Glucosamine VOLUME

To 40 g. of dry chitin in a 500-ml. beaker is added 200 ml. of concentrated hydrochloric acid (c.p., sp. gr. 1.18), and the mixture is heated on a boiling water bath for 2.5 hours with continuous mechanical agitation. At the end of this time solution is complete, and 200 ml. of water and 4 g. of Norite are added. The beaker is transferred to a hot plate, and the solution is maintained at a temperature of about 60° and is stirred continuously during the process of decolorization. After an hour the solution is filtered through a layer of a filter aid such as Filter-Cel. The filtrate is usually a pale straw color however, if an excessive color persists, the decolorization may be repeated until the solution becomes almost colorless. The filtrate is concentrated under diminished pressure at 50° until the volume of the solution is 10-15 ml. The white crystals of glucosamine hydrochloride are... 

The chemistry and biological activities of lipid A are reviewed in earlier chapters of this volume. As noted there, the components of the lipid A complexes from Salmonella species and j5. coli are derivatives of a disaccharide comprised of two D-glucosamine units linked B,l->-6. The disaccharide is substituted at positions 1 and 4 by phosphate functions and on the amino nitrogens by B-hydroxymyristoyl groups. A variable number (up to 5) of ester-linked fatty acyl residues is also present. In the simplest components the phosphates are present as monoester groups. 

Vial Volume of 0.5 /xmol/ml Glucosamine Standard (/d) Volume of Dilute Carbohydrate Solution (pi) Volume of Water (/d)... 

Taking into account the dilution of the original unknown carbohydrate sample and the volume of this diluted sample present in vials 6 to 8, determine the concentration of glucosamine in the original unknown carbohydrate solution. Express the concentration in units of micromoles per milliliter and milligrams per milliliter. 

Fig. 3-109. Separation of amino sugars with and without post-column addition of NaOH. - Separator column CarboPac PA-1 eluent 0.01 mol/L NaOH flow rate 1 mL/min detection and injection volume see Fig. 3-105 solute concentrations 30 ppm galactosamine (1), 60 ppm glucosamine (2), and 30 ppm N-acetylgalactosamine (3).

Compared with the support materials, the final catalysts of the Ag-IW-XX line (table 2) uniformly show lower values for surface area and pore volumes, whereas the pore diameters remained almost constant. This can be explained by a simple blocking of part of the supports mesocavities by silver particles. The extent of area and volume reduction differs among the catdysts and is maximum with glucosamine hydrochloride and glucose, respectively. However, no consistent correlation can be deduced. 

PIA is a (3-1,6 linked A-acetyl glucosamine homopolymer. Deacetylated PIA is cationic because of the free amino groups with a theoretical pK = 6.9 that become protonated at neutral or acidic pH. Acetylated PIA is insoluble at neutral pH, especially after precipitation from the culture filtrate with ethanol, or with increasing concentration of PIA after reducing the volume by ultrafiltration devices. 

Fig. 3-169. Low level determination of monosaccharides using CarboPac PA20. - Eluant 12 mmol/L NaOH flow rate 0.5 mL/min detection pulsed amperomet7 on a gold working electrode injection volume lOpL solute concentrations 200 fmol each of fucose (1), galactosamine (2), glucosamine (3), galactose (4), glucose (5), and mannose (6).

Fig. 3-175. Gradient elution of phos-pho lated mono- and di-saccharides. -Separator column CarboPac PAl eluant (A) 0.1 mol/L NaOH, (B) 0.1 mol/L NaOH -i-1 mol/L NaOAc gradient linear, 10% B to 20% B in 20 min, then to 50% B in 10 min flow rate 1 mL/min detection pulsed amperomet7 on a Au working electrode injection volume 50 pL solute concentrations 22.6 mg/L a-D-galactosamine-l-P (1), 9 mg/L a-D-glucosamine-l-P (2), 35 mg/L each of...

The third synthetic methodology of D-glucosamine transformation into surfactants was applied by Kida et al. [ 119], who reacted this sugar amine with long-chain aldehydes. The obtained surfactants may be regarded as chemo-degradable (cleavable) surfactants (this volume. Chapter 10). They are stable... 

Dissolve 0.300 g of D(+)glucosamine hydrochloride in water and make the volume to exactly 100 ml in a measuring flask. 

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