Supercritical fluid extraction of borage (Borago officinalis L.) seeds with pure CO2 and its mixture with caprylic acid methyl ester

The influence of different pressures of CO2 and the addition of caprylic acid methyl ester as an entrainer was studied for the extraction process of borage seed. The increase of CO2 pressure from 100 to 350 bar resulted in the increase in extract yield from 0.14 to 24.29% (w/w) while the changes in the extract composition were not so considerable. The highest solubility of pure caprylic acid methyl ester in dense CO2 was determined at 100 and 300 bar (approximately 1 g of ester in 1 g of CO2). The addition of this entrainer increased the yield of pure extract up to 47.8 times at 100 bar, 2.4 times at 200 and 300 bar. Due to the high solubility of caprylic acid methyl ester at the lower (100 bar) pressure it is easy to separate the entrainer, which constituted only 4.22% of the total borage seed extract. (C) 2002 Elsevier Science B.V. All rights reserved

Comparison of oil from Nigella damascena seed recovered by pressing, conventional solvent extraction and carbon dioxide extraction

Nigella damascena seeds were extracted by cold press, in a Soxhlet apparatus and with CO2 The yield obtained with liquid CO2 was only 10.57%. EtOH (1%) increased the yield by 50%. CO2-extracts were separated into the 2 fractions. The yield in the first fraction increased 2 times by increasing the pressure from 150 to 350 bar. EtOH (1%) increased the yield 2 times at 150 bar. Linoleic acid was the major fatty acid (43.71 to 50.83%), followed by oleic (14.87 to 23.65%), stearic (15.07 to 23.24%), and palmitic (10.13 to 12.07%) acids. Elemenes (21.38% to 29.16%) were the most abundant volatile constituents, free fatty acids constituted from 35.04% to 51.18%, the majority being linoleic (32.83 to 40.58) (Range for linoleic should be 24.51 to 40.58%-see Table 3) and oleic acids (4.96 to 13.32)

Effect of fast CO2 pressure changes on the yield of lovage (Levisticum officinale Koch.) and celery (Apium graveolens L.) extracts

The effect of pressure alterations on the yield of CO2, extracts from different anatomical parts of lovage (Levisticum officinale Koch.) and celery (Apium graveolens L.) was studied. It was found that by applying frequent pressure changes in the extraction vessel it is possible to increase the rate of the isolation of CO2 soluble materials from lovage seeds and leaves, lovage and celery roots. However, after passing a sufficient amount of the supercritical solvent, the yields were similar both for constant and pulsing extraction pressures. The composition of the extracts was analyzed by gas chromatography and mass spectrometry and it was found that the phthalides were very important constituents in the extracts from all the anatomical parts of lovage, while linoleic acid was the most abundant component in the celery root extracts. (C) 2002 Elsevier Science B.V. All rights reserved