Carvone and limonene in caraway fruits (Carum carvi L.) analyzed by supercritical carbon dioxide extraction-gas chromatography

Abstract

Dried fruits of caraway (Carum carvi L.) were analyzed with on-line supercritical fluid extractiongas chromatography using supercritical carbon dioxide at 50 °C and 9.7 MPa of pressure. The solutes were cryogenically collected onto a DB-1 capillary GC column, and the effluent was vented out. The compounds were subsequently eluted from the collection column with helium onto the head of the analytical DB-5 capillary column and cryofocused with liquid nitrogen. The volatiles were detected by flame ionization detection and identified by mass spectrometry. The rapid analytical procedure for quality assessment purposes was optimized for limonene and carvone, and their contents in the fruits were analyzed by using internal standards. Analyses of carvone in cultivar Polaris carried out by supercritical extraction and hydrodistillation gave the same result, 2.7 g/100 g, but limonene contents determined were 1.8 and 1.3 g/100 g, respectively. The carvone content of Finnish caraway fruits of four origins cultivated in 1991 varied between 2.2 and 2.9 g/100 g of dried fruits and the ratio of carvone to limonene varied from 1.7 to 2.4 in various fruit samples.

Evaluation of caraway essential oil from different production areas of Serbia

“…The overall quality of fruits is considered to correlate with the content of essential oil and its carvone/limonene (C/L) ratio: the higher the ratio, the better the quality (Kallio et al 1994). As it can be seen from our findings, the C/L ratio was 0.58 on average (Table 2).…”

“…It seems that there is a correlation between assimilate availability and essential oil formation. According to other researchers (Puschmann et al 1992;Kallio et al 1994;Sedláková et al 2003a) C/L ratio varies from 0.90 to 2.74.…”

“…In our experiment, the main components were carvone and limonene, whose mixture constituted from 97.69 to 98.62% of total oil composition. According to other researchers (Kallio et al 1994;Ahroet al 2001;Sedláková et al 2003a;Seidler-Lozykowska et al 2010), the percentage of carvone and limonene in essential oil ranges from 93.2 to 99.8%. Apart from monoterpenes, the essential oil contains sesquiterpenes (β-bourbonene, β-elemene, trans-caryophyllene, trans-muurola-4(14), 5-diene and caryophyllene oxide).…”

“…Some authors (Kallio et al 1994;Sedláková et al 2003a;Laribi et al 2010) postulate that there are more components in caraway essential oil.…”

Determination of essential oil content in caraway (Carum carvi L.) species by means of supercritical fluid extraction

“…In SFE, carbon dioxide is used predominantly (Engelhardt and Gross 1988, Bounoshita et al 1993, Kallio et al 1994) because of its low critical temperature (31°C) and low critical pressure (7.38 MPa), negligible toxicity, incombustibility and low reactivity. Its polarity and extraction power are close to n-hexane.…”