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Phase separation and drop size distributions in dilute Na-caseinate/Na-alginate mixtures has been investigated using simultaneously two different measuring techniques: light scattering and image analysis. It has been found that even at very low concentrations of either polymer, where according to literature data the mixture should be homogenous, two phases can be observed. This phase separation was detected by both techniques and in each case, the drop size distributions measured by each of them were in good agreement.  相似文献   
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The partition and purification of α-amylase from a culture supernatant of Aspergillus oryzae CBS 819.72 was made in aqueous two-phase system (ATPS). According to bibliography and preliminary studies, the factors polyethylene glycol (PEG) molecular weight (MPEG) and concentration (CPEG), buffer type (BU) and concentration (CBU), temperature (T), salt nature (SALT) and concentration (CSALT), bioligand (BL) and concentration (CBL) and pH were investigated using a Plackett–Burman design to identify the factors affecting separation. Taking into consideration a simultaneous increase in enzyme recovery (RY) and purification factor (PF), the best performance of the system was obtained at 4 °C and pH 6 using PEG 8000 g/mol, citrate buffer, KCl and sucrose. Experimental Box–Behnken design together with the Response Surface Methodology (RSM) have been used to find optimum CPEG, CCitrate and CSALT. Quadratic models were predicted for PF and RY in the top phase and a better compromise between these two parameters can be found by superimposing the contour plots of PF and RY for 8% citrate. A region in the experimental space can be defined where the purification factor is always higher than 3 with yields exceeding 65%.  相似文献   
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In this study a suitable alcohol/salt aqueous two‐phase (ATP) system was selected for the recovery of 1,3‐propandiol (1,3‐PD) from fermentation broth. From the different alcohol/salt systems studied the ethanol and dipotassium hydrogen phosphate ATP system appeared to be favorable. To examine the potential of this ATP system the partition coefficient of 1,3‐PD in synthetic solutions was first optimized with the response surface methodology. The parameters studied were concentrations of ethanol (21.99–38.81% w/w), dipotassium hydrogen phosphate (14.99–31.81% w/w) and 1,3‐PD (6.36–73.64 g/L). The optimum conditions were found to be 35.39% w/w for ethanol, 28.40% w/w for dipotassium hydrogen phosphate and 73.6 g/L for 1,3‐PD. Under these conditions the maximum partition coefficient of 1,3‐PD and the extraction yield were determined as 23.14 and 97.82%, respectively. The optimum extraction conditions were then used to guide the recovery of 1,3‐PD from a real fermentation broth. The partition coefficient and extraction yield of 1,3‐PD reached 20.28–97.20% in this case, respectively. A favorable partition of the organic acids lactate, acetate and butyrate in the bottom phase was also achieved. We have also studied the removal of cells and macromolecules from the broth. Removal ratio of cells and proteins were 96.47 and 93.05%, respectively. Thus, the ethanol/dipotassium hydrogen phosphate ATP system appears to be an interesting alternative or can be used as one useful step in the downstream processing of 1,3‐PD from fermentation broth.  相似文献   
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An integrated fermentation–separation process for the production of 1,3-propanediol (1,3-PD) was investigated. Aqueous two-phase system (ATPS) not only recovered 97.9% of 1,3-PD, but simultaneously also removed 99.1% cells, 81.9% proteins, 75.5% organic acids, and 78.7% water. Furthermore, after extraction the bottom phase of ATPS was used to adjust the pH of the culture during fermentation, leading to 16% and 126% increases in the concentrations of 1,3-PD and lactic acid, and dramatic decreases in the concentration of acetic acid and formic acid. The total mass conversion yield of three main products (1,3-PD, 2,3-butanediol, and lactic acid) from glycerol reached 81.6%. The salt-enriched phase could also be used to absorb carbon dioxide (CO2), resulting in 94% recovery for carbonate. Finally, process simulation using the program PRO/II showed the use of ATPS reduced 75.1% of the energy expenditure and 89.0% of CO2 emissions.  相似文献   
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PurposeThis study aims to perform comprehensive longitudinal immune factor analysis of aqueous humor in relation to the aqueous CMV viral load and systemic CD4 counts during treatment of patients with co-infection of HIV and CMVR.MethodsAqueous humor samples were collected from 17 HIV-positive patients with CMVR scheduled to undergo weekly intravitreal ganciclovir therapy as part of the prospective CMV Retinitis Intravitreal Ganciclovir Singapore Study (CRIGSS) over the course of 1 year. Full data across all the 4 time points was obtained and analyzed for CMV DNA viral load, 41 cytokine and chemokine factors using real-time PCR with the FlexMAP 3D (Luminex®) platform and assessed using the Milliplex Human Cytokine® kit.ResultsThe following immune factors (Spearman correlation coefficient r value in parenthesis, p < 0.05) showed strong correlation with CMV DNA load in the aqueous - MCP-1 (0.80, IFN-g (0.83), IP-10 (0.82), IL-8 (0.81), fractalkine (0.73), RANTES (0.68) - while the following showed moderate correlation - PDGF-AA (0.58), Flt-3L (0.59) and G-CSF (0.53). Only PDGF-AA revealed a statistically significant negative correlation with serum CD4 levels (r = −0.74).ConclusionImmune factors that correlate with intraocular CMV DNA load are identified. They are indicative of a Th1 and monocyte-macrophage mediated response, and exhibit a decreasing trend longitudinally through the course of treatment. These factors may be an important new consideration in individualizing the treatment of patients with CMVR.  相似文献   
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This research was designed to evaluate the CNS depressant, anxiolytic, and analgesic action of aqueous and ethanol extract of Ganoderma applanatum, a valuable medicinal fungus used in multiple disorders belongs to Ganodermataceae family. Two extracts of G. applanatum were prepared using distilled water and ethanol as solvents and named AEGA and EEGA. Open field method, rotarod method, tail suspension method, and hole cross method were utilized for the CNS depressant action. In contrast, elevated plus-maze test and hole board method were utilized for the anxiolytic action. For determining the analgesic potential, acetic acid-induced writhing test, hot plate method, and tail immersion test were used. Besides, molecular docking has been implemented by using Discovery studio 2020, UCSF Chimera and PyRx autodock vina. At both doses (200 and 400 mg/kg) of AEGA and EEGA showed significant CNS depressant effect (p < 0.05 to 0.001) against all four tests used for CNS depressant activity. Both doses of AEGA and EEGA exhibited important anxiolytic activity effect (p < 0.05 to 0.001)against the EPM and hole board test. Both doses of AEGA and EEGA also exhibited a potential analgesic effect (p < 0.05 to 0.001) against all three tests used for analgesic action. In addition, in the molecular docking the compounds obtained the scores of ?5.2 to ?12.8 kcal/mol. Ganoapplanin, sphaeropsidin D and cytosporone C showed the best binding affinity to the selected recptors. It can be concluded that AEGA and EEGA have potential CNS depressant, anxiolytic, and analgesic action, which can be used as a natural antidepressant, anxiolytic, and analgesic source.  相似文献   
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Summary Oleic acid methyl esters production was studied in aqueous medium (aw>0.9) in the presence of an enzymatic extract fromCandida deformans and methanol. The yields of the reaction were 82% and 58% when the subtrates were oleic acid and triolein respectively.  相似文献   
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