As an alternative to extraction with scCO2, accelerated solvent extraction ASE (Dionex™ ASE™ 350) offers high efficiency and flexibility with regards to extraction conditions (temperature, solvents, extraction time), allowing not just extracting the sum of lipophilic compounds, but additionally fractionating them. ASE has almost no restrictions with regard to the organic solvents or solvent mixtures used as extractants.
Accelerated solvent extraction offers unique opportunities for the extraction of solubilizable components from insoluble natural matrices, such as bark, pulp, lignin, wood, and lignocellulosic materials in general, with the starting material being efficiently depleted of the extractives but otherwise left chemically unchanged.
Very lipophilic components, such as triglycerides, sterol esters, or waxes, to medium polarity compounds, such as sterols, triterpenoids, fatty acids, resin acids, mono and diglycerides, to hydrophilic molecules, such as lignans, flavonoids, phenolics and other polyphenols, can be extracted according to the choice of solvent or solvent mixture and the setting of other extraction conditions. The pressurized extraction vessel (up to 100 bar) allows the extraction at temperatures higher than the normal-pressure boiling points of the extraction solvents, maximizing solubility and minimizing the extraction time.
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