Extract the plant material with 96% ethanol. If the tissue is rich in lipids (e.g. seeds), it may be necessary to remove them with acetone and with ethyl ether, discarding the organic fractions. Extract neutral water-soluble polysaccharides with 1% NaCl solution or with boiling water. Recover these polysaccharides from the solution by pouring the extracts into several volumes of 96% ethanol, where they precipitate. Extract the pectins from the residue with 0.5% ammonium oxalate and subsequently precipitate them from the solution by acidification and pouring into 96% alcohol. Remove lignin by extraction with 1% NaCl at 70°C for 1 hour. For tissues rich in lignin, the extraction procedure must be repeated several times. Alternatively, delignification can be achieved by extraction with chloramines-T (sodium p-toluene-sulfonchloramide) and ethanolamine. These extracts are discarded and the residue is washed and dried.
The hemicelluloses are removed from the dried residue by keeping with 7-12% NaOH at room temperature for 24 hours. This last procedure must be repeated to obtain thorough separation of the hemicelluloses. Then, the hemicelluloses are recovered by acidification of the alkaline extracts with acetic acid and precipitation with ethanol. The remaining material is washed and dried, and this is the cellulose fraction.
Gums and mucilages can be purified by dissolving in water and precipitating with ethanol. Then, they are collected and dried.
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