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1.
Data Brief ; 22: 227-233, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30581932

RESUMO

Burial of infectious and potentially infectious livestock and poultry animals is the most common response to an emergency situation. The data set summarizes 22-week-long experiment that simulates the environment found within conventional burial trenches for emergency disposal of animal carcasses, worldwide, sometimes with a topical application of quicklime as it is required in the Republic of Korea. This data set shows the rarely presented evidence of the extremely slow decay of animal carcasses. Besides visual evidence of no visible breakdown of carcass material, i.e., carcass (or carcass quarters and coarse cuts) still resembled the initial material at the end of the study, we present data characterizing the process. Specifically, temporal variations of digestate quality (pH, ammonia, volatile fatty acids), biogas production, and the persistence of odorous volatile organic compounds are summarized. The data provide important evidence of undesirable, slow progression of the digestion process. The evidence of failure to achieve practical endpoints with the anaerobic digestion provides the impetus for seeking alternative, improved methods of disposal that will be feasible in emergency context, such as aerated burial concept (Koziel et al., 2018 [1]).

2.
Food Chem ; 232: 799-807, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490143

RESUMO

A passive sampling method, using retracted solid-phase microextraction (SPME) - gas chromatography-mass spectrometry and time-weighted averaging, was developed and validated for tracking marker volatile organic compounds (VOCs) emitted during aerobic digestion of biohazardous animal tissue. The retracted SPME configuration protects the fragile fiber from buffeting by the process gas stream, and it requires less equipment and is potentially more biosecure than conventional active sampling methods. VOC concentrations predicted via a model based on Fick's first law of diffusion were within 6.6-12.3% of experimentally controlled values after accounting for VOC adsorption to the SPME fiber housing. Method detection limits for five marker VOCs ranged from 0.70 to 8.44ppbv and were statistically equivalent (p>0.05) to those for active sorbent-tube-based sampling. The sampling time of 30min and fiber retraction of 5mm were found to be optimal for the tissue digestion process.


Assuntos
Biomarcadores/análise , Aves Domésticas , Animais , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Compostos Orgânicos Voláteis
3.
Bioresour Technol ; 101(22): 8698-705, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20624677

RESUMO

The effect of mild alkali and steam pretreatments on fungal saccharification and sequential simultaneous-saccharification and fermentation (SSF) of corn fiber to ethanol was studied. The corn fiber was pretreated with: (i) 2% NaOH (w/w) at 30 degrees C for 2h and (ii) steaming at 100 degrees C for 2h. Ethanol yields were 2.6g, 2.9g and 5.5g ethanol/100g of corn fiber, respectively, for Phanerochaete chrysosporium, Gloeophyllum trabeum and Trichoderma reesei saccharification and sequential SSFs. SSF with commercial cellulase enzyme - Spezyme-CP had 7.7g ethanol/100g corn fiber. Mild alkali pretreatment resulted in higher glucose yields following fungal saccharification of corn fiber. However, the ethanol yields were comparatively similar for untreated and mild alkali pretreated corn fiber. Solid-substrate fermentation of corn fiber with fungi can be improved to either eliminate or reduce the dosage of commercial cellulase enzymes during SSF.


Assuntos
Álcalis/química , Metabolismo dos Carboidratos/fisiologia , Etanol/metabolismo , Fungos/metabolismo , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/microbiologia , Zea mays/química , Zea mays/microbiologia , Fermentação/fisiologia , Solubilidade , Vapor
4.
Bioresour Technol ; 101(10): 3526-33, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20096573

RESUMO

Degradation of lignocellulosic biomass to sugars through a purely biological process is a key to sustainable biofuel production. Hydrolysis of the corn wet-milling co-product-corn fiber-to simple sugars by the brown rot fungus Gloeophyllum trabeum was studied in suspended-culture and solid-state fermentations. Suspended-culture experiments were not effective in producing harvestable sugars from the corn fiber. The fungus consumed sugars released by fungal extracellular enzymes. Solid-state fermentation demonstrated up to 40% fiber degradation within 9days. Enzyme activity assays on solid-state fermentation filtrates confirmed the involvement of starch- and cellulose-degrading enzymes. To reduce fungal consumption of sugars and to accelerate enzyme activity, 2- and 3-d solid-state fermentation biomasses (fiber and fungus) were submerged in buffer and incubated at 37 degrees C without shaking. This anaerobic incubation converted up to almost 11% of the corn fiber into harvestable reducing sugars. Sugars released by G. trabeum were fermented to a maximum yield of 3.3g ethanol/100g fiber. This is the first report, to our knowledge, of G. trabeum fermenting sugar to ethanol. The addition of Saccharomyces cerevisiae as a co-culture led to more rapid fermentation to a maximum yield of 4.0g ethanol/100g fiber. The findings demonstrate the potential for this simple fungal process, requiring no pretreatment of the corn fiber, to produce more ethanol by hydrolyzing and fermenting carbohydrates in this lignocellulosic co-product.


Assuntos
Basidiomycota/metabolismo , Metabolismo dos Carboidratos , Etanol/metabolismo , Zea mays , Basidiomycota/enzimologia , Biomassa , Fermentação
5.
J Chromatogr A ; 1216(2): 281-7, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-19081100

RESUMO

There has been considerable public interest and a growing number of scientific studies linking certain phenolic compounds in grapes and wines, particularly trans-resveratrol (trans-3,5,4'-trihydroxystilbene, TRA), to human health benefits. Typical TRA concentrations in wine are very low. It is a polar compound with very low volatility, which makes it difficult to extract and to separate on a gas chromatography (GC) column without derivatization. In this study, a new method for trace analysis of TRA was developed using solid-phase microextraction (SPME) with on-fiber silylation derivatization. Multidimensional GC equipped with a heartcut valve and cryogenic focusing was coupled with a mass-selective detector and used for improved separations and analysis. The effects of SPME fiber selection, extraction time, temperature, and desorption time were investigated. The derivatization conditions, time/temperature and the volume of derivatization reagent were also optimized. The calibration curve was linear over the concentration range from 10 ng L(-1) to 5 mg L(-1), with a correlation coefficient of 0.9996. The average recovery of TRA in red wine was 83.6+/-5.6%. The method detection limit (MDL) for TRA in ethanol:water (12.5:87.5, v/v) solution in this study was 7.08 ng L(-1) whereas the MDL for TRA in pure water was 2.85 ng L(-1). The new method was used to test the TRA content in six selected Iowa red wine samples. Measured concentrations varied from 12.72 to 851.9 microg L(-1).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Estilbenos/análise , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Modelos Lineares , Reprodutibilidade dos Testes , Resveratrol , Sensibilidade e Especificidade , Estereoisomerismo , Temperatura , Fatores de Tempo
6.
Water Res ; 39(20): 5119-25, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16289281

RESUMO

Ozone has been investigated for its potential to remove marine dinoflagellate algae from ships' ballast water. Dinoflagellate algae, Amphidinium sp. isolated from the Great Barrier Reef, Townsville, Australia were used as indicators since these produce a type of cyst that is difficult to inactivate, but are relatively easy to culture. The ozonation experiments have demonstrated a high ozone demand for inactivation of the algal cultures, which increases as the culture ages. The main ozone demand in seawater is due to its reaction with bromide to form bromine compounds. The non-bromide ozone demand has been estimated by measuring the residuals produced after various doses of ozone. The Amphidinium sp. show an unexpected response to both ozonation and bromination, with an instantaneous inactivation of the organisms for all doses that produced an oxidant residual in the seawater, followed by an effect of the disinfection residual. The standard design procedure of comparing Ct will not be effective for predicting the response of the organism to varying dose, C, and contact time, t, and a plot of ozone produced oxidant residual against organism inactivation for various contact times is proposed for design purposes. High doses of ozone (5-11 mg/L) and up to 6h of residual contact were required for a 4-log inactivation of the Amphidinium sp. Ozonation is likely to be a difficult technology to implement for organisms with this ozone requirement in combination with characteristics of ballast tanks, which contain areas of sediments high in detritus and areas of corrosion.


Assuntos
Dinoflagellida/efeitos dos fármacos , Ozônio/toxicidade , Purificação da Água/métodos , Animais , Bromo , Desinfecção , Água do Mar , Navios , Fatores de Tempo , Poluentes da Água
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