Chemical composition and antifungal activity of essential oils and supercritical CO2 extracts of Apium nodiflorum (L.) Lag.

Aerial parts of Apium nodiflorum collected in Portugal and Italy were submitted to hydrodistillation; also a supercritical fluid extract was obtained from Italian plants. The extracts were analyzed by GC and GC/MS. Both essential oils, obtained from Portuguese and Italian plants, posses high content of phenylpropanoids (51.6 vs. 70.8%); in the former, the percentage split in myristicin (29.1%) and dillapiol (22.5%), whereas in the latter, the total percentage is only of dillapiol (70.8%). The co-occurrence of myristicin and dillapiol is frequent because dillapiol results from enzymatic methoxylation of myristicin. Antimicrobial activity of phenylpropanoids has been patented, what suggest the potential of plants with high amounts of these compounds. Minimal inhibitory concentration (MIC) and minimal lethal concentration, determined according to NCCLS, were used to evaluate the antifungal activity of the essential oils against yeasts, Aspergillus species and dermatophytes. Essential oils exhibited higher antifungal activity than other Apiaceae against dermatophytes, with MIC ranging from 0.04 to 0.32 µl/ml. These results support the potential of A. nodiflorum oil in the treatment of dermatophytosis and candidosis.

Extraction of oil from wheat germ by supercritical CO2.

This study examined the supercritical fluid extraction of wheat germ oil. The effects of pressure (200-300 bar at 40 degrees C) and extraction time on the oil quality/quantity were studied. A comparison was also made between the relative qualities of material obtained by SFE and by organic solvent extraction. The extracts were analyzed for alpha-tocopherol and polyunsaturated fatty acid content. The maximum wheat germ oil yield at about 9% was obtained with supercritical carbon dioxide extraction at 300 bar, while fatty acid and alpha-tocopherol composition of the extracts was not remarkable affected by either pressure or the extraction method.

Extraction and separation of volatile and fixed oils from berries of Laurus nobilis L. by Supercritical CO2.

Isolation of volatile and fixed oils from dried berries of Laurus nobilis L. from Tunisia have been obtained by supercritical fractioned extraction with carbon dioxide. Extraction experiments were carried out at a temperature of 40 degrees C and pressures of 90 and 250 bar. The extraction step performed at 90 bar produced a volatile fraction mainly composed of (E)-beta-ocimene (20.9%), 1,8-cineole (8.8%), alpha-pinene (8.0%), beta-longipinene (7.1%), linalool acetate (4.5%), cadinene (4.7%), beta-pinene (4.2%), alpha-terpinyl acetate (3.8%) and alpha-bulnesene (3.5%). The oil yield in this step of the process was 0.9 % by weight charged. The last extraction step at 250 bar produced an odorless liquid fraction, in which a very small percentage of fragrance compounds was found, whereas triacylglycerols were dominant. The yield of this step was 15.0 % by weight. The most represented fatty acids of the whole berry fixed oil were 12:0 (27.6%), 18:1 n-9 (27.1%), 18:2 n-6 (21.4%), and 16:0 (17,1%), with the 18:1 n-9 and 18:2 n-6 unsaturated fatty acids in particular averaging 329 microg/mg of oil.

Supercritical CO2 extract of Cinnamomum zeylanicum: chemical characterization and antityrosinase activity.

The volatile oil of the bark of Cinnamomum zeylanicum was extracted by means of supercritical CO2 fluid extraction in different conditions of pressure and temperature. Its chemical composition was characterized by GC-MS analysis. Nineteen compounds, which in the supercritical extract represented >95% of the oil, were identified. (E)-Cinnamaldehyde (77.1%), (E)-beta-caryophyllene (6.0%), alpha-terpineol (4.4%), and eugenol (3.0%) were found to be the major constituents. The SFE oil of cinnamon was screened for its biological activity about the formation of melanin in vitro. The extract showed antityrosinase activity and was able to reduce the formation of insoluble flakes of melanin from tyrosine. The oil also delayed the browning effect in apple homogenate. (E)-Cinnamaldehyde and eugenol were found to be mainly responsible of this inhibition effect.

Supercritical CO2 extract from needles of Pinus nigra ssp. laricio: combined analysis by GC, GC-MS and 13C NMR.

The chemical composition of the volatile concentrate prepared by supercritical CO(2) extraction of the needles of Pinus nigra Arnold ssp. laricio Poiret from Corsica was investigated using GC (RI), GC-MS and (13)C NMR spectroscopy. The major component was by far manoyl oxide (63%), a compound of potential interest for the perfumery and pharmaceutical industries. Consequently, the supercritical fluid extract of P. nigra ssp. laricio (yield 1.60%) could be considered as a source of this diterpene.

Extraction of Lantana camara essential oil by supercritical carbon dioxide: influence of the grinding and biological activity.

The aim of this study was to produce Lantana camara essential oil by SFE and to study the effect of matrix grinding on the yield and/or composition of the extract. Experiments were carried out on grinding matrices (G) and on not grinding matrices (NG). The extracts were analyzed by GC-MS. A comparison with the oil obtained by hydrodistillation is also given. Finally, the antibacterial and antifungal activity of the various extracts has been assayed.

Comparative analysis of the oil and supercritical CO(2) extract of Artemisia arborescens L. and Helichrysum splendidum (Thunb.) Less.

Isolation of volatile concentrate from the dried leaves of Artemisia arborescens and of Helichrysum splendidum has been obtained by supercritical extraction with carbon dioxide. To obtain a pure volatile extract devoid of cuticular waxes, the extraction products were fractionated in two separators operating in series. A good extraction process was obtained operating at 90 bar and 50 degrees C in the extraction vessel, at 90 bar and at -5 degrees C in the first separator and at a pressure between 20 and 15 bar and temperatures in the range 10-20 degrees C in the second one. The composition of the volatile concentrate has been analyzed by GC/MS. The volatile concentrate of A. arborescens was found to contain: trans-thujone (13.96%), camphor (6.15%) and chamazulene (5.95%). The main constituents in the extract of H. splendidum were: germacrene D-4-ol (17.08%), germacrene D (9.04%), bicyclogermacrene (8.79%) and delta-cadinene (8.43%). A comparison with the oils obtained by hydrodistillation is also given. The differences observed between the composition of the SFE volatile concentrates and of the hydrodistilled (HD) oils were relevant. Indeed, the HD oils had a blue color whereas the volatile concentrates were pale yellow. The HD oil of H. splendidum had a blue color due to the presence of guaiazulene (0.42% vs 0%), whereas the coloration of HD oil of A. arborecens was due to the high concentration of chamazulene (26.64% vs 3.37%).

Comparative analysis of the oil and supercritical CO(2) extract of Cymbopogon citratus Stapf.

Dried and ground leaves of lemon grass (Cymbopogon citratus Stapf.) were used as a matrix for supercritical extraction of essential oil with CO(2). The objective of this study was to analyze the influence of pressure on the supercritical extraction. A series of experiments were carried out, for 360 min, at 50 degrees C and at different pressures: 90, 100, 110 and 120 bar. Extraction conditions were chosen to maximize citral content in the extract oil. The collected extracts were analysed by GC-MS and their composition was compared with that of the essential oil isolated by hydrodistillation and by steam distillation. At higher solvent density the extract aspect changes passing from a characteristic yellow essential oil to yellowish semi-solid mass because of the extraction of high molecular mass compounds. The optimum conditions for citral extraction were 90 bar and 50 degrees C, at these conditions citral represent more than 68% of the essential oil and the extraction yield was 0.65% while the yield obtained from hydrodistillation was 0.43% with a content of citral of 73%.

Isolation of Seseli bocconi Guss., subsp. praecox Gamisans (Apiaceae) volatile oil by supercritical carbon dioxide extraction.

Isolation of the volatile concentrate from dried leaves of Seseli bocconi Guss. subsp. praecox Gamisans were obtained by supercritical fluid extraction (SFE) with carbon dioxide. Leaves from different zones of Sardinia (Italy) were collected and treated. Compositions of samples were analyzed by GC-MS. The volatile concentrate of S. bocconi from Buggerru was found to contain: himachalol (16.4%), sabinene (14.8%), beta-phellandrene (8.1%), cis-sabinene hydrate (4.5%). beta-Phellandrene (29.2%), undecane (9.6%), alpha-pinene (6.1%) and beta-guaiene (5.7%) were the main constituents of the volatile extract of S. bocconi from Carloforte. The volatile concentrate of S. bocconi of Ogliastra inland, was composed chiefly by alpha-humulene (17.7%), gamma-himachalene (9.3%), beta-phellandrene (8.0) and bicyclogermacrene (7.7%). The yields of extraction were in the range (0.13-0.60%). A comparison with the hydrodistilled oil revealed in each case a remarkable difference in composition.

Chemical composition of the essential oil and supercritical CO2 extract of Commiphora myrrha (Nees) Engl. and of Acorus calamus L.

Volatile concentrates from the oleo-gum resin of Commiphora myrrha (Nees) Engl. and from the rhizomes of Acorus calamus were isolated by supercritical extraction with carbon dioxide. The volatile oil of myrrh was obtained at 9.0 MPa and 50 degrees C and at a CO2 flow of 1.5 kg/h. Acorus calamus was extracted at 9.0 MPa and 45 degrees C and at a CO2 flow of 1.6 kg/h. In both cases, an oil devoid of cuticular waxes was obtained with a single depressurization stage. The SFE myrrh oil had a yield, Y, of 3.2%. Its main components, identified and quantified by GC/MS, were furanoeudesma-1,3-diene, 34.9%; lindestrene, 12.9%; curzerene, 8.5%; and germacrone, 5.8%. The essential oils from the same starting material by hydrodistillation, HD, (Y = 2.8%) and by steam distillation, SD, (Y = 0.4%) were quite similar to the SFE extract. The main components of the SFE oil of A. calamus (Y = 3.5%) were acorenone, 13.4%; iso-acorone, 11.6%; (Z)-sesquilavandulol, 11.0%; dehydroxy isocalamendiol, 7.7%; and beta-asarone, 5.5%. The comparison with hydrodistilled (Y = 1.8%) and steam distilled (Y = 1.0%) oils revealed large differences in the content of iso-acorone and crypto-acorone.

Supercritical CO2 extract and essential oil of aerial part of Ledum palustre L.--Chemical composition and anti-inflammatory activity.

The anti-inflammatory activity of two extracts from the aerial parts of Ledum palustre has been reported. The volatile oil was obtained by supercritical fluid extraction (SFE) and the essential oil by hydrodistillation (HD). The oils were analysed by gas chromatography-mass spectrometry to monitor their composition. Both extracts shared as main compound (41.0-43.4%) ledol (23.3-26.7%) and ascaridole (15.1-4.5%). The anti-inflammatory activity was evaluated by the subcutaneous carrageenan injection-induced hind paw oedema. The treated animals received essential oil (SFE and HD), the reference group received ketoprofen or piroxicam and the control group received NaCl 0.9%. A statistical analysis was performed by the Student t-test. The results show that L. palustre essential oil enhanced a significant inhibition of oedema (50-73%) for HD oil and (52-80%) for SFE oil. These results were similar to those obtained with piroxicam (70%) and ketoprofen (55%).

Antifungal activity of extracts from Cynomorium coccineum growing wild in Sardinia island (Italy).

Cynomorium coccineum L. is a non-photosynthetic plant, spread over Mediterranean countries, amply used in traditional medicine. The aim of this study was to evaluate for the first time the antifungal activity of its extracts. The antifungal activity was evaluated using the macrodilution method against Candida spp., Cryptococcus neoformans and dermatophyte strains. The methanolic extract was very active against C. neoformans, Candida guilliermondii and Candida krusei, with minimal inhibitory concentrations (MIC) values of 0.025 mg/mL. This extract is more active than fluconazole against C. krusei H9. The influence of methanolic extract on the dimorphic transition in Candida albicans was also studied through the germ tube inhibition assay. More than 60% of filamentation was inhibited at a concentration of 1/4 MIC. These results are preliminary and further studies are needed to an eventual use of C. coccineum methanolic extract in the treatments of candidiasis and cryptococcosis.

Imazalil-cyclomaltoheptaose (beta-cyclodextrin) inclusion complex: preparation by supercritical carbon dioxide and 13C CPMAS and 1H NMR characterization.

An inclusion complex between imazalil (IMZ), a selected fungicide, and cyclomaltoheptaose (beta-cyclodextrin, betaCD) was obtained using supercritical fluid carbon dioxide. The best preparation conditions were determined, and the inclusion complex was investigated by means of 1H NMR spectroscopy in aqueous solution and 13C CPMAS NMR spectroscopy in the solid state. Information on the geometry of the betaCD/IMZ complex was obtained from ROESY spectroscopy, while the dynamics of the inclusion complex in the kilohertz range was obtained from the proton spin-lattice relaxation times in the rotating frame, T(1rho) (1H).

Comparative analysis of the oil and supercritical CO2 extract of Elettaria cardamomum (L.) Maton.

The volatile oil of Elettaria cardamomum (L.) Maton seeds was obtained by supercritical CO(2) extraction (SC-CO(2)). The effect of the extraction conditions on the yield and composition of the resulting cardamom volatile oil was examined by testing two pressure values, 9.0 and 11.0 MPa; two temperatures, 40 and 50 degrees C; two flow rate values, 0.6 and 1.2 kg/h; and two particles size values, 250-425 and >850 microm. The extraction conditions that gave the highest yield, Y (grams of extract per gram of seeds), of 5.5%, were as follows: pressure, 9.0 MPa; temperature, 40 degrees C; carbon dioxide flow, phi = 1.2 kg/h; and particles sizes in the range of 250-425 microm. Waxes, recovered as traces, were entrapped in the first separator set at 9.0 MPa and -10 degrees C. The oil was recovered in the second separator working at 1.5 MPa and 10 degrees C. The main components were as follows: alpha-terpinyl acetate, 42.3%; 1,8-cineole, 21.4%; linalyl acetate, 8.2%; limonene, 5.6%; and linalool, 5.4%. A comparison with the hydrodistilled oil, obtained at a yield of 5.0%, did not reveal any consistent difference. In contrast, the extract obtained using hexane, Y = 7.6%, showed strong composition differences. Indeed, the volatile fraction of the extract was made up mainly of the following: limonene, 36.4%; 1,8-cineole, 23.5%; terpinolene, 8.6%; and myrcene, 6.6%.

Supercritical carbon dioxide extraction and characterization of Laurus nobilis essential oil.

Supercritical carbon dioxide extraction allowed essential oil of Laurus nobilis to be obtained. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 degrees C; and carbon dioxide flow, Phi = 1.0 kg/h. Waxes were entrapped in the first separator set at 90 bar and -10 degrees C. The oil was recovered in the second separator working at 15 bar and 10 degrees C. The main components were 1,8-cineole (22.8%), linalool (12.5%), alpha-terpinyl acetate (11.4%), and methyleugenol (8.1%). Comparison with the hydrodistilled oil did not reveal any significant difference. Collection of samples at different extraction times during supercritical extraction allowed the change of the oil composition to be monitored. Lighter compounds such as hydrocarbon and oxygenated monoterpenes were extracted in shorter times than the heavier hydrocarbon and oxygenated sesquiterpenes.

13C-CPMAS and 1H-NMR study of the inclusion complexes of beta-cyclodextrin with carvacrol, thymol, and eugenol prepared in supercritical carbon dioxide.

Beta-cyclodextrin (beta-CD) inclusion complexes with carvacrol (1), thymol (2), and eugenol (3) (components of essential oils of vegetable origin) were prepared by the supercritical CO2 technique, and their structural characterization was achieved by means of 1H-NMR in aqueous solution and 13C-CPMAS NMR in the solid state. Evidence of the formation of the inclusion complexes for all the examined systems was obtained by 1H-NMR in solution, while 2D-ROESY-NMR experiments were used to investigate the geometry of inclusion. In addition, the dynamics of these inclusion complexes in the kHz timescale was investigated by analysis of the 1H and 13C spin-lattice relaxation times in the rotating frame.

Supercritical CO2 extraction of volatile oils from Sardinian Foeniculum vulgare ssp. vulgare (Apiaceae): chemical composition and biological activity.

This article reports the results on the composition and antifungal effect of volatile extracts obtained from the aerial parts of Sardinian wild fennel (Foeniculum vulgare Mill.), by supercritical fluid extraction (SFE) and by hydrodistillation (HD). The extracts were analysed by gas chromatography-mass spectrometry for qualitative composition and gas chromatography-flame ionisation detector to establish the percentage of constituents. The main components were fenchone (7.1% vs. 8.8%), estragole (34.9% vs. 42.6%) and (E)-anethole (24.6% vs. 43.4%) in the SFE and HD extract, respectively. Minimum inhibitory concentrations (MICs) were measured according to the reference Clinical and Laboratory Standards Institute (CLSI) broth macrodilution protocols. Minimum lethal concentrations were determined by subsequent subculturing of the same cell suspensions in solid medium. The essential oil was more active against Candida albicans, whereas the supercritical fluid extract possesses higher activity against Candida guillermondii and Cryptococcus neoformans, with MIC values of 0.32 µL/mL.

Antiulcerogenic and antibacterial activities of Apium graveolens essential oil and extract.

This study investigates the antiulcerogenic and antibacterial activities of Apium graveolens extracts. The antiulcerogenic activity was evaluated in rats by the HCl/EtOH method. Inhibition of gastric lesions by A. graveolens extracts was dose-dependent for both aerial part (53-76%) and seeds (51-95%). The methanolic extract as well as the aqueous extracts used at 300 mg kg(-1) dose exhibited a highly significant inhibition of gastric lesions (91% and 95%, respectively) which was similar to that induced by omeprazole (94%). Essential oil and aqueous extract prepared from the aerial parts of A. graveolens were tested to determine their antibacterial activity using the paper disc-diffusion method, the minimal inhibitory concentration and the minimal bactericidal concentration. Essential oil of A. graveolens was strongly inhibitory against Escherichia coli and moderately inhibitory against Pseudomonas aeruginosa and Staphylococcus aureus. The chemical composition of the volatile oil was investigated by gas chromatography analysis. The major components identified were ß-pinene, camphene, cumene, limonene, α-thuyene, α-pinene, ß-phellendrene, p-cymene, γ-terpinene, sabinene and terpinolene.

Extraction of the volatile oil from Carum carvi of Tunisia and Lithuania by supercritical carbon dioxide: chemical composition and antiulcerogenic activity.

This study investigates whether the essential oil prepared from Carum carvi seeds exhibits antiulcerogenic activity. Its volatile oil was obtained by supercritical fluid extraction (SFE) and by hydrodistillation. The essential oils were analysed by GC-MS to monitor their composition. The chemical analysis revealed that the essential oils extracted under SFE conditions had high carvone and limonene contents. The antiulcerogenic activity was evaluated by the HCl/ethanol method, which causes injury to the gastric mucosa. Three treated groups received the essential oil (100-300 mg/kg). The reference group received omeprazole (30 mg/kg) and the control group received NaCl. After 30 min, all groups were treated with HCl/EtOH for gastric ulcer induction. The results show C. carvi essential oil enhanced a significant inhibition of 47%, 81% and 88%, respectively, for three doses of essential oil used, which was similar to that induced by omeprazole (95%) (p < 0.005).