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1.
Rev. biol. trop ; Rev. biol. trop;64(4): 1505-1518, oct.-dic. 2016. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-958230

RESUMO

Abstract:The productivity of arid legumes, such as Clusterbean (Cyamopsis tetragonoloba), Cowpea (Vigna unguiculata), Moth bean (Vigna aconitifolia) and Horse gram (Macrotyloma uniflorum), may remain stagnant over decades because of their high susceptibility to root diseases. Besides, there is a limitation on the information about molecular diagnosis and intraspecific genetic variability of root pathogens in arid legumes. To contribute in this field, we assessed a total of 52 isolates from 88 root samples that were found infected with fungal pathogens in Jodhpur, Jaipur and Bikaner Districts of Rajasthan. Diseased roots samples were analyzed following standard microbiological methods for fungus extraction and purification, and for genetic studies. Irrespective of the geographical location from where the diseased samples were collected, all pathogen isolates were clustered in RAPD dendrograms as per their respective genera. Phylogram, based on multiple sequence alignment, revealed that different genera (i.e. Fusarium, Neocosmospora and Syncephalastrum), separated from each other, and species within the same genera, clustered together with their reference sequences with apreciable bootstrap values. Out of 20 representative isolates representing each cluster and all outgroups sequenced, eight were molecularly identified as Neocosmospora vasinfecta, five as Fusarium solani, two as Neocosmospora striata, two as Fusarium acutatum, one as Syncephalastrum monosporum, one as Fusarium oxysporum and one as Fusarium species. The root pathogens of the arid legumes were found neither restricted to a geographical location nor were host specific in nature. Fusarium solani wilt in cowpea and seedling rot in moth bean, F. oxysporum wilt in moth bean, F. acutatum damping off in cowpea and Clusterbean, Fusarium sp. seedling rot in Clusterbean, Neocosmospora striata root rot in cowpea and wilt in Clusterbean and Syncephalastrum monosporum root rot in Clusterbean were molecularly identified as new fungal records as pathogens causing root diseases in arid legumes. Rev. Biol. Trop. 64 (4): 1505-1518. Epub 2016 December 01.


Resumen:La producción de leguminosas resistentes a sequías como Cyamopsis tetragonoloba, Vigna unguiculata, Vigna aconitifolia y Macrotyloma uniflorum, puede permanecer inactiva durante décadas debido a su alta susceptibilidad a enfermedades en las raíces. Además, hay información limitada relacionada con el diagnóstico molecular y la variabilidad genética intraespecífica de patógenos de raíces en estas leguminosas resistentes a sequías. Para contribuir en esta área, evaluamos un total de 52 extractos de 88 raíces infectadas con patógenos fúngicos en los distritos de Jodhpur, Jaipur y Bikaner de Rajastán. Las muestras de raíces infectadas se analizaron siguiendo los métodos estándar de microbiología para extracción y purificación de hongos y para estudios genéticos. Independientemente del sitio donde se recolectaron las muestras contaminadas, todos los extractos patógenicos se agruparon en dendrogramas RAPD en cada uno de sus respectivos géneros. El filograma, basado en alineamiento de secuencias múltiples reveló que distintos géneros (Fusarium, Neocosmospora y Syncephalastrum) separados entre ellos y especies del mismo género se agrupan con sus secuencias de referencia con valores de bootstrap significativos. De cada 20 extractos representantes de cada agrupamiento y todos los grupos externos secuenciados, ocho fueron identificados molecularmente como Neocosmospora vasinfecta, dos como Fusarium acutatum, una como Syncephalastrum monosporum, una como Fusarium oxysporum y una como Fusarium. Los patógenos de estas leguminosas resistentes a sequías no están restringidos por la localidad ni por un hospedero específico. Fusarium solani que marchita el frijol de vaca y pudre la semilla de Vigna aconitifolia, F. oxysporum que marchita a Vigna aconitifolia, F. acutatum que marchita a Vigna unguiculata y Cyamopsis tetragonoloba, Fusarium sp. que pudre la semilla de Cyamopsis tetragonoloba, Neocosmospora striata que pudre la raíz de Vigna unguiculata y marchita a Cyamopsis tetragonoloba y, Syncephalastrum monosporum que pudre la raíz en Cyamopsis tetragonoloba, fueron identificados molecularmente como nuevos registros de patógenos fúngicos que causan daños en las raíces de leguminosas resistentes a sequías.


Assuntos
Doenças das Plantas/microbiologia , Técnicas de Diagnóstico Molecular/métodos , Vigna/microbiologia , Fusarium/isolamento & purificação , Hypocreales/isolamento & purificação , Fabaceae/microbiologia , Mucorales/isolamento & purificação , Variação Genética , DNA Fúngico , Raízes de Plantas/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Polimorfismo de Nucleotídeo Único , Vigna/genética , Hypocreales/genética , Índia , Fabaceae/genética
2.
Talanta ; 159: 395-400, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27474323

RESUMO

The present article describes a portable and low cost fluorescence set-up designed and characterized for in-situ screening of Ochratoxin A (OTA) in cocoa samples at field settings. The sensing module (the set up) consists of a LED with the wavelength of 370-380nm and a color complementary metal oxide semiconductor (CMOS) micro-camera inbuilt at upright position of a black box to obtain an image of the sensing molecule. It allows the user to get an image of the sensing analytes under excitation conditions and process the image in order to predict the toxicity of the samples. The image capturing and processing of the system was based on the OTA concentration in the sample and analyzed data can be presented as RGB values. For each concentration of the OTA, the R, G, B co-ordinates were obtained and plotted to quantify actual OTA presents in the sample. Moreover, the system was tested for real sample analysis using cocoa contaminated with OTA. The system could detect OTA as low as 1.25ng/ml with the maximum recovery of 87.5% in cocoa samples. The OTA was extracted in 1% NaHCO3 and cleaned up using molecular imprinted polymer column (MIP). The method demonstrated a good linear range between 1.25 and 10ng/ml. The obtained results were cross validated using chromatographic method HPLC and also compared with commercially available fluorescence instrument. The developed fluorescence setup is simple, economical, and portable with added advantages of digital image processing. The system could be deployable to cocoa fields for monitoring of OTA in quick successions. It is noteworthy to mention that this is the first report of such portable fluorescence setup where, OTA sensing was explored.


Assuntos
Cacau/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Ocratoxinas/análise , Fluorescência , Análise de Alimentos/economia , Limite de Detecção
3.
Rev Biol Trop ; 64(4): 1505-18, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29465913

RESUMO

The productivity of arid legumes, such as Clusterbean (Cyamopsis tetragonoloba), Cowpea (Vigna unguiculata), Moth bean (Vigna aconitifolia) and Horse gram (Macrotyloma uniflorum), may remain stagnant over decades because of their high susceptibility to root diseases. Besides, there is a limitation on the information about molecular diagnosis and intraspecific genetic variability of root pathogens in arid legumes. To contribute in this field, we assessed a total of 52 isolates from 88 root samples that were found infected with fungal pathogens in Jodhpur, Jaipur and Bikaner Districts of Rajasthan. Diseased roots samples were analyzed following standard microbiological methods for fungus extraction and purification, and for genetic studies. Irrespective of the geographical location from where the diseased samples were collected, all pathogen isolates were clustered in RAPD dendrograms as per their respective genera. Phylogram, based on multiple sequence alignment, revealed that different genera (i.e. Fusarium, Neocosmospora and Syncephalastrum), separated from each other, and species within the same genera, clustered together with their reference sequences with apreciable bootstrap values. Out of 20 representative isolates representing each cluster and all outgroups sequenced, eight were molecularly identified as Neocosmospora vasinfecta, five as Fusarium solani, two as Neocosmospora striata, two as Fusarium acutatum, one as Syncephalastrum monosporum, one as Fusarium oxysporum and one as Fusarium species. The root pathogens of the arid legumes were found neither restricted to a geographical location nor were host specific in nature. Fusarium solani wilt in cowpea and seedling rot in moth bean, F. oxysporum wilt in moth bean, F. acutatum damping off in cowpea and Clusterbean, Fusarium sp. seedling rot in Clusterbean, Neocosmospora striata root rot in cowpea and wilt in Clusterbean and Syncephalastrum monosporum root rot in Clusterbean were molecularly identified as new fungal records as pathogens causing root diseases in arid legumes.


Assuntos
Fabaceae/microbiologia , Fusarium/isolamento & purificação , Hypocreales/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Mucorales/isolamento & purificação , Doenças das Plantas/microbiologia , Vigna/microbiologia , DNA Fúngico , Fabaceae/genética , Fusarium/genética , Variação Genética , Hypocreales/genética , Índia , Mucorales/genética , Doenças das Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Técnica de Amplificação ao Acaso de DNA Polimórfico , Vigna/genética
4.
Braz. j. microbiol ; Braz. j. microbiol;38(4): 773-779, Oct.-Dec. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-473497

RESUMO

A moderately cold active, extracellular alkaline protease producing bacterium was isolated from a fresh water lake. The isolate was found to be a gram-positive, rod shaped organism later identified as Bacillus cereus MTCC 6840. The bacterium produced the maximum amount of enzyme when allowed to grow for 24 h at temperature 25º and pH 9.0. Among a variety of substrates used, fructose as a carbon source and a combination of yeast extract and peptone as nitrogen source, supported the maximum protease production by the organism (120 U/ml). Fe++ and Co++ stimulated the enzyme activity whereas Ca++, Cu++, K+, Mg++ and Mn++ inhibited it to different extents. The protease was found to be highly stable in the presence of NaCl, SDS and acetone. Treatment with EDTA and PMSF resulted in the considerable loss of enzyme activity. The enzyme was found to be optimally active at pH 9.0 and temperature 20ºC.


Uma bactéria produtora de protease alcalina extracelular, moderadamente ativa no frio, foi isolada da água de um lago. Trata-se de um bacilo Gram positivo, identificado como Bacillus cereus MTCC6840. A maior produção da enzima foi em 24h a 25ºC e pH 9,0. A produção máxima de protease (120 U/ml) ocorreu quando foi utilizada frutose como fonte de carbono e uma combinação de extrato de levedura com peptona como fonte de nitrogênio. Fe++ e Co++ estimularam a atividade da enzima, enquanto Ca++, Cu++, K+,Mg++ e Mn++ tiveram efeito inibitório, com intensidades diferentes. A protease permaneceu estável na presença de NaCl, SDS e acetona. O tratamento com EDTA e PMSF causou uma significativa perda na atividade. A enzima apresentou atividade ótima em pH 9,0 e temperatura de 20ºC.

5.
Artigo em Inglês | VETINDEX | ID: vti-444184

RESUMO

A moderately cold active, extracellular alkaline protease producing bacterium was isolated from a fresh water lake. The isolate was found to be a gram-positive, rod shaped organism later identified as Bacillus cereus MTCC 6840. The bacterium produced the maximum amount of enzyme when allowed to grow for 24 h at temperature 25º and pH 9.0. Among a variety of substrates used, fructose as a carbon source and a combination of yeast extract and peptone as nitrogen source, supported the maximum protease production by the organism (120 U/ml). Fe++ and Co++ stimulated the enzyme activity whereas Ca++, Cu++, K+, Mg++ and Mn++ inhibited it to different extents. The protease was found to be highly stable in the presence of NaCl, SDS and acetone. Treatment with EDTA and PMSF resulted in the considerable loss of enzyme activity. The enzyme was found to be optimally active at pH 9.0 and temperature 20ºC.


Uma bactéria produtora de protease alcalina extracelular, moderadamente ativa no frio, foi isolada da água de um lago. Trata-se de um bacilo Gram positivo, identificado como Bacillus cereus MTCC6840. A maior produção da enzima foi em 24h a 25ºC e pH 9,0. A produção máxima de protease (120 U/ml) ocorreu quando foi utilizada frutose como fonte de carbono e uma combinação de extrato de levedura com peptona como fonte de nitrogênio. Fe++ e Co++ estimularam a atividade da enzima, enquanto Ca++, Cu++, K+,Mg++ e Mn++ tiveram efeito inibitório, com intensidades diferentes. A protease permaneceu estável na presença de NaCl, SDS e acetona. O tratamento com EDTA e PMSF causou uma significativa perda na atividade. A enzima apresentou atividade ótima em pH 9,0 e temperatura de 20ºC.

6.
Semin Respir Crit Care Med ; 25(6): 619-28, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16088505

RESUMO

Despite improved understanding of the pathophysiology of shock and significant advances in technology, it remains a serious problem associated with high morbidity and mortality. Early treatment is essential but is hampered by the fact that signs and symptoms of shock appear only after the shock state is well established and the body's compensatory mechanisms have started to fail. Although the causes of shock are varied, the basic abnormality in all varieties is tissue and cellular dysoxia. In this overview we discuss the definition, classification and pathogenesis of shock in light of the recent advances in our understanding of its mechanisms. The epidemiology, diagnosis, and management of the various types of shock are also briefly discussed.

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