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1.
Food Sci. Technol (SBCTA, Impr.) ; 38(1): 13-18, Jan.-Mar. 2018. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-892236

RESUMO

Abstract In the present study, the software Aspen Plus® was used to analyse two different systems for CO2 recycle in a SFE process for extraction of more polar compounds using ethanol as co-solvent, the most common co-solvent used due to its environment-friendly nature. The extraction process of β-ecdysone from Brazilian ginseng roots was considered as example in the computational simulations. The first CO2 recycle system, named Recycle A, considered the compression of the CO2 separated in the second flash to the recycle pressure assumed at the first flash tank, its cooling to 25 °C and recirculation, while the second recycle system, named Recycle B, considered the cooling and pumping of the CO2 separated in the second flash, its heating to 25 °C and recirculation. The best techno-economic condition to operate the recycling step would be using Recycle A at 40 bar and 30 °C considering a stand-alone SFE process; and using Recycle B at 40 bar and 40 °C, considering this process in close proximity of a hypothetical sugarcane biorefinery. Therefore, these results suggest that the selection where would be located the SFE plant should be taken into account during the first steps of the process design.

2.
Carbohydr Polym ; 174: 1114-1120, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28821035

RESUMO

Barley and yeast ß-glucans were selected, together with lecithin, to encapsulate resveratrol by emulsification-evaporation method to develop new and safer antifungal formulations. Different emulsification techniques were used: high-shear, high pressure and high pressure and temperature emulsification. Morphology, crystallinity, encapsulation efficiency and in vitro antifungal activity against Botrytis cinerea of the different formulations were evaluated. No significant differences between each emulsification procedure in particle size (below 90nm) and in encapsulation efficiency (70-100%) were observed; only barley ß-glucan emulsions showed lower efficiency due to the formation of a gel that retained most of the active compound. A great influence of the emulsification method and the encapsulating material on the crystallinity of the particles was observed. The highest antifungal activity (up to 53% growth inhibition) was obtained by the formulations with yeast ß-glucans, indicating an enhanced absorption of encapsulated resveratrol through the cell wall of the fungus at the presence of (1-3, 1-6)-ß-glucans.


Assuntos
Emulsificantes/química , Fungicidas Industriais/química , Hordeum/química , Leveduras/química , Botrytis/efeitos dos fármacos , Composição de Medicamentos , Resveratrol , Estilbenos/química , beta-Glucanas
3.
Materials (Basel) ; 9(6)2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28773616

RESUMO

Recently, supercritical fluid extraction (SFE) has been indicated to be utilized as part of a biorefinery, rather than as a stand-alone technology, since besides extracting added value compounds selectively it has been shown to have a positive effect on the downstream processing of biomass. To this extent, this work evaluates economically the encouraging experimental results regarding the use of SFE during annatto seeds valorization. Additionally, other features were discussed such as the benefits of enhancing the bioactive compounds concentration through physical processes and of integrating the proposed annatto seeds biorefinery to a hypothetical sugarcane biorefinery, which produces its essential inputs, e.g., CO2, ethanol, heat and electricity. For this, first, different configurations were modeled and simulated using the commercial simulator Aspen Plus® to determine the mass and energy balances. Next, each configuration was economically assessed using MATLAB. SFE proved to be decisive to the economic feasibility of the proposed annatto seeds-sugarcane biorefinery concept. SFE pretreatment associated with sequential fine particles separation process enabled higher bixin-rich extract production using low-pressure solvent extraction method employing ethanol, meanwhile tocotrienols-rich extract is obtained as a first product. Nevertheless, the economic evaluation showed that increasing tocotrienols-rich extract production has a more pronounced positive impact on the economic viability of the concept.

4.
Food Chem ; 159: 361-6, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24767067

RESUMO

Bioactive compounds of wine making by-products are of interest in food, cosmetics and pharmaceutical industries. Extraction of antioxidants under mild conditions is time-consuming, giving ground to the development of intensification processes where the operation at high temperature may deteriorate extract quality. This study examined thermal degradation of grape marc and its filtered extract (80, 100 and 150°C). The decrease in anthocyanin content was modelled under non-isothermal conditions by first order kinetics, using the Arrhenius equation. Simulated degradation under isothermal heating showed that the grape marc is more sensitive by one order of magnitude to heat than the filtered extract. This tendency was also confirmed by analyses of the total phenolic content and antioxidant activity. It is suggested that an optimal combination of temperature, treatment time and also raw material environment could be found in process intensification.


Assuntos
Extratos Vegetais/química , Polifenóis/química , Vitis/química , Antocianinas/química , Antioxidantes/química , Temperatura Alta , Cinética , Resíduos/análise , Vinho/análise
5.
Carbohydr Res ; 349: 33-8, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22226473

RESUMO

An increasing interest in biomass as a renewable feedstock for the chemical industry has risen over the last decades, and glucose, the monomer unit of cellulose, has been widely studied as a source material to produce value-added products such as carboxylic acids, mainly gluconic and formic. In this work, the non-catalysed wet oxidation of glucose using hydrogen peroxide has been analysed, obtaining molar yields to gluconic and formic acids up to 15% and 64%, respectively. Glucose conversion was generally between 40 and 50%, reaching over 80% under the highest temperature (200°C). An appropriate choice of temperature can tune product distribution as well as reaction rates. The interaction of the wet oxidation with an electrolytic reaction was also analysed.


Assuntos
Eletrólise , Glucose/química , Peróxido de Hidrogênio/química , Temperatura Ambiente , Formiatos/síntese química , Formiatos/química , Gluconatos/síntese química , Gluconatos/química , Estrutura Molecular , Oxirredução , Molhabilidade
6.
Bioresour Technol ; 102(23): 10849-54, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21993329

RESUMO

In this study, microwave treatment is analyzed as a way to accelerate the hydrolysis in anaerobic digestion of municipal wastewater sludge. The influence of the absorbed energy, power and athermal microwave effect on organic matter solubilization and biogas production has been studied. In addition, a novel method that considers the absorbed energy in the microwave system is proposed, in order to obtain comparable experimental results. The absorbed energy is calculated from an energy balance. The highest solubilization was achieved using 0.54 kJ/ml at 1000 W, where an increment of 7.1% was observed in methane production, compared to the untreated sample. Using a higher energy value (0.83 kJ/ml), methane production further increased (to 15.4%), but solubilization decreased. No power influence was found when 0.54 kJ/ml was applied at 1000, 600 and 440 W. Microwave heating was compared to conventional heating in two different experimental setups, providing similar methane yields in all cases.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Esgotos/análise , Purificação da Água/métodos , Absorção , Bactérias Anaeróbias , Análise da Demanda Biológica de Oxigênio , Desenho de Equipamento , Gases , Temperatura Alta , Hidrólise , Metano/química , Micro-Ondas , Temperatura Ambiente , Eliminação de Resíduos Líquidos/métodos , Água/química
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