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1.
Appl Biochem Biotechnol ; 193(1): 33-51, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32808248

RESUMEN

Fungal enzymes are widely used in technological processes and have some interesting features to be applied in a variety of biosynthetic courses. Here, free and substrate-immobilised lipases from Fusarium verticillioides P24 were obtained by solid-state fermentation using wheat bran as substrate and fungal carrier. Based on their hydrolytic and transesterification activities, the lipases were characterised as pH-dependent in both reactions, with higher substrate conversion in an alkaline environment. Thermally, the lipases performed well from 30 to 45 °C, being more stable in mild conditions. Organic solvents significantly influenced the lipase selectivity using different vegetable oils as fatty acid source. Omega(ω)-3 production in n-hexane achieved 45% using canola oil, against ≈ 18% in cyclohexane. However, ω-6 production was preferably produced for both solvents using linseed oil with significant alterations in the yield (≈ 79% and 49% for n-hexane and cyclohexane, respectively). Moreover, the greatest enzyme selectivity for ω-6 led us to suppose a lipase preference for the Sn1 position of the triacylglycerol. Lastly, a transesterification reaction was performed, achieving 90% of ester conversion in 72 h. This study reports the characterisation and use of free and substrate-immobilised lipases from Fusarium verticillioides P24 as an economic and efficient method for the first time.


Asunto(s)
Biocatálisis , Enzimas Inmovilizadas/química , Proteínas Fúngicas/química , Fusarium/enzimología , Lipasa/química , Esterificación
2.
Trends psychiatry psychother. (Impr.) ; 42(1): 86-91, Jan.-Mar. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1099407

RESUMEN

Abstract Objectives To investigate the 5-year prevalence of patients admitted to public inpatient care units due to a mental disorder, stratifying them by age group and diagnosis, and to assess trends of admissions over this time period in Porto Alegre. Methods All admissions to the public mental health care system regulated by the city-owned electronic system Administração Geral dos Hospitais (AGHOS) were included in the analysis. The total population size was obtained by estimations of Fundação de Economia e Estatística (FEE). General information about 5-year prevalence of inpatient admissions, time-series trends e prevalence by age groups and diagnosis were presented. Results There were 32,608 admissions over the 5-year period analyzed. The overall prevalence of patients was 1.62% among the total population, 0.01% among children, 1.12% among adolescents, 2.28% among adults and 0.93% among the elderly. The most common diagnosis was drug-related, followed by mood, alcohol-related and psychotic disorders. There was a linear trend showing an increase in the number of admissions from 2013 to the midst of 2014, which dropped in 2015. Conclusions Admissions due to mental disorders are relatively common, mainly among adults and related to drug use and mood disorders. Time trends varied slightly over the 5 years. Prevalence rates in real-world settings might be useful for policymakers interested in planning the public mental health system in large Brazilian cities.


Resumo Objetivos Investigar a prevalência de 5 anos de pacientes internados no sistema público de saúde por motivo de saúde mental, estratificando-os por grupo etário e diagnóstico, e avaliar tendências temporais nas admissões nesse período em Porto Alegre. Métodos Todas as admissões no sistema público de saúde mental reguladas pelo sistema eletrônico da cidade, denominado Administração Geral dos Hospitais (AGHOS), foram incluídos na análise. A população total foi obtida a partir de estimativas da Fundação de Economia e Estatística (FEE). Informações gerais sobre a prevalência de 5 anos de admissões, tendências das séries temporais e prevalência por grupo etário e por diagnóstico foram apresentadas. Resultados Ocorreram 32.608 admissões no período de 5 anos analisado. A prevalência global de pacientes foi de 1,62% na população total, 0,01% em crianças, 1,12% em adolescentes, 2,28% em adultos e 0,93% em idosos. Os diagnósticos mais comuns foram relacionados ao uso de drogas, seguidos de transtornos de humor, relacionados ao álcool e transtornos psicóticos. Houve uma tendência linear mostrando um aumento no número de admissões de 2013 a meados de 2014, que caíram em 2015. Conclusões Admissões por transtornos mentais são relativamente comuns, principalmente entre adultos e relacionados ao uso de drogas e transtornos de humor. Tendências lineares variaram levemente nos últimos 5 anos. Estimativas de prevalência no mundo real podem ser úteis para formuladores de políticas interessados em planejar o sistema público de saúde mental em grandes cidades brasileiras.


Asunto(s)
Adolescente , Adulto , Niño , Preescolar , Humanos , Lactante , Persona de Mediana Edad , Adulto Joven , Admisión del Paciente/estadística & datos numéricos , Hospitales Públicos/estadística & datos numéricos , Trastornos Mentales/epidemiología , Brasil/epidemiología , Prevalencia , Trastornos del Humor/terapia , Trastornos del Humor/epidemiología , Trastornos Relacionados con Sustancias/terapia , Trastornos Relacionados con Sustancias/epidemiología , Pacientes Internos/estadística & datos numéricos , Trastornos Mentales/terapia
3.
Trends Psychiatry Psychother ; 42(1): 86-91, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939593

RESUMEN

OBJECTIVES: To investigate the 5-year prevalence of patients admitted to public inpatient care units due to a mental disorder, stratifying them by age group and diagnosis, and to assess trends of admissions over this time period in Porto Alegre. METHODS: All admissions to the public mental health care system regulated by the city-owned electronic system Administração Geral dos Hospitais (AGHOS) were included in the analysis. The total population size was obtained by estimations of Fundação de Economia e Estatística (FEE). General information about 5-year prevalence of inpatient admissions, time-series trends e prevalence by age groups and diagnosis were presented. RESULTS: There were 32,608 admissions over the 5-year period analyzed. The overall prevalence of patients was 1.62% among the total population, 0.01% among children, 1.12% among adolescents, 2.28% among adults and 0.93% among the elderly. The most common diagnosis was drug-related, followed by mood, alcohol-related and psychotic disorders. There was a linear trend showing an increase in the number of admissions from 2013 to the midst of 2014, which dropped in 2015. CONCLUSIONS: Admissions due to mental disorders are relatively common, mainly among adults and related to drug use and mood disorders. Time trends varied slightly over the 5 years. Prevalence rates in real-world settings might be useful for policymakers interested in planning the public mental health system in large Brazilian cities.


Asunto(s)
Hospitales Públicos/estadística & datos numéricos , Trastornos Mentales/epidemiología , Admisión del Paciente/estadística & datos numéricos , Adolescente , Adulto , Brasil/epidemiología , Niño , Preescolar , Humanos , Lactante , Pacientes Internos/estadística & datos numéricos , Trastornos Mentales/terapia , Persona de Mediana Edad , Trastornos del Humor/epidemiología , Trastornos del Humor/terapia , Prevalencia , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/terapia , Adulto Joven
4.
Molecules ; 24(19)2019 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-31597244

RESUMEN

Statistical evidence pointing to the very soft change in the ionic composition on the surface of the sugar cane bagasse is crucial to improve yields of sugars by hydrolytic saccharification. Removal of Li+ by pretreatments exposing -OH sites was the most important factor related to the increase of saccharification yields using enzyme cocktails. Steam Explosion and Microwave:H2SO4 pretreatments produced unrelated structural changes, but similar ionic distribution patterns. Both increased the saccharification yield 1.74-fold. NaOH produced structural changes related to Steam Explosion, but released surface-bounded Li+ obtaining 2.04-fold more reducing sugars than the control. In turn, the higher amounts in relative concentration and periodic structures of Li+ on the surface observed in the control or after the pretreatment with Ethanol:DMSO:Ammonium Oxalate, blocked -OH and O- available for ionic sputtering. These changes correlated to 1.90-fold decrease in saccharification yields. Li+ was an activator in solution, but its presence and distribution pattern on the substrate was prejudicial to the saccharification. Apparently, it acts as a phase-dependent modulator of enzyme activity. Therefore, no correlations were found between structural changes and the efficiency of the enzymatic cocktail used. However, there were correlations between the Li+ distribution patterns and the enzymatic activities that should to be shown.


Asunto(s)
Celulosa/química , Análisis Discriminante , Litio/química , Saccharum/química , Fenómenos Químicos , Hidrólisis , Iones/química , Microscopía de Fuerza Atómica , Propiedades de Superficie
5.
Bioresour Technol ; 252: 143-149, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29316500

RESUMEN

Extents of adsorption of cellulolytic enzymes on lignin, derived from sugarcane bagasse, were an inverse function of incubation temperature and varied with type of lignin extraction. At 45 °C, lignin derived from acid hydrolyzed liquid hot water pretreated bagasse completely adsorbed cellulolytic enzymes from Trichoderma reesei within 90 min. Lignin derived from enzyme hydrolyzed liquid hot water pretreated bagasse adsorbed only 60% of T. reesei endoglucanase, exoglucanase and ß-glucosidase activities. ß-Glucosidase from Aspergillus niger was not adsorbed. At 30 °C, adsorption of all of the enzymes was minimal and enzyme hydrolysis at 30 °C approached that at 45 °C after 168 h. Hence, temperature provided an approach to decrease loss of enzyme activity by reducing enzyme adsorption on lignin. This helps to explain why simultaneous saccharification and fermentation (SSF) and consolidated bioprocessing (CBP), both carried out at 30-32 °C, could offer viable options for mitigating lignin-derived inhibition effects.


Asunto(s)
Celulasa , Celulosa , Saccharum , Adsorción , Hidrólisis , Lignina , Temperatura , Trichoderma , beta-Glucosidasa
6.
Bioresour Technol ; 224: 733-737, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27889354

RESUMEN

Modifications in sugarcane bagasse (SCB) from ozonolysis (O) NaOH (B) and ultrasound (U) (OBU) treatment for cellulosic ethanol production by enzymatic hydrolysis, were evaluated when increasing the exposure time of SCB to ozone. The lignin, cellulose, and hemicellulose after treatment were quantified: lignin removal and a consequent increase in cellulose content were shown using an infrared spectroscopic technique (ATR-FTIR) and chemical characterization. X-ray diffraction analysis (XRD) proved that OBU treatment does not affect the crystalline cellulose portion and electron microscopy techniques established that the fiber region most affected by the OBU treatment was the secondary cell wall, where the greatest lignin content is located. For OBU-60 treatment the lignin content was reduced and consequently there was a significant increase in cellulose content. After enzymatic hydrolysis, this pretreated SCB released 418mgglucose/g, corresponding to six times more than untreated SCB and a yield of 93% of the cellulose available.


Asunto(s)
Biotecnología/métodos , Ozono/química , Saccharum/química , Pared Celular/química , Celulasa/química , Celulosa/química , Hidrólisis , Lignina/química , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Polisacáridos/química , Saccharum/citología , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
7.
Bioresour Technol ; 219: 773-777, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27578061

RESUMEN

The present work aimed to study the effect of the pretreatment of sugarcane bagasse and straw with microwave irradiation in aqueous and acid glycerol solutions on their chemical composition, fiber structure and the efficiency of subsequent enzymatic hydrolysis. Thermogravimetric analysis showed that the pretreatment acted mainly on the lignin and hemicellulose fractions of the bagasse, whereas, in the straw, lesser structural and chemical changes were observed. The images from transmission electron microscopy (TEM) revealed that treating bagasse and straw with acid glycerol solution loosened the cell walls and there was a breakdown in the pit membrane. The treated material was submitted to hydrolysis for 72h and higher yields of reducing sugars were observed compared to the untreated material (250.9mg/g from straw and 197.4mg/g from bagasse). TEM images after hydrolysis confirmed the possible points of access of the enzymes to the secondary cell wall region of the pretreated biomass.


Asunto(s)
Biotecnología/métodos , Celulosa/química , Enzimas/química , Saccharum/química , Biomasa , Pared Celular/química , Celulosa/metabolismo , Enzimas/metabolismo , Glicerol/química , Hidrólisis , Lignina/química , Lignina/metabolismo , Microscopía Electrónica de Transmisión , Microondas , Monosacáridos/química , Monosacáridos/metabolismo , Brotes de la Planta/química , Brotes de la Planta/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo , Saccharum/citología , Saccharum/metabolismo , Soluciones/química , Termogravimetría
8.
Bioresour Technol ; 218: 69-76, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27347800

RESUMEN

Sugarcane bagasse (SCB) was treated in three stages using ozone oxidation (O), washing in an alkaline medium (B) and ultrasonic irradiation (U). The impact of each pretreatment stage on the physical structure of the SCB was evaluated by its chemical composition, using an infrared technique (FTIR-ATR), and using thermogravimetric analysis (TGA/DTG). The pretreatment sequence O, B, U provided a significant reduction of lignin and hemicellulose, which was confirmed by changes in the absorption bands corresponding to these compounds, when observed using infrared. Thermogravimetric analysis confirmed an increased thermal stability in the treated sample due to the removal of hemicellulose and extractives during the pretreatment. This pretreatment released 391mg glucose/g from treated SCB after the enzymatic hydrolysis, corresponding to a yield of 94% of the cellulose available.


Asunto(s)
Celulasa/metabolismo , Celulosa , Ozono/farmacología , Saccharum , Sonicación , Celulasa/química , Celulosa/efectos de la radiación , Glucosa/metabolismo , Ondas de Choque de Alta Energía , Hidrólisis/efectos de los fármacos , Hidrólisis/efectos de la radiación , Lignina/análisis , Lignina/metabolismo , Oxidación-Reducción/efectos de los fármacos , Ozono/análisis , Saccharum/efectos de los fármacos , Saccharum/metabolismo , Saccharum/efectos de la radiación , Sonicación/métodos , Ultrasonido
9.
Bioresour Technol ; 185: 316-23, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25795445

RESUMEN

A pretreatment with microwave irradiation was applied to enhance enzyme hydrolysis of corn straw and rice husk immersed in water, aqueous glycerol or alkaline glycerol. Native and pretreated solids underwent enzyme hydrolysis using the extract obtained from the fermentation of Myceliophthora heterothallica, comparing its efficiency with that of the commercial cellulose cocktail Celluclast®. The highest saccharification yields, for both corn straw and rice husk, were attained when biomass was pretreated in alkaline glycerol, method that has not been previously reported in literature. Moreover, FTIR, TG and SEM analysis revealed a more significant modification in the structure of corn straw subjected to this pretreatment. Highest global yields were attained with the crude enzyme extract, which might be the result of its content in a great variety of hydrolytic enzymes, as revealed zymogram analysis. Moreover, its hydrolysis efficiency can be improved by its supplementation with commercial ß-glucosidase.


Asunto(s)
Ascomicetos/metabolismo , Carbohidratos/química , Fermentación , Glicerol/química , Lignina/química , Microondas , Biomasa , Biotecnología , Celulasa/metabolismo , Celulosa/química , Hidrólisis , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , beta-Glucosidasa/metabolismo
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