10.2.5 Fractionation
Crude extract obtained from enrichment of solutions extracted through solvents
from marine organism samples is strongly colored, and while some ingredients that
are not dissolved by solvents are captured by filtration, other components of the
organism are present, including various soluble salts, non-polar lipids, and carbohydrates. Fractionation must be performed to remove impurities before separating
out the active ingredients in this raw extract.
With fractionation, two solvents with very different specific gravities are mixed
together, resulting in the solvents splitting into two layers according to specific
gravity. When extract is dissolved by these two solvents, it does so according to its
affinity to each. In terms of sequence, fractionation proceeds from non-polar to
polar solvents. Fractions are enriched through filtering after the removal of moisture
with anhydrous sodium sulfate (Fig. 10.4).
10.2.6 Separating and Refining Substances
Careful planning of solvent conditions is required during the substance separation
and refinement process. Through the aforementioned extraction and fractionation
processes, a large portion of impurities are removed, leaving a mixture of substances with similar properties. Separation and refinement are more difficult than
extraction and fractionation and require advanced isolation techniques.
Fig. 10.4 Sequence and examples of solvents used in fractionation
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Crude extract obtained from enrichment of solutions extracted through solvents
from marine organism samples is strongly colored, and while some ingredients that
are not dissolved by solvents are captured by filtration, other components of the
organism are present, including various soluble salts, non-polar lipids, and carbohydrates. Fractionation must be performed to remove impurities before separating
out the active ingredients in this raw extract.
With fractionation, two solvents with very different specific gravities are mixed
together, resulting in the solvents splitting into two layers according to specific
gravity. When extract is dissolved by these two solvents, it does so according to its
affinity to each. In terms of sequence, fractionation proceeds from non-polar to
polar solvents. Fractions are enriched through filtering after the removal of moisture
with anhydrous sodium sulfate (Fig. 10.4).
10.2.6 Separating and Refining Substances
Careful planning of solvent conditions is required during the substance separation
and refinement process. Through the aforementioned extraction and fractionation
processes, a large portion of impurities are removed, leaving a mixture of substances with similar properties. Separation and refinement are more difficult than
extraction and fractionation and require advanced isolation techniques.
Fig. 10.4 Sequence and examples of solvents used in fractionation
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