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1.
J Family Med Prim Care ; 2(1): 47-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24479043

RESUMEN

INTRODUCTION: The partogram has been heralded as one of the most important advances in modern obstetric care. However, some healthcare practitioners, especially in high-income countries, have questioned its effectiveness. The purpose of this study is to evaluate prospectively the use of a paperless partogram as a bedside tool in the management of labor. MATERIALS AND METHODS: Women were invited to participate in the trial if they were at 36 to 42 weeks of gestation, and carrying a singleton pregnancy, with a cephalic presentation. All women who met the criteria and gave informed consent were included in the study till the required sample size of 91 was obtained. Progress of labor was monitored on the basis of Alert estimated time of delivery (ETD) and Action ETD. At the time of the Action ETD, if woman had not yet delivered, a diagnosis of abnormal labor was made and arrangements were made for emergency obstetric care. RESULTS: Out of 91 women who participated in the study 55 (60%) were primigravida and 36 (40%) were multipara. The mean age of the participants was 25.36 years and the mean duration gestation was 281.9 days. The mean duration for delivery after Alert ETD was 4.3 hours. In our study, out of 91 participants, labor was induced only in 13% of the cases. The mean duration for delivery after Alert ETD was 4.7 ± 1.9 hours in the primigravida and 3.7 ± 1.8 hours in multipara, but these differences were not statistically significant. CONCLUSION: In our study, the paperless partogram was found to be convenient and effective in the management of labor. The mean duration for delivery after Alert ETD was 4.3 hours in our study, which was similar to the World Health Organization's (WHO) recommendation for partograms, with a four-hour action line, denoting the timing of intervention for prolonged labor.

2.
Indian J Microbiol ; 50(1): 2-11, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23100801

RESUMEN

1,2-Propanediol (propylene glycol) is an existing commodity chemical and can be produced from renewable resources using microbes. By virtue of being a natural product, relevant biochemical pathways can be harnessed into fermentation processes to produce 1,2-propanediol. In the present review, the chemical process and different biological strategies for the production of 1,2-propanediol are reviewed and compared with the potentials and limitations of all processes. For the successful commercial production of this diol, it is necessary to establish the metabolic pathways and production hosts (microorganisms), which are capable of delivering final product with high yields and volumetric productivity. Three pathways which have been recognized for 1,2-propanediol production are discussed here. In the first, de-oxy sugars like fucose and rhamnose are used as the carbon sources, while in the other route, the glycolytic intermediate-dihydroxyacetonephosphate (DHAP) is used to produce 1,2-propanediol via the formation of methylglyoxal. A new pathway of 1,2-propanediol production by lactic acid degradation under anoxic conditions and the enzymes involved is also discussed. The production of this diol has gained attention because of their newer applications in industries such as polymers, food, pharmaceuticals, textiles, etc. Furthermore, improvement in fermentation technology will permit its uses in other applications. Future prospect in the light of the current research and its potential as a major bulk chemical are discussed.

3.
Bioresour Technol ; 99(7): 2544-51, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17570660

RESUMEN

Tannase from Penicillium variable IARI 2031 was purified by a two-step purification strategy comprising of ultra-filtration using 100 kDa molecular weight cutoff and gel-filtration using Sephadex G-200. A purification fold of 135 with 91% yield of tannase was obtained. The enzyme has temperature and pH optima of 50 degrees C and 5 degrees C, respectively. However, the functional temperature range is from 25 to 80 degrees C and functional pH range is from 3.0 to 8.0. This tannase could successfully be immobilized on Amberlite IR where it retains about 85% of the initial catalytic activity even after ninth cycle of its use. Based on the Michaelis-Menten constant (Km) of tannase, tannic acid is the best substrate with Km of 32 mM and Vmax of 1.11 micromol ml(-1)min(-1). Tannase is inhibited by phenyl methyl sulphonyl fluoride (PMSF) and N-ethylmaleimide retaining only 28.1% and 19% residual activity indicating that this enzyme belongs to the class of serine hydrolases. Tannase in both crude and crude lyophilized forms is stable for one year retaining more than 60% residual activity.


Asunto(s)
Hidrolasas de Éster Carboxílico/aislamiento & purificación , Enzimas Inmovilizadas/aislamiento & purificación , Penicillium/enzimología , Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Hidrolasas de Éster Carboxílico/metabolismo , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Estabilidad de Enzimas , Enzimas Inmovilizadas/metabolismo , Concentración de Iones de Hidrógeno , Peso Molecular , Especificidad por Sustrato
4.
Biotechnol Lett ; 30(4): 631-5, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18038219

RESUMEN

Cheese whey was the most suitable substrate for production of lactic acid under anaerobic conditions by Entercoccus flavescens which, on supplementating with corn steep liquor (5% v/v) and 10 mM CaCO(3) at pH 5.5, 37 degrees C, yielded 12.6 g lactic acid/l in 36 h. Production was scaled up to a 10 l bioreactor under controlled pH and continuous CO(2) supply and gave 28 g lactic acid/l in 30 h resulting in a net 8.7-fold increase in production as compared to unoptimized conditions.


Asunto(s)
Queso , Ácido Láctico/biosíntesis , Zea mays/química , Anaerobiosis , Enterococcus/metabolismo , Fermentación , Microbiología Industrial/métodos
5.
Appl Biochem Biotechnol ; 142(2): 158-67, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18025577

RESUMEN

Response surface methodology (RSM) was employed for optimization of medium components and cultural parameters in cost effective cane molasses based medium for attaining high yield of succinic acid. The important factors obtained by "one-variable-at-a-time-approach" (cane molasses, corn steep liquor, sodium carbonate, and inoculum density) were further optimized by RSM. The optimum values of the parameters obtained through RSM (cane molasses 12.5%, corn steep liquor 7.5%, and sodium carbonate 25 mM) led to almost double yield of succinic acid (15.2 g/l in 36 h) as against "one-variable-at-a-time-approach" (7.1 g/l in 36 h) in 500-ml anaerobic bottles containing 300-ml cane molasses based medium. Subsequently, in 10-l bioreactor succinic acid production from Escherichia coli was further improved to 26.2 g/l in 30 h under conditions optimized through RSM. This fermentation-derived succinic acid will definitely help in replacing existing environmentally hazardous and cost-intensive chemical methods for the production of succinic acid.


Asunto(s)
Reactores Biológicos/economía , Escherichia coli/metabolismo , Microbiología Industrial/métodos , Ácido Succínico/metabolismo , Análisis Costo-Beneficio , Medios de Cultivo/economía , Escherichia coli/crecimiento & desarrollo , Fermentación , Modelos Estadísticos , Saccharum/química
6.
Anaerobe ; 13(2): 50-6, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17303449

RESUMEN

A statistical approach response surface methodology (RSM) was used to study the production of succinic acid from Bacteroides fragilis. The most influential parameters for succinic acid production obtained through one-at-a-time method were glucose, tryptone, sodium carbonate, inoculum size and incubation period. These resulted in the production of 5.4gL(-1) of succinic acid in 48h from B. fragilis under anaerobic conditions. Based on these results, a statistical method, face-centered central composite design (FCCCD) falling under RSM was employed for further enhancing the succinic acid production and to monitor the interactive effect of these parameters, which resulted in a more than 2-fold increase in yield (12.5gL(-1) in 24h). The analysis of variance (ANOVA) showed the adequacy of the model and the verification experiments confirmed its validity. On subsequent scale-up in a 10-L bioreactor using conditions optimized through RSM, 20.0gL(-1) of succinic acid was obtained in 24h. This clearly indicated that the model stood valid even on large scale. Thus, the statistical optimization strategy led to an approximately 4-fold increase in the yield of succinic acid. This is the first report on the use of FCCCD to improve succinic acid production from B. fragilis. The present study provides useful information about the regulation of succinic acid synthesis through manipulation of various physiochemical parameters.


Asunto(s)
Bacteroides fragilis/metabolismo , Modelos Estadísticos , Ácido Succínico/metabolismo , Anaerobiosis , Análisis de Varianza , Carbonatos/metabolismo , Glucosa/metabolismo , Peptonas/metabolismo , Factores de Tiempo
7.
Bioresour Technol ; 98(2): 260-5, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16524725

RESUMEN

A highly thermostable alkaline amylase producing Bacillus sp. PN5 was isolated from soil, which yielded 65.23 U mL(-1) of amylase in medium containing (%) 0.6 starch, 0.5 peptone and 0.3 yeast extract at 60 degrees C, pH 7.0 after 60 h of incubation. Maximum amylase activity was at pH 10.0 and 90 degrees C. The enzyme retained 80% activity after 1 h at pH 10.0. It exhibited 65% activity at 105 degrees C and had 100% stability in the temperature range between 80 and 100 degrees C for 1 h. In addition, there was 86.36% stability after 1-h incubation with sodium dodecylsulphate. These properties indicated possible use of this amylase in starch saccharification and detergent formulation.


Asunto(s)
Amilasas/metabolismo , Bacillus/enzimología , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Especificidad por Sustrato , Temperatura
8.
Can J Microbiol ; 52(9): 893-902, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17110982

RESUMEN

The effect of process optimization on succinic acid production by Escherichia coli W3110 and on enzymes involved in the reverse tricarboxylic acid cycle was studied. Approximately, 7.02 g L-1 of succinic acid was produced in 60 h at pH 7.0 in 500 mL anaerobic bottles containing 300 mL of the medium, wherein the sucrose concentration was 2.5%, the ratio of tryptone to ammonium hydrogen phosphate was 1:1, and the concentration of magnesium carbon ate was 1.5%. When these optimized fermentation conditions were employed in a 10 L bioreactor, 11.2 g L-1 of succinic acid was produced in 48 h. This is a 10-fold increase in succinic acid production from the initial titer of 0.94 g L-1. This clearly indicates the importance of process optimization, where by manipulating the media composition and production conditions, a remarkable increase in the production of the desired biomolecule can be obtained. The production of succinic acid is a multi-step reaction through the reverse tricarboxylic acid cycle. A linear relationship was observed between succinic acid production and the enzyme activities. The enzyme activities were found to increase in the order phospho-enol-pyruvate carboxylase

Asunto(s)
Ciclo del Ácido Cítrico , Escherichia coli/metabolismo , Ácido Succínico/metabolismo , Anaerobiosis , Reactores Biológicos/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Fermentación , Concentración de Iones de Hidrógeno , Microbiología Industrial/métodos , Iones/metabolismo , Iones/farmacología , Magnesio/metabolismo , Magnesio/farmacología , Peptonas/metabolismo , Peptonas/farmacología , Fosfatos/metabolismo , Fosfatos/farmacología , Fosfoenolpiruvato Carboxilasa/metabolismo , Sacarosa/metabolismo , Sacarosa/farmacología , Temperatura
9.
Anaerobe ; 12(5-6): 231-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16978889

RESUMEN

We report the effect of different physiological and nutritional parameters on succinic acid production from Bacteroides fragilis. This strain initially produced 0.70gL(-1) of succinic acid in 60h. However, when process optimization was employed, 5.4gL(-1) of succinic acid was produced in medium consisting of glucose (1.5%); tryptone (2.5%); Na(2)CO(3) (1.5%), at pH 7.0, when inoculated with 4% inoculum and incubated at 37 degrees C, 100rpm for 48h. A marked enhancement in succinic acid production was observed when the optimized conditions were employed in a 10L bioreactor. A total of 12.5gL(-1) of succinic acid was produced in 30h. This is approximately 12-fold increase in succinic acid production when compared to the initial un-optimized medium production. This enhancement in succinic acid production may be due to the control of CO(2) supply and the impeller speed. This is also resulted in the reduction of the production time. The present study provides useful information to the industrialists seeking environmentally benign technology for the production of bulk biomolecules through manipulation of various chemical parameters.


Asunto(s)
Bacteroides fragilis/metabolismo , Reactores Biológicos/microbiología , Microbiología Industrial/métodos , Ácido Succínico/metabolismo , Anaerobiosis/fisiología , Medios de Cultivo/química , Medios de Cultivo/metabolismo , Fermentación/fisiología , Ácido Succínico/aislamiento & purificación
10.
Bioresour Technol ; 97(13): 1443-8, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16162408

RESUMEN

The most influential parameters for succinic acid production obtained through one at a time method were sucrose, tryptone, magnesium carbonate, inoculum size and incubation period. These resulted in the production of 7.0 g L(-1) of succinic acid in 60 h from Escherichia coli W3110 under anaerobic conditions. Based on these results, a statistical method, face centered central composite design (FCCCD) falling under response surface method (RSM) was employed for further enhancing the succinic acid production and to monitor the interactive effect of these parameters, which resulted in a twofold increase in yield (14.3 g L(-1) in 48 h). The analysis of variance (ANOVA) showed the adequacy of the model and the verification experiments confirmed its validity. On subsequent scale-up in a 10-L bioreactor using conditions optimized through RSM, 24.2 g L(-1) of succinic acid was obtained in 30 h. This clearly indicated that the model stood valid even on large-scale. Thus, the statistical optimization strategy led to a 3.5-fold increase in the yield of succinic acid. This is the first report on the use of FCCCD to improve succinic acid production from E. coli.


Asunto(s)
Algoritmos , Reactores Biológicos/microbiología , Técnicas de Cultivo de Célula/métodos , Escherichia coli/metabolismo , Modelos Biológicos , Ácido Succínico/metabolismo , Anaerobiosis/fisiología , Análisis de Varianza , Interpretación Estadística de Datos , Fermentación/fisiología , Modelos Estadísticos , Proyectos Piloto , Control de Calidad , Ácido Succínico/aislamiento & purificación
11.
J Biochem Biophys Methods ; 63(1): 24-32, 2005 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-15892975

RESUMEN

Succinic acid, an intermediate of tricarboxylic acid cycle, is produced and accumulated by anaerobic microorganisms. The long-standing interest in the production of this organic acid is because it is a key compound in producing more than 30 commercially important products. The detection of succinic acid is generally carried out by gas chromatography (GC), enzymatic assays, ion-exclusion chromatography (IEC) or by high performance liquid chromatography (HPLC). However, these methods are time consuming, require sophisticated instrumentation and are expensive. In the present investigation we are reporting two rapid, cost effective screening methods for the detection of this important organic acid. These methods can be utilized to screen a large number of microbes producing succinic acid in a very short span of time.


Asunto(s)
Bacterias/metabolismo , Hongos/metabolismo , Ácido Succínico/metabolismo , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Colorantes Fluorescentes , Reproducibilidad de los Resultados , Resorcinoles , Ácido Succínico/química , Ácido Succínico/aislamiento & purificación , Ácidos Sulfúricos
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