Alginate purification

Dusseault, J., Tam, S. K., Menard, M., Polizu, S., Jourdan, G., Yahia, L., et al. (2006). Evaluation of alginate purification methods effect on polyphenol, endotoxin and protein contamination. Journal of Biomedical Materials Research, Part A, 76, 243—251. 

Bovine serum albumin (BSA), fraction V, B-lactoglobulin, gum arabic, and alginic acid, low viscosity, were purchased from Sigma Chemical Co. (St. Louis, MO). The proteins were used without further purification. Aqueous solutions of gum arabic and alginic acid were filtered successively through cellulosic membrane filters of 5.0 fan and 0.45 fan pore size to remove insoluble particulate matter. The filtrate was frozen and lyophilized prior to use. 

Immobilized cells are also used in biotechnology in the production of protein molecules. For example, entrapped hybridoma cells have been used for the production of monoclonal antibodies which are secreted into the microcapsules. This allows for easier collection of the antibodies compared to growing the hybridoma cells directly in the culture medium. The microcapsules are easily separated from the culture medium and broken to collect the antibodies. Isolation of the antibodies from the culture medium involves numerous purification steps, and product is lost during each of these steps to an extent which depends on the efficiency of the process. Live vaccines have been encapsulated. For example. Bacillus Calmette Guerin has been encapsulated in an alginate polylysine-alginate system. 

Without further purification, water may be unsuitable for certain pharmaceutical applications for example, the presence of calcium in water affects the viscosity and gel strength of algins and pectin dispersions, while the use of potable water affects the clarity and quality of cough mixtures, and the stability of antibiotic liquid preparations. 

The immobilized XAD-4 resins in E-carrageenan and calcium alginate are non-toxic to the microbial culture. Thus, the adsorbents can be added directly to the fermenting broth. Both fermentation and product separation can occur at the same time (8). As shown in Table 1, the immobilized resin can be recovered from the fermentation broth. The cycloheximide product can be recovered from the immobilized beads by extraction using butyl acetate. The immobilized beads maintained its mechanical strength through the extraction. In some cases, the purity of the cycloheximide in the solvent is close to 95-100% pure. Very limited additional purification such as crystallization may be used to make the final pure product. 

The GMP activity that is used in alginate synthesis is associated with the algA gene product, which also catalyzes the PMI reaction. The first indications that AlgA is bifunctional came when the protein was purified. The isomerase and pyrophosphorylase activities co-purified, and their activities remained in constant ratio throughout the purification. Brief treatment with chymotrypsin cleaved approximately 1 kDa from the C-terminus of AlgA the remaining protein retained GDP-pyrophosphorylase activity, but the phosphoman-nose isomerase activity was lost. ... 

Gomez, C.G., Perez Eambrecht, M.V., Lozano, J.E., Rinaudo, M., Villar, M.A. Influence of extraction-purification conditions on final properties of alginates obtained from brown algae (Macrocystis pyrifera). Int. J. Biol. Macromol. 44, 365-371 (2009)... 

Scheme 7.1 Schematic representation of extraction-purification of sodium alginate from brown algae...

Schneider (1997) used the combination of an ultrafiltration pre-concentration step with precipitation for purification. Alginate could be quantitatively reclaimed from ethanol, methanol and acetone CMC and carboxymethylated guar gum to 50-85% the reclamation of synthetic thickeners was less successful. Water-soluble dyes were extracted with water/solvent mixtures (40/60) and disperse dyes with acetone, giving excellent results in the case of alginates, less in the case of all... 

Kinoshita, S., Y. Kumoi, A. Ohshima, T. Yoshida and N. Kasai, Isolation of a alginate degrading organism and purification of its alginate lyase. Journal of fermentation and bioengineering, 72 (1991) 74-78. 

Many naturally occurring materials and industrial residue from different processes can be snitable adsorbents due to their cost effectiveness (Bailey et al. 1999). A low cost adsorbent is normally the material which is abundantly available, no further or very little purification is required or is a waste or by product of some industrial process (Bailey et al. 1999). A lot of research is going on to study the properties of these adsorbents. Some common adsorbents used in water treatment to adsorb heavy metal ions are zeolites, alginates and activated charcoal. 

In the presence of the dye-stuff a preliminary purification by solvent extraction is necessary before applying the alginic acid isolation of the alkaloids described above. 

For spectrophotometric determination this preparation cannot be purified sufficiently by alginic acid alone, because of the high proportion of interfering materials, which also occasionally prevent the repeated use of the cplumn. Preliminary purification by treatment with alumina is satisfactory. ... 

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