Sub‐and Supercritical CO 2 ‐Extraction of Hypericum perforatum L

• Published in: Chemical engineering & technology Vol. 27; no. 12; pp. 1327 - 1329
• Main Authors: Smelcerovic, A., Lepojevic, Z., Djordjevic, S.
• Format: Journal Article
• Language: English
• Published: 01-12-2004
• ISSN: 0930-7516; 1521-4125
• DOI: 10.1002/ceat.200402053

The extraction of
Hypericum perforatum
L. by liquid carbon dioxide (p = 80 bar, t = 15 °C) gave almost the same extract yield (1 %, w/w) as by supercritical (p = 100 bar, t = 40 °C) carbon dioxide, containing the same percentages of essential oil (about 6.4 %, w/w). The increase of the extract yield at higher pressure (250 to 350 bar) is due to the increase of extragent density, i.e., solubility. By increasing the grinding degree of the drug, a higher extract yield is obtained in the supercritical range under high pressure. GC‐MS analysis of the extract composition showed that the non‐terpene compounds have the highest contribution. The oil content in the drug, determined by steam distillation, was 0.058 %, w/w. The oil content in the extracts, calculated for the drug, was significantly higher (1.2 to 1.9 times).
Plants of the genus
Hypericum
have been used as traditional medicinal plants from which antifungal, antibiotic, antiviral, and anticancer compounds have been isolated. In this paper, the
H. perforatum
L. extraction by liquid and supercritical carbon dioxide extraction was investigated, and the extract yield was monitored by total extract and essential oil content in the extract. The extraction by liquid carbon dioxide gave almost the same extract yield as by supercritical carbon dioxide, containing the same percentages of essential oil. By increasing the grinding degree of the drug, a higher extract yield is obtained in the supercritical range under high pressure.