Sub‐and Supercritical CO₂‐Extraction of Hypericum perforatum L.

Abstract

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).

Positive correlations between hypericin and putative precursors detected in the quantitative secondary metabolite spectrum of Hypericum

“…More recently, a series of detailed studies on the secondary metabolite contents of different Hypericum species were performed that included a number of species from Serbia (Smelcerovic et al, 2004(Smelcerovic et al, , 2006a(Smelcerovic et al, ,b, 2007Gudzic et al, 2007;Glisic et al, 2008), Macedonia (Smelcerovic and Spiteller, 2006), Tenerife (Bonkanka et al, 2008), and Turkey Smelcerovic et al, 2008). Furthermore, studies have been made on the very important and commercially recognized Hypericum perforatum L. from India (Buter et al, 1998;Verma et al, 2008).…”

EXTRACTION OF HYPERFORIN AND HYPERICIN FROM ST. JOHN'S WORT (HYPERICUM PERFORATUM L.) WITH DIFFERENT SOLVENTS

“…The hyperforin contents were 2.29% and 2.56% by mass of dry, respectively. In another study the extraction of Hipericum perforatum L. by liquid carbon dioxide (pressure [p] 8 MPa, temperature [T] 288K) gave almost the same extract yield (1%, w/w) as by supercritical carbon dioxide (p = 10 MPa, T = 313 K) (Smelcerovic et al. 2004).…”

Use of compressed fluids for sample preparation: Food applications

“…In all the cases the extract could be directly analyzed using liquid chromatography with no other [44], or from different herbaceous materials like oregano [15], rosemary [45], laurel (bay leaves) [46], cinnamon [47], cumin [48], horsetail (Equisetum giganteum L.) [49] or St John's wort (Hypericum sp.) [50,51]. Essential oils are not only valuable as aroma but also some of them are highly appreciated as functional ingredients with different activity (antioxidant (oregano), antimicrobial (rosemary), antidepressant (St. John's wort).…”