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1.
S. R. de Miguel M. C. Romn-Martínez D. Cazorla-Amors E. L. Jablonski O. A. Scelza 《Catalysis Today》2001,66(2-4):289-295
In this paper, a study on the hydrogenation of carvone by using Pt/Al2O3, PtSn/Al2O3, PtGe/Al2O3, Pt/C and PtSn/C is reported. TPR, H2 chemisorption, XPS and test reaction results show that the addition of a second metal to Pt leads to important modifications of the structure of the metallic phase, though these modifications are different according to the nature of the support (Al2O3 or C). The activity and selectivity of these catalysts in carvone hydrogenation depend not only on the composition of the metallic phase, but also on the nature of the support. Thus, adding Sn or Ge to Pt/Al2O3 enhances the selectivity to unsaturated ketones (at a fixed carvone conversion, Xcarv=1). When Pt is supported on activated carbon, small amounts of unsaturated alcohols are observed. The Sn addition to Pt/C sharply enhances the selectivity to carveol formation (the doubly unsaturated alcohol) reaching values close to 100% at the initial stages of the reaction. 相似文献
2.
Smain Chemat Hamid Aït-Amar Ahcne Lagha D.C. Esveld 《Chemical Engineering and Processing: Process Intensification》2005,44(12):1320-1326
The process conditions during the extraction of carvone and limonene from caraway seed (Carum carvi L.) with microwave-assisted extraction have been studied with respect to microwave power, radiation dose and extraction time in order to obtain the secondary metabolites selectively. Using classical solid–liquid extraction, limonene, carvone and fatty oils in both the raw material and the residual matrix material were extracted. Yields of limonene, carvone and total oil (C16, C18) were determined by GC and GC/MS analysis for both extracts. The effects of microwaves on cell walls and cells destruction could be seen on SEM micrographs. 相似文献
3.
Krishnaiah YS Al-Saidan SM Chandrasekhar DV Rama B 《Drug development and industrial pharmacy》2006,32(4):423-435
The objective of the study was to investigate the effect of nerodilol and carvone on the in vitro transdermal delivery of nicorandil so as to fabricate a membrane-moderated transdermal therapeutic system. The in vitro permeation studies were carried across the rat epidermal membrane from the hydroxypropyl methylcellulose (HPMC) gels (prepared with 70:30 v/v ethanol-water) containing selected concentrations of a terpene such as nerodilol (0% w/w, 4% w/w, 8% w/w, 10% w/w, or 12% w/w) or carvone (0% w/w, 4% w/w, 8% w/w, 12% w/w, or 16% w/w). The amount of nicorandil permeated (Q24) from HPMC gel drug reservoir without a terpene was 3424.6 ± 51.4 μg/cm2, and the corresponding flux of the drug was 145.5 ± 2.2 μg/cm2· h. The flux of nicorandil increased with an increase in terpene concentration in HPMC gel. It was increased ranging from 254.9 ± 3.1 to 375.7 ± 3.2 μg/cm2·h or 207.6 ± 4.7 to 356.7 ± 15.3 μg/cm2· h from HPMC gels containing nerodilol (4% w/w to 12% w/w) or carvone (4% w/w to 16% w/w), respectively. Nerodilol increased the flux of nicorandil by about 2.62-folds whereas carvone increased the flux of the drug by about 2.49-folds across the rat epidermal membrane. The results of the Fourier Transform Infrared (FT-IR) study indicated that the enhanced in vitro transdermal delivery of nicorandil might be due to the partial extraction of stratum corneum lipids by nerodilol or carvone. It was concluded that the terpenes, nerodilol and carvone, produced a marked penetration enhancing effect on the transdermal delivery of nicorandil that could be used in the fabrication of membrane-moderated transdermal therapeutic systems. 相似文献
4.
d-Carvone or (4S)-(+)-carvone has a caraway/dill odour and is the main constituent of caraway (Carum carvi) and dill (Anethum graveolens) seed oils whilst l-Carvone or (4R)-(−)-carvone has a sweet spearmint odour and is the main constituent of spearmint (Mentha spicata). Carvone is produced by both extraction and purification of essential oils from caraway, dill and spearmint seeds and by chemical and biotechnological synthesis. 相似文献
5.
《Food Control》2017
Consumer preference for minimally processed foods has steadily increased for several years, while foodborne outbreaks from under-processed foods continue to be reported worldwide. We investigated the combination effect of ohmic heating with various essential oil components for inactivation of foodborne pathogens in buffered peptone water and salsa. We choose carvone, eugenol, thymol, and citral to combine with ohmic heating, which are registered for use as flavorings in foodstuffs. Combination treatment of ohmic heating with citral showed the most synergistic bactericidal effect against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes in buffered peptone water followed by thymol, eugenol, and carvone. When enumerated on selective media, the reductions were 4.8, 5.7, and 4.3 log CFU/ml for E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. Cell membrane destruction by combination treatment and the loss of cell membrane potential by essential oil components were proposed as the bactericidal mechanism. When applied in salsa, inactivation of bacterial pathogens was the greatest with the ohmic and thymol combination treatment followed by citral, eugenol, and carvone. A synergistic virucidal effect was observed for MS -2 bacteriophage, which was used as a norovirus surrogate. Color (b* values) of salsa were improved by combination treatment of ohmic heating and thymol compared to ohmic treated samples. Therefore, the combination treatment of ohmic heating and thymol could be used effectively to pasteurize salsa. 相似文献
6.
Yellela S. R. Krishnaiah Saleh M. Al-Saidan Dantam V. Chandrasekhar Bukka Rama 《Drug development and industrial pharmacy》2013,39(4):423-435
ABSTRACTThe objective of the study was to investigate the effect of nerodilol and carvone on the in vitro transdermal delivery of nicorandil so as to fabricate a membrane-moderated transdermal therapeutic system. The in vitro permeation studies were carried across the rat epidermal membrane from the hydroxypropyl methylcellulose (HPMC) gels (prepared with 70:30 v/v ethanol–water) containing selected concentrations of a terpene such as nerodilol (0% w/w, 4% w/w, 8% w/w, 10% w/w, or 12% w/w) or carvone (0% w/w, 4% w/w, 8% w/w, 12% w/w, or 16% w/w). The amount of nicorandil permeated (Q24) from HPMC gel drug reservoir without a terpene was 3424.6 ± 51.4 μg/cm2, and the corresponding flux of the drug was 145.5 ± 2.2 μg/cm2· h. The flux of nicorandil increased with an increase in terpene concentration in HPMC gel. It was increased ranging from 254.9 ± 3.1 to 375.7 ± 3.2 μg/cm2·h or 207.6 ± 4.7 to 356.7 ± 15.3 μg/cm2· h from HPMC gels containing nerodilol (4% w/w to 12% w/w) or carvone (4% w/w to 16% w/w), respectively. Nerodilol increased the flux of nicorandil by about 2.62-folds whereas carvone increased the flux of the drug by about 2.49-folds across the rat epidermal membrane. The results of the Fourier Transform Infrared (FT-IR) study indicated that the enhanced in vitro transdermal delivery of nicorandil might be due to the partial extraction of stratum corneum lipids by nerodilol or carvone. It was concluded that the terpenes, nerodilol and carvone, produced a marked penetration enhancing effect on the transdermal delivery of nicorandil that could be used in the fabrication of membrane-moderated transdermal therapeutic systems. 相似文献
7.
Toxic compounds in essential oils of coriander, caraway and basil active against stored rice pests 总被引:1,自引:0,他引:1
María D. López 《Journal of Stored Products Research》2008,44(3):273-278
Essential oils, distilled from seeds of Coriander sativum and Carum carvii and from leaves of five different varieties of Ocimum basilicum, were fractionated by column chromatography and tested in the laboratory for volatile toxicity against three stored rice pests (Sitophilus oryzae, Rhyzopertha dominica and Cryptolestes pusillus). The active fractions were analyzed by GC-MS. Coriander contained linalool (1617 ppm of the oil) as the main product active against the three pests. Camphor-rich fractions (over 400 ppm) were very toxic to R. dominica and C. pusillus. The caraway profile included carvone and limonene as expected but (E)-anethole, generally regarded as a minor product in the essential oil of this species, was also a major component, being present at 365 ppm. Carvone was the most effective (972 ppm) monoterpenoid against S. oryzae. In addition, (E)-anethole at 880 ppm was toxic to R. dominica while vapors of limonene (1416 ppm) and fenchone-rich (554 ppm) fractions killed adults of C. pusillus only. Three major essential oil profiles were present in the five varieties of O. basilicum analyzed: methyl eugenol/estragole, estragole and estragole/linalool chemotypes. The abundance of components had a strong influence on the outcome of the bioassays. Fractions, where combinations of products occurred with or without other minor compounds, were often more toxic than any one compound alone. 相似文献
8.
Bark of ten woody species, known to be rejected as a food source by the pine weevil, Hylobius abietis, were sequentially extracted by a Soxhlet apparatus with pentane followed by methanol. Species were alder (Alnus glutinosa), aspen (Populus tremula), beech (Fagus sylvatica), guelder rose (Viburnum opulus), holly (Ilex aquifolium), horse chestnut (Aesculus hippocastanum), lilac (Syringa vulgaris), spindle tree (Evonymus europaeus), walnut (Juglans regia), and yew (Taxus baccata). Bark of each species was collected in southern Scandinavia during the summer. Resulting extracts were tested for antifeedant
activity against the pine weevil by a micro-feeding choice assay. At a dose corresponding to that in the bark, methanol extracts
from Aesculus, Taxus, Ilex, and Populus were antifeedant active, while pentane extracts of Aesculus, Fagus, Syringa, and Viburnum were stimulatory. Four known antifeedants against H. abietis, the straight-chained carboxylic acids, hexanoic and nonanoic acid (C6 and C9), carvone, and carvacrol were identified by
gas chromatography (GC)–mass spectrometry (MS) in several extracts. The major constituents were identified and tested for
feeding deterrence. The aromatic compounds benzyl alcohol and 2-phenylethanol are new non-host plant-derived feeding deterrents
for the pine weevil. Additionally, two feeding stimulants, β-sitosterol and 5-(hydroxymethyl)-2-furaldehyde, were identified.
One active methanol extract of Aesculus bark was sequentially fractionated by liquid chromatography, and major compounds were tentatively identified as branched
alcohols and esters of hexanoic acid. Five commercially available hexanoate esters and two commercially available branched
alcohols were identified as new active antifeedants. Both stimulatory and inhibiting compounds were found in the same extracts
and co-eluted in the same or adjacent fractions. The mix of semiochemicals of opposite activity in each extract or fraction
could explain the stimulatory-, inhibitory-, or sometimes neutral activity. Generally, such co-occurrence confounds the isolation
of antifeedants. 相似文献
9.
Dalmo Mandelli Yuriy N. Kozlov Camilla C. Golfeto Georgiy B. Shul’pin 《Catalysis Letters》2007,118(1-2):22-29
Natural terpenes, (−)-limonene and (+)-carvone, can be epoxidized by peroxyacetic acid (PAA) at room temperature if a dinuclear
manganese(IV) complex with 1,4,7-trimethyl-1,4,7-triazacyclononane (L), [Mn2L2O3] [PF6]2, is used as a catalyst. The total yield of the epoxides based on the consumed olefins are 97 and 95%, respectively. A kinetic
study of the dec-1-ene and cyclohexane oxygenations including the investigation of their simultaneous competitive oxidation
was carried out. The olefin epoxidation rate does not depend on dec-1-ene concentration and the dec-1-ene concentration does
not affect the rate of cyclohexane oxidation. The cyclohexane oxidation rate is proportional to the alkane concentration.
The kinetic analysis led to the conclusion that two species X
1 and X
2 are generated in the system, and there is no their mutual interconversion. The rate equation for the dec-1-ene epoxidation
was proposed: W = k
+1[cat][PAA], where cat is the initial manganese complex or its derivative, and the constant was determined: k
+1 = 3.5 mol−1 dm3 s−1. Species X
1 is apparently an effectively epoxidizing manganese peroxo derivative whereas species X
2 is an alkane hydroxylating manganese oxo complex. 相似文献
10.
Sharon Zietsman Gareth Kilian Matthew Worthington Chris Stubbs 《Drug development and industrial pharmacy》2013,39(2):191-197
ABSTRACTMetronidazole is a synthetic antibacterial and antiprotozoan agent. Crystallization occurs in aqueous metronidazole benzoate suspensions caused by an anhydrate to monohydrate conversion. This study aimed to develop an aqueous metronidazole benzoate suspension that does not exhibit this hydration and the accompanying crystal growth. Four suspending agent systems were evaluated. Xanthan gum and Avicel® RC-591 (a combination of microcrystalline cellulose and carboxymethylcellulose sodium) were found to be the suspending agents that resulted in optimal formulation properties. Monohydrate formation did not occur in product containing Avicel® RC-591, indicating that suspending agents may exert a positive effect on metronidazole benzoate suspension stability. 相似文献