopromotional effects and economic cultivation of aromatic plants.

2.
Univ. sci ; 20(2): 201-207, may.-ago. 2015. ilus
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-755652

RESUMO

We studied the preservation of Azotobacter chroococcum C26 using three dry polymers: carrageenin, sodium alginate, and HPMC, using a method of accelerated degradation. Bacterial viability, as response variable, was measured at three temperatures in four different times, which was followed by calculation of bacterial degradation rates. Results showed that temperature, time of storage, and protective agent influenced both viability and degradation rates (P<0.05). We observed, using the Arrhenius thermodynamic model, that the use of polymers increased the activation energy of bacterial degradation compared to control. We obtained thermodynamic models for each polymer, based on the Arrhenius equation, which predicted the required time for thermal degradation of the cells at different temperatures. Analysis of the models showed that carrageenin was the best polymer to preserve A. chroococcum C26 since ~ 900 days are required at 4 °C to reduce its viability in two log units. We conclude, therefore, that long-term preservation of A. chroococcum C26 using dry polymers is suitable under adequate preservation and storage conditions.


Se estudió la preservación de Azotobacter chroococcum C26 usando tres polímeros secos: carragenina, alginato de sodio y HPMC, usando un método de degradación acelerada. Viabilidad bacteriana, como variable de respuesta, fue medida a tres temperaturas en cuatro tiempos diferentes, lo cual fue seguido por el cálculo de tasas de degradación bacteriana. Los resultados mostraron que la temperatura, el tiempo de almacenamiento, y el agente protectivo influenciaron tanto la viabilidad como las tasas de degradación (P<0.05). Se observó, usando el modelo termodinàmico de Arrhenius, que el uso de polímeros incremento la energía de activación de degradación bacteriana comparado con el control. Adicionalmente, se obtuvieron modelos para cada polímero, basados en la ecuación de Arrhenius, para predecir el tiempo requerido para la degradación térmica de las células a diferentes temperaturas. El análisis de los modelos mostró que la carragenina fue el mejor polímero para preservar A. chroococcum C26 dado que un tiempo de aproximadamente 900 días a 4 °C son necesarios para reducir en dos unidades logarítmicas la viabilidad. Se concluye, por lo tanto, que la preservación a largo término usando polímeros es eficaz para la preservación de A. chroococcum C26 bajo condiciones adecuadas de preservación y mantenimiento.


Estudamos a preservado do Azotobacter chroococcum C26 utilizando tres polímeros secos: carragenina, alginato de sòdio, e HPMC, utilizando um método de degradado acelerada. Viabilidade bacteriana, como variável de resposta, foi medida a tres temperaturas em quatro momentos diferentes, que foi seguido pelo cálculo das taxas de degradado bacteriana. Os resultados mostraram que a temperatura, tempo de armazenamento, e agente protetor influenciado as taxas de viabilidade e de degradado (P <0,05). Observou-se, utilizando o modelo de Arrhenius termodinàmico, que a utilizac.ao do polímeros de aumento da energia de activado do degradado bacteriana em comparado com o controlo. Adicionalmente, obtivemos modelos termodinámicos para cada polímero, com base na equação de Arrhenius, para prever o tempo necessàrio para a degradação térmica das células a diferentes temperaturas. Análise dos modelos mostrou que a carragenina é o melhor polímero para preservar A. chroococcum C26, porque ~ 900 dias são necessários a 4 °C para reduzir a viabilidade de duas unidades logarítmicas. Nós concluímos, portanto, a preservação a longo prazo de A. chroococcum C26 utilizando polímeros secos é adequado sob condic.öes de preservalo e armazenamento adequadas.

3.
Artigo em Inglês | IMSEAR | ID: sea-163660

RESUMO

Alginates form an important family of biopolymers. These are linear polysaccharides composed of variable amounts of (1–4)-β-D-mannuronic acid and its epimer, α-L-guluronic acid. Currently, commercial alginates are extracted from marine brown algae. Considering the merits of bacterial alginates, optimal fermentation conditions aiming at the maximization of alginate using bacterium Azotobacter chroococcum from different substrates were examined. Whey, molasses, ammonium nitrate, starch, yeast extract, butanol, mannitol, and glucose have been used. The alginate obtained from whey (45.15%), ammonium nitrate (46.02%) and butanol (47.3%) varied. Among the physical stress conditions, the production of alginate was maximum at heat shock 50 0C for 30min (42.96%) followed by 41.29% on UV radiation for 10 min. At pH 7 and 8 the alginate produced was 44.63% and 46.64% respectively. Carbazole reagent was used to recognize alginate; it was lyophilized and quantitated by gas chromatography.

4.
Rev. colomb. biotecnol ; 12(2): 103-115, dic. 2010. tab, graf
Artigo em Espanhol | LILACS | ID: lil-590777

RESUMO

Con el objetivo de incrementar y acelerar el proceso de germinación de las semillas y obtener una alta producción y homogeneidad de plántulas de Carica papaya variedad Maradol en vivero, se evaluó el efecto de tres biofertilizantes aplicados solos o en combinación (Azotobacter chroococcum, Azospirillum brasilense y Glomus intraradices), y un biorregulador del crecimiento vegetal, el ácido giberélico (AG3), en la germinación y el crecimiento vegetal. Se realizó un experimento bajo un diseño completamente al azar con ocho tratamientos y tres repeticiones. A las semillas se les aplicó un pretratamiento germinativo con alternancia de temperatura para superar la dormancia. Los tratamientos simples con A. chroococcum y A. brasilense, incrementaron el porcentaje de germinación a 90,28 y 88,89% respectivamente. Además, con la aplicación de los biofertilizantes y el AG3, la velocidad de germinación se incrementó y el tiempo medio de germinación se redujo. La doble aplicación en semillas y foliar de los biofertilizantes y el AG3 en plántulas mejoró el crecimiento vegetal. La población de A. chroococcum fue mayor cuando se inoculó en combinación con G. intraradices. La prevalencia de colonización de las plántulas inoculadas con G. intraradices varió de 18,53 a 26,67%, con el mayor valor registrado para el tratamiento combinado con A. brasilense. Finalmente, aplicando esta metodología se logró acelerar la germinación, obteniéndose una mayor homogeneidad en la emergencia de las plántulas, disminuyendo así el tiempo de permanencia en el vivero.


In order to increase and accelerate the process of seed germination and obtain a high yield and homogeneity of papaya seedlings cv. Maradol in nurseries, we evaluated the effect of three biofertilizers applied single or in combination (Azotobacter chroococcum, Azospirillum brasilense and Glomus intraradices) and a plant growth bioregulator, the gibberellic acid 3 (AG3), on the germination and subsequent growth of papaya seedlings. An experimental design completely random with eight treatments and three replications were used. The application of a pre-germinal treatment with alternating temperature had to be applied to seeds to overcome dormancy. Single biofertilization with A. chroococcum and A. brasilense, promoted the germination percentage 90.28 y 88.89% respectively. Germination rate could be enhanced and the mean germination time was reduced with the application of biofertilizer and AG3. Both applications on seeds and leaves of biofertilizers and AG3, had a positive effect on plant growth. The population of A. chroococcum was higher in the combined inoculation with G. intraradices. The prevalence of colonization of plants inoculated with G. intraradices ranged from 18.53 to 26.67%, with the greatest values recorded for the treatment involving combined inoculation with A. brasilense. Finally, with the application of this methodology the seed germination rate was improved, as well as the uniformity of seedlings emergence...


Assuntos
Carica/crescimento & desenvolvimento , Carica/embriologia , Carica/fisiologia , Carica/genética , Carica/microbiologia , Carica/química , Fertilizantes/análise , Fertilizantes/efeitos adversos , Fertilizantes/microbiologia , Azospirillum brasilense/isolamento & purificação , Azospirillum brasilense/crescimento & desenvolvimento , Azospirillum brasilense/fisiologia , Azospirillum brasilense/genética , Azospirillum brasilense/imunologia , Azospirillum brasilense/química
5.
Rev. colomb. biotecnol ; 12(1): 94-102, jul. 2010. tab, graf, ilus
Artigo em Espanhol | LILACS | ID: lil-590648

RESUMO

Se evaluó el efecto de diferentes agroquímicos cuyos principios activos se basan en Carboxin: 5,6-dihydro-2-methyl-N-phenyl-1,4-oxathiin-3 carboxamide; Tiram: tetramethylthioperoxydicarbonic diamide; Imidacloprid: (1-(6-cloro6-4-piridinil-metil)-N-nitroimidazolidin-2-ilideneamina); Cipermetrina: (1RS)-cis,trans-3-(2,2-diclorovinil)-2,2-dimetilciclopropano carboxilato de (RS)-ciano-3-Fenoxibencilo; S-metolachloro: (S)-2-cloro-N-(2-etil-6-metil-fenil)-N-(2-metoxi-1-metil-etil)-acetamida; Fluometuron: 1,1-dimetil-3(alfa, alfa, alfa-trifluoro-m-tolil) urea y Glifosato: (N-(fosfonometil) glicina) sobre la viabilidad del inoculante biológico Monibac® - Corpoica cuyo ingrediente activo es la bacteria diazotrófica no simbiótica Azotobacter chroococcum AC1, aplicando las técnicas de concentración mínima inhibitoria y de compatibilidad. Los resultados demostraron la susceptibilidad del microorganismo frente al insecticida cipermetrina al 50% y al ser mezclado con los demás plaguicidas en la dosis utilizada regularmente en campo. Se encontró que no hubo efectos significativos (P < 0.05) en la aplicación de los plaguicidas (Carboxin, Thiram, Imidacloprid, S-metolachloro, Fluometuron y Glifosato) sobre A. chroococcum AC1, bajo las diferentes dosis evaluadas infiriendo que esta bacteria en condiciones de laboratorio es capaz de tolerar estas sustancias químicas mediante diferentes mecanismos fisiológicos sin afectar su crecimiento.


The effect of different agrochemicals whose active ingredient is based on Carboxin: 5,6-dihydro-2-methyl-N-phenyl-1,4-oxathiin-3carboxamide; Tiram: tetramethylthioperoxydicarbonic diamide; Imidacloprid: (1-(6-cloro6-4-pyridinyl-methyl)-N-nitroimidazolidin-2-ilideneamina); Cypermethrin: (1RS)-cis, trans-3-(2.2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate (RS)-cyano-3-phenoxybenzyl; S-metolachlor:(S)-2-chloro-N-(2-ethyl-6-methyl-phenyl)-N-(2-methoxy-1-methyl-ethyl)-acetamide; Fluometuron: 1,1-dimethyl-3 (alpha, alpha, alpha-trifluoro-m-tolyl) urea and Glyphosate: (N-(phosphonomethyl) glycine) on the viability of biological inoculant Monibac ® - Corpoica whose active ingredient is based on non-symbiotic diazotrophic bacteria Azotobacter chroococcum AC1, applying the minimum inhibitory concentration and compatibility techniques. The results demonstrated the susceptibility of the organism Cypermethrin 50% and when it is mixed with other pesticides in the rate used in the field regularly. It was found that there were no significant effects (P< 0,05) of pesticides (Carboxin, Thiram, Imidacloprid, S-metolachlor, Fluometuron and Glyphosate) under the different concentrations tested suggesting that this bacterium is able to tolerate these chemicals by different physiological mechanisms without affecting their growth in laboratory level.


Assuntos
Agroquímicos/administração & dosagem , Agroquímicos/análise , Agroquímicos/farmacologia , Agroquímicos/química , Agroquímicos/síntese química , Inibição de Contato/fisiologia , Inibição de Contato/genética
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