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41.
This study describes pentachlophenol (PCP) sorption in nylon fiber in which Rhizopus oryzae ENHE was immobilized to remove the chemical compound. The experimental sorption data were analyzed using the Langmuir, Freundlich, and Redlich-Peterson isotherm models using non-linear error functions to fit the experimental data to the three models. Results showed that the isotherm obtained from the data fitted the three models used. However, the g parameter from Redlich-Peterson model showed that the isotherm obtained approaches the Freundlich model. This support reached the sorption equilibrium concentration at 3mg PCPg(-1)nylon. To study PCP removal capability by R. oryzae ENHE and to eliminate the error caused by PCP sorbed by the nylon fiber during its quantification, nylon fiber at PCP equilibrium sorption concentration was used to immobilize R. oryzae ENHE. It was found that this fungus grew within nylon fiber cubes in presence or not of PCP, even when PCP caused growth inhibition. Maximum biomass accumulated into nylon cubes without PCP was of 32 mg biomass g(-1)nylon and into nylon cubes at PCP equilibrium concentration was of 18 mg g(-1)nylon. The results showed that R. oryzae ENHE immobilized into nylon fiber removed 88.6% and 92% of PCP in cultures with 12.5 and 25 mg PCPL(-1), as initial concentration, respectively. This is the first work to report that a zygomycete, such as R. oryzae ENHE, immobilized into nylon fiber kept its potential to remove PCP.  相似文献   
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In the present work, on the basis of literature data, correlations for ultrasound-assisted dissolution of lignin and hemicelluloses from lignocellulosic raw material were defined in Aspen Plus® as function of applied power and duration of the ultrasound treatment. The dissolution yield of these biomass components was represented against the applied acoustic energy, taking into account the volume of solvent–solid treated in each case, making possible the calculation of ultrasonic power consumption in a simulated biorefinery pretreatment process. The proposed ultrasound-assisted process was techno-economically evaluated in terms of process yield and utility requirements. Furthermore, energy and exergy analyses were performed in order to assess the profitability of the simulated ultrasound-assisted biomass fractionation processes.  相似文献   
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Mamey sapote (Pouteria sapota (Jacq.) H. E. Moore & Stearn) is a tropical species from the Sapotaceae family native to Mexico and Central America. Its tree produces an edible climacteric fruit, whose weight can range from 250 to 900 g. The flesh is soft, comprises about 78% of the fruit, and has high sugars to acidity ratio, which gives it a sweet taste when ripe. Because of current public interest to consume products that promote health, the aim of the work was to characterize soluble phenolic content and antioxidant activity in mamey sapote fruits from Chiapas, Mexico, at different maturity stages. Storage at 12 (± 1) °C was conducted for 18 d. When fruits ripened firmness flesh varied, in average, from 41.8 to 3.0 N, soluble solids content from 17.7 to 28.1 ºBrix, hue angle from 56.4 to 46.3º, and lightness from 67.3 to 42.0. Phenolic content was affected by ripening since average values of 2563 and 234 ??g/g were found in unripe and consumption maturities, respectively. In a soluble phenolics extract from flesh, gallic acid (GA), gallocatechin-3-gallate (G3G), epicatechin (ECT), and catechin (C) were found, being the latter the most abundant compound, which increased with ripening from 9.9 to 113.1 ??g/g, while GA, G3G, and ECT had average values of 4.7, 11.9, and 5.8 ??g/g, respectively, without significant variation. Antioxidant activity, expressed through the IC50 parameter, remained practically unchanged and showed an average value of 12.9 ??g/mL. Based on phenolic composition the mamey sapote fruit may constitute a good source of antioxidant compounds.  相似文献   
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Pompe disease (PD) is a rare disorder caused by mutations in the acid alpha-glucosidase (GAA) gene. Most gene therapies (GT) partially rely on the cross-correction of unmodified cells through the uptake of the GAA enzyme secreted by corrected cells. In the present study, we generated isogenic murine GAA-KO cell lines resembling severe mutations from Pompe patients. All of the generated GAA-KO cells lacked GAA activity and presented an increased autophagy and increased glycogen content by means of myotube differentiation as well as the downregulation of mannose 6-phosphate receptors (CI-MPRs), validating them as models for PD. Additionally, different chimeric murine GAA proteins (IFG, IFLG and 2G) were designed with the aim to improve their therapeutic activity. Phenotypic rescue analyses using lentiviral vectors point to IFG chimera as the best candidate in restoring GAA activity, normalising the autophagic marker p62 and surface levels of CI-MPRs. Interestingly, in vivo administration of liver-directed AAVs expressing the chimeras further confirmed the good behaviour of IFG, achieving cross-correction in heart tissue. In summary, we generated different isogenic murine muscle cell lines mimicking the severe PD phenotype, as well as validating their applicability as preclinical models in order to reduce animal experimentation.  相似文献   
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Modifications of dietary fibre in beetroot during autoclaving have been evaluated by different methods: acid detergent (raw=1.45%; processed=1.17%) and neutral detergent (raw=2.30%; processed=2.00%), the enzymatic-gravimetric method of Asp (raw=3.35%; processed=3.34%), HPLC (raw=1.42%; processed=1.60%) and 3,5-dimethylphenol (raw=0.36; processed=0.28%). The correlation between different methodologies was studied. Autoclaving was carried out at 121°C under pressure for 15 min. Variance analysis indicated that quantitative variations originating in the thermic treatment were not statistically significant (P>0.05).  相似文献   
50.
An efficient protocol for the synthesis of homopropargylic alcohols using propargylic carbonates as pronucleophiles is reported. The reaction is based on a combination of transition metal (palladium) and radical chemistry (titanium). The reaction takes place with an excellent regioselectivity and tolerates a great degree of substitution of the starting propargylic carbonate, thus being an interesting tool in the context of synthetic organic chemistry.  相似文献   
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