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Effects were compared for three low-cost pretreatment methods (dilute acid, alkali, and steam explosion) relative to the effectiveness of environmentally friendly enzymatic hydrolysis and ethanol fermentation of aspen, birch, and ...
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Effects were compared for three low-cost pretreatment methods (dilute acid, alkali, and steam explosion) relative to the effectiveness of environmentally friendly enzymatic hydrolysis and ethanol fermentation of aspen, birch, and oak chips. The highest monomeric sugar yield was achieved with the alkali pretreatment of the aspen chips (22 g/L of glucose and 6 g/L of xylose). Additionally, the concentration of lignocellulose degradation products formed during this pretreatment was relatively low, and so the hydrolysis and fermentation efficiencies were 80% and 85%, respectively. The application of dilute acid pretreatment led to lower yield of enzymatic hydrolysis in comparison with alkali pretreatment, resulting in 41% to 62% of theoretical yield for aspen and birch chips, respectively. Increasing the NaOH concentration led to an increase in the monomeric sugar yield, and consequently increased the hydrolysis and fermentation yields. By contrast, increasing the acid concentration resulted in a higher sugar yield, and the fermentation efficiency decreased. The applied steam explosion conditions resulted in the formation of 6.8 to 15.4 g glucose/L, with hydrolysis yield in the range 34 to 42% of theoretical. The most susceptible for pretreatment and enzymatic hydrolysis was found to be aspen biomass.
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In this study, emulsion gel beads for loading quercetin were prepared through an emulsification/gelation process using whey protein isolate (WPI) and pectin. Emulsion gel beads’ properties were investigated by different pectin co...
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In this study, emulsion gel beads for loading quercetin were prepared through an emulsification/gelation process using whey protein isolate (WPI) and pectin. Emulsion gel beads’ properties were investigated by different pectin content. Additionally, the physicochemical properties, morphology and quercetin release properties from beads were explored. Firstly, electrical characteristics and the rheology of bead-forming solutions were measured, revealing that all systems had strong negative charge and exhibited shear-thinning behavior. The textural results demonstrated that the properties of emulsion gel beads were improved with increasing the content of pectin. It was also confirmed that crosslinking was formed between WPI emulsion and pectin by Fourier Transform Infrared (FTIR) analysis and thermogravimetric analysis (TGA). In addition, the shape of the beads was spherical or ellipses with smooth surfaces and they had a tight gel network of internal structures, which was visualized by using electron microscopy (SEM). Finally, the amount of quercetin released in vitro was gradually decreased with increasing pectin content; it was as low as 0.59%. These results revealed that WPI emulsion–pectin gel beads might be an effective delivery system for quercetin as a colon target and are worth exploring further.
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This study constructed a beta-galactosidase (beta-gal) liposome model instead of bacterial cells to optimize spray-drying protectants and parameters. The screened protectant combination consisted of 35 g/L monosodium glutamate, 50...
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This study constructed a beta-galactosidase (beta-gal) liposome model instead of bacterial cells to optimize spray-drying protectants and parameters. The screened protectant combination consisted of 35 g/L monosodium glutamate, 50 g/L sucrose, and 35 g/L maltodextrin. The optimal parameters for spray drying were 130 degrees C inlet air temperature, 7.5 mL/min feed flow rate, and 150 mL optimal protectant combination. The viability of the five lactic acid bacteria strains spray-dried with the optimized protectant and parameters was over 50%.Lactobacillus helveticusstrain LH-9's mechanism of resistance to spray-dry treatment was investigated in the presence of the optimal protectant combination.
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This study's previous work showed that the carcinogen and mutagen benzo(a)pyrene (BaP) can be adsorbed by Lactobacillus cells in vitro. However, in vivo BaP detoxification by lactic acid bacteria has not yet been investigated. The...
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This study's previous work showed that the carcinogen and mutagen benzo(a)pyrene (BaP) can be adsorbed by Lactobacillus cells in vitro. However, in vivo BaP detoxification by lactic acid bacteria has not yet been investigated. The present study evaluates the effects of orally administered Lactobacillus plantarum CICC 23121 in BaP-treated mice. Oral administration of 50 mg kg(-1) BaP perturbed the intestinal microflora, caused Proteobacteria to predominate, and severely damaged DNA. However, oral administration of 5 x 10(10) CFU mL(-1) CICC 23121 in BaP-treated mice enhances fecal BaP excretion from 181.70 +/- 1.04 mu g/(g center dot h) to 271.47 +/- 11.71 mu g/(g center dot h) after 6 h. Fecal BaP excretion reaches up to 280.66 +/- 22.97 mu g/(g center dot h) after the first 4 days of orally administered CICC 23121 and decreased to 94.31 +/- 2.64 mu g/(g center dot h) by day 11. Intestinal microbiota are restored and Firmicutes predominates. CICC 23121 alleviates BaP-induced DNA damage and reduces tail length from 56.37 +/- 5.31 to 39.69 +/- 4.27 mu m. Therefore, oral CICC23121 consumption is a promising strategy for reducing BaP toxicity in mice. To the best of our knowledge, this report is the first report to demonstrate in vivo that Lactobacillus cells can detoxify BaP.
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Continuous catalytic condensation of crude distillates or rectified bioethanol into butanol and other fuel bicomponents was performed over 8-20%Ni/Al2O3 catalysts. Experiments were conducted using solid catalysts in a flow reactor...
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Continuous catalytic condensation of crude distillates or rectified bioethanol into butanol and other fuel bicomponents was performed over 8-20%Ni/Al2O3 catalysts. Experiments were conducted using solid catalysts in a flow reactor under supercritical conditions. The most promising nickel catalyst yielded almost 13% butanol after a single passage of the raw spirit or rectified ethanol at 330 degrees C, 120 atm. The butanol content in the liquid products was further increased to 31.4% (v/v) by the additional step of rectification and recycling of the low-boiling fraction through a catalytic reactor. The use of a two-zone reactor filled with different catalytic systems (I. 8%Ni/Al2O3; II. 5%Pd-8%Fe/Al2O3) allowed the system to operate under milder pressure (80 atm) and temperature (290 degrees C) conditions, while maintaining approximately 13% (v/v) of the butanol content in the reaction mixture. The results of the studies suggest the possibility of using continuous-flow technologies for the industrial-scale catalytic condensation of bioethanol into butanol and higher homologues, which are valuable fuel biocomponents. (C) 2015 Elsevier Ltd. All rights reserved.
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Several samples of materials of potential interest as component in building materials, especially in sulfur polymer concrete (SPC) composites, were checked for their radium content and radon exhalation rate. However, the radiation...
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Several samples of materials of potential interest as component in building materials, especially in sulfur polymer concrete (SPC) composites, were checked for their radium content and radon exhalation rate. However, the radiation hazard strongly depends on radon exhalation rate from these materials, the influence of SPC composition was investigated concerning radon exhalation and emanation from the composite matrix. The accumulation method using RAD7 device was used for specific exhalation rate determinations. The activity concentrations of Ra-226 in the man-made tiles were in the range of 6.1-593 Bq.kg(-1). The Rn-222 exhalation rates from these materials were in the range of 103 mBq.m(-2) h(-1) -9.22 Bq.m(-2) h(-1), whereas from the SPC composites from 40.2 to 438 mBq.m(-2) h(-1). SPC manufacture technology and sulfur polymers applied for composites preparation allow for nearly 50-fold decrease of radon emanation coefficient. Different factors (e.g.: physical form of additives or polymer composition and its weight fraction) affecting radon emanation coefficient and its exhalation rate from examined raw materials and composites were discussed. Using a standard room parameters, the Rn-222 concentration resulting from its exhalation from the walls and annual internal doses were estimated indicating for satisfactory results even for raw materials of the highest Ra-226 concentration. (C) 2018 The Authors. Published by Elsevier Ltd.
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Sugar beet juice was sterilized by ozonation under lab. conditions by bubbling O-3 through the tested solns. with registration of O-3 concns. on the inlet and outlet of the reactor with periodical detn. of color in the tested soln...
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Sugar beet juice was sterilized by ozonation under lab. conditions by bubbling O-3 through the tested solns. with registration of O-3 concns. on the inlet and outlet of the reactor with periodical detn. of color in the tested soln. and its surface tension. The juice fermentation with fodder yeast showed a higher reproduction of the yeast when compared to the test using a juice sterilized in a conventional manner.
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The possibility of using sugar beet pulp to produce yeast biomass was evaluated in this study. Viscozyme and Ultraflo Max preparations were used for hydrolysis, which was performed on a semi-industrial scale. Out of 250 kg of wet ...
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The possibility of using sugar beet pulp to produce yeast biomass was evaluated in this study. Viscozyme and Ultraflo Max preparations were used for hydrolysis, which was performed on a semi-industrial scale. Out of 250 kg of wet beet pulp, 375 dm(3) of hydrolysate was obtained. After being enriched with mineral salts (N, P, K, Mg), the medium was inoculated with Trichosporon cutaneum LOCK 0254, Candida tropicalis LOCK 0007 Pichia stipitis LOCK 0047, Candida guilliermondii ATCC 6260 and Saccharomyces cerevisiae LOCK 0132 yeast strains.
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