Gangliosides extraction from tissues

Gangliosides extracted from bovine brain tissue (Cronassial, Sygen) have been widely used in Western Europe and South America for several neurological disorders. 

FIGURE 3. Scans of absorbance at 580 nm and radioactivity of thin-layer chromatograms of gangliosides extracted from NAL/N (control) and SVS AL/N cells grown in the presence of N-acetyl-[ H]mannanosamine in the tissue culture medium. Reproduced with permission from Brady and Mora, 1970. 

Preparation Of Gangliosides. The pooled tissues were homogenized in 7 volumes of cold acetone to remove neutral lipids and water. Gangliosides were extracted from the acetone-dried powder with 3 volumes of chloroform/... 

The GM2 ganglioside (14) is an example of a carbohydrate antigen, specific for melanoma, sarcoma and kidney carcinoma. It could suit the purpose of an immuno therapy with monoclonal antibodies. In previous examinations the used GM2 was extracted from human and animal tissues. In this, one ran the risk of biological contamination of the GM2, which could influence the results of an examination. For this reason R. R. Schmidt et al. developed a total synthesis of the GM2 ganglioside to sustain sufficient substance for further immunological examinations without faking artifacts. ... 

Burg, J., Banerjee, A., and Sandhoff, K., Activating proteins for ganglioside GM2 degradation by P-hexosaminidase isozymes in tissue extracts from different species. Biol. Chem. Hoppe-Seyler. 366, 887-891 (1985). 

In order to extract lipids from tissues, it is necessary to find solvents which will not only dissolve the lipids readily but will overcome the interactions between the lipids and the tissue matrix. Various solvents or solvent combinations have been suggested as extractants for lipids, and currently some interest is being shown in isopropanol-hexane (2 3 by volume), because its toxicity is relatively low [355,743], but it does not yet appear to have been tested with a sufficiently wide range of tissues. It does not extract gangliosides quantitatively. Most lipid anaiysts use chloroform-methanol (2 1 by volume), with the endogenous water in the tissue as a ternary component of the system, to extract iipids from animal, plant and bacterial tissues. Usually, the tissue is homogenized in the presence of both soivents, but better results may be obtained if the tissue is first extracted with methanol alone before the chloroform is added to the mixture. With difficult samples, more than one extraction may be needed, and with lyophilised tissues, it may be necessary to re-hydrate prior to carrying out the extraction. The... 

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