Sucrose, solution preparation

Sucrose Solution Prepare a suitable volume of a 10% w/v solution of sucrose in water. 

Alternative Step D Reduction with a Reductate — Sucrose (1 kg) is dissolved in water (9 liters) in a 20-liter bottle equipped with a gas trap. Baker s yeast Saccharomyces cerevisiae, 1 kg) is made into a paste with water (1 liter) and added to the sucrose solution with stirring. After lively evolution of gas begins (within 1 to 3 hours), 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole hydrogen maleate [1.35 mols, prepared by reaction of the 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole with an equimolar quantity of maleic acid in tetrahydrofuran]. The mixture is allowed to stand until fermentation subsides, after which the bottle is kept in a 32°C incubator until all fermentation has ended (in approximately 1 to 3 days). The yeast is filtered off with addition of diatomaceous earth and the filtrate is evaporated to dryness to give S-3-mor-pholino-4/3-tert-butylamino-2-hydroxypropoxy)-1,2,5-thiadiazole, MP 195° to 198°C (as hydrogen maleate), according to U.S. Patent 3,619,370. 

Calculate the vapor pressure of water at 20.°C in a solution prepared by dissolving 10.00 g of the nonelectrolyte sucrose, C12H2201, in 100.0 g of water. 

Multivesicular Liposomes Kim and his colleages described a method for the preparation of cell size liposomes with high encapsulation efficiency the so-called multivesicular liposomes (Kim et al., 1983). The lipid phase consists of a combination of amphiphatic lipids and a small amount of triglycerides (triolein or trioctanoin) dissolved in chloroform-diethyl ether (1 1). The aqueous phase is slowly added to the organic phase and after vigorous shaking a water-ip-lipid emulsion is formed (Fig. 2A-B). Via a narrow Pasteur pipet the emulsion is subsequently added to a sucrose solution. 

The most active extracts were obtained8 from L. mesenteroides cultures containing sucrose extracts prepared from L. mesenteroides organisms repeatedly transferred through D-glucose broth were of low potency.48 Active extracts in dilutions of 1 2 or 1 4 produced dextran in 5% sucrose solutions after one to two hours at 23°, and at pH 5.6 with acetate buffer demonstrable amounts of dextran were produced after twenty days with 1/10,000 dilution of the extract. Optimal yields of dextran were less than 5% based on sucrose. Small concentrations of dextran were detected by means of precipitin titrations with pneumococcus antisera Types II or XX (see page 215). 

SAQ 5.5 An aqueous solution of sucrose is prepared. It is shaken with an equal volume of pure chloroform. The two solutions do not mix. The sucrose partitions between the two solutions, and is more soluble in the water. The value of /((partition) for this water-chloroform system is 5.3. What percentage of the sucrose resides in the chloroform ... 

The refractive index also varies with the amount of substance in a mixture. Most often, refractive index is used to assess the concentration of sugar in wine, soft drinks, cough medicines and other preparations having relatively high concentrations of sucrose. Refractive index is also used to determine the concentration of alcohol in fermented products. For sucrose solutions the refractive index varies from 1.3330 (pure water) to 1.5033 when the solution contains 85% sucrose. This is an increase of approximately 0.0002 in the refractive index for each 0.1%... 

After the bath attained its equilibrium temperature, the crystallizer was charged with about 400 ml of liquid and was inserted into the bath. After about 30 minutes the system attained a constant temperature and a subcooling (difference of equilibrium temperature and constant temperature before initiation of crystaUization) was established. Introduction of the seed crystals ( ter being allowed to warm for a period of a few seconds) on the specially prepared stirrer initiated crystallization (secondary nucleation) and resulted in a change in the temperature of the crystallizer (figure 2). The temperature of the crystallizer attained an uilibrium value of a few minutes after nucleation occurred. The concentration of the sucrose solutions was measured using a refractometer (.1% accuracy). 

Prepare the sample in buffer E with a protein concentration not more than 20 mg/ml. Heat the solution to 95 °C for 2-3 min and supplement with some crystals of sucrose or a droplet of glycerol or 1/10 volume of bromophenol blue in 50% sucrose solution. 

The preparation of cell nuclei from rat liver is an example of the application of a pre-formed stepwise gradient The tissue homogenate is placed on top of a cushion of concentrated sucrose solution, and only the dense nuclei cross this cushion during centrifugation. 

Sensory Analysis. A paired comparison test was run to determine if the difference in oil droplet size in the emulsion changed the perceived intensity of the orange flavor. The coarsest emulsion (3.87 pM) and the Microfluidized sample (0.90 pM) from the third set of spray dried samples were compared. The solutions were prepared using 200 ppm flavor in a 10% (w/v) sucrose solution with 0.30% of a 50% citric acid solution added. The amount of each powder required to attain 200 ppm orange oil was calculated on the basis of percent oil in each powder (determined by Clevenger analysis). A pair of samples at approximately 10 C was given to each of 24 untrained panelists. The samples were coded with random numbers. Half the panelists were asked to taste the coarsest sample first while while the other half tasted the Microfluidized sample first. This was done to determine whether or not adaptation was a factor. The panelists were asked to indicate which sample had the most intense orange flavor. 

B 8. You have just prepared a solution by weighing 20 g of sucrose, transferring it to a 1-liter volumetric flask, and adding water to the line. Calculate the concentration of the sucrose solution in terms of mM, mg/mL, and % (wt/vol). 

Prepare solutions of 40%, 30%, and 10% sucrose (w/v) in sucrose gradient buffer. Place 500 pL of 40% sucrose solution in a 13.2-mL ultracentrifuge tube. Layer a 10%-30% sucrose gradient on top of the 40% cushion, using a gradient mixer. 

A sucrose solution was prepared by dissolving 13.5 g C12H22O11 in sufficient water to make exactly 100 mL, which was then found to have a density of 1.050 g/mL. Compute the molar concentration and the molality of the solution. 

Prepare a sucrose solution at 60%. Dissolve 12 g of sucrose in 10 ml of buffer by heating and mixing. Once the sucrose is completely dissolved, complete with buffer up to 20 ml. 

Etanercept is available as a preservative-free powder for reconstitution or as a solution in prefilled syringes. The powder should be reconstituted in bacteriostatic water, containing 0.9% benzyl alcohol, to a final concentration of etanercept of 25 mg/mL. The prefilled syringes contain 25 mg or 50 mg etanercept in a 1% sucrose solution containing sodium phosphate, sodium chloride and l-arginine. Both preparations are administered by subcutaneous injection. 

Standard Solution Prepare an aqueous solution having known concentrations of 10 mg/mL of sucrose (reference standard material is available from NIST) and 10 mg/mL of maltose (available from Sigma Chemical Co.). 

Standard Solution Add 0.15 mL of the Sample Preparation to 140 mL of the Sucrose Solution, and mix. This solution contains the equivalent of 240,000 Scoville Heat Units. 

C-D. Progress of the Reaction with Time. For the second of the following two sets of runs, prepare some 0.03 M sucrose solution by diluting 1 mL of the 0.3 M stock solution with 9 mL of distilled water. Runs in series C use the concentrated sucrose solution, and those in series D use the dilute solution. 

E. Dependence of Initial Rate on Substrate Concentration. Prepare from the 0.3 A/stock solution of sucrose, another 10 mL of 0.03 M sucrose solution. Taking care to use the sucrose solution called for in each case, proceed to the following runs—all of which are allowed to proceed for the standard time of 5.0 min except run EO, which is a zero-time blank. This set of runs will be analyzed to obtain and K. 

G-H. Dependence of the Rate on Temperature. In order to determine the temperature dependence of the enzyme-catalyzed rate, the reaction is carried out at several different temperatures, which are held constant to within 0.3°C or better. Choose from mns E a set of initial concentrations that gives an absorbance of —0.5 at room temperature after the standard assay. Convenient temperatures for these runs, denoted as runs G, are 0°C (ice bath), 12, 25, 35, and 45°C. In each case, prepare the enzyme-water-buffer mixture in the assay tube, put about 2 mL of the sucrose stock solution in another test tube, and immerse both tubes in the thermostat bath for a few minutes to achieve temperature equilibrium. Next, pipette 1.0 mL of the equilibrated sucrose solution into the assay tube and read the bath temperature. Leave the assay tube in the constant-temperature bath until, 5.0 min after the addition of the sucrose solution, the reaction is terminated by the addition of 2.0 mL of the dinitrosalicylate reagent. Then complete the assay as usual. 

Sucrose solutions are also susceptible to attack by microorganisms. In this instance, it is sufficient to use a freshly prepared solution each day. 

Solutions. A variety of comments will be given here about the preparation of the required solutions. As noted above, a new sucrose solution must be prepared each day by the student team doing the experiment. The enzyme solution must be prepared and tested in advance, presumably by the teaching staff. Other solutions may be made available to the students or be prepared by them, depending upon the policy of the instmctor. A complete list of all solutions is given in the Apparatus section. 

The enzyme was prepared from rat and human cerebral cortex. Cortical samples were homogenized in a sucrose solution, and the homogenate was used directly as the enzyme source. 

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