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1.
Subject  Essential oil from berries of Juniperus oxycedrus L. from two different locations (Mt. Holomontas and Mt. Pindos) was analyzed by GC/MS. Quantitative differences in yield and oil components were found between the two locations. The major components of the berry oil were myrcene (23.4–24.3%), citronellol (16.3–26.8%) and α-pinene (14.4–16.7%):  相似文献   

2.
The aim of the present study was to investigate the essential oil extracted from pine nut shells and its potential application. The essential oil was extracted by steam distillation method and analyzed by gas chromatography coupled with mass spectrometry. Forty-eight volatile chemical compositions were determined and identified. α-Pinene, β-pinene, 3-carene, 1-methy-4-(1-methylethenyl)-(S)-cyclohexene, and n-hexadecanoic acid are predominant volatile compositions in pine nut shells.  相似文献   

3.
The essential oils of Foeniculum vulgare subsp. piperitum were subjected to detailed GC-MS analysis in order to determine possible similarities and differences in their chemical compositions, depending on growth years (2001 and 2002). In both oils, methyl chavicol (40.29 and 21.69%), limonene (17.66 and 22.24%), fenchone (16.90 and 12.98%), α-pinene (1.86 and 34%) and α-phellandrene (2.30 and 2.74%) were the main components, respectively. A total of 32 components were identified accounting for 85.01 and 67.14% of the oils of F. vulgare, respectively. The main characteristic of the oils is the high content of the limonene, fenchone and estragol. Our findings indicated that the oil of Turkish bitter fennel belonged to methyl chavicol rich type.  相似文献   

4.
Ceratocystis fimbriata , Penicillium glabrum und Trichoderma harzianum in Malzextraktbouillon aufgezeigt. In beiden L?sungen war β-Thujaplicin als bekannte pilzhemmende Substanz nachzuweisen, wobei die Konzentrationen bei 2,5 mM (Zedernholzextrakt) und 165 mM (Hiba?l) lagen. Weitere Ergebnisse in diesem Medium zeigten, da? offensichtlich durch die Eigenschaften des Hiba?ls eine Schw?chung der pilzhemmenden Eigenschaft des β-Thujaplicins erfolgte, wohingegen im Zedernholzextrakt weitere pilzhemmende Substanzen vorzuliegen schienen. Auch konnte die pilzhemmende Aktivit?t von Hiba?l und Zedernholzextrakt gegen die genannten Schimmelpilze auf Kiefernholz best?tigt werden, wobei die Wirkung des Hiba?ls wesentlich ausgepr?gter war.
Ceratocystis fimbriata , Penicillium glabrum, and Trichoderma harzianum could be demonstrated in malt extract broth. In both solutions, β-thujaplicin as a known antifungal substance could be detected. The concentrations were 2.5 mM (red cedar heartwood extract) and 165 mM (hiba oil). Further results using this growth medium showed that the antifungal activity of β-thujaplicin in hiba oil was obviously decreased due to properties of the oil, whereas other antifungal substances seemed to be present in the cedar extract. Furthermore, the antifungal activity of hiba oil and red cedar heartwood extract could be confirmed on pine wood. In this case, the effect of the hiba oil was much more pronounced.
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5.
 In nature tocotrienols (compounds of vitamin E) have only been found in the 2R,3′trans,7′trans (R, trans-trans) configuration whereas synthetic tocotrienols often represent a mixture of cis and trans side chain isomers. In this study tocotrienols were isolated from samples (egg yolk, palm oil, and ewe's milk) by extraction of the unsaponifiable matter and subsequent semi-preparative high-performance liquid chromatography (HPLC). A recently developed HPLC method [two series-connected columns ET 200/4 NUCLEODEX β-PM (200×4 mm ID, permethylated β-cyclodextrin phase; Macherey-Nagel, Düren, Germany), acetonitrile/water eluent (58 : 42 by vol.), fluorescence detection at an emission wavelength of 330 nm (excitation wavelength = 295 nm)] was used to separate the isolated tocotrienols into the four potential cis/trans side chain isomers. Commercially available, synthetic α-tocotrienol was orally administered to a laying hen. In the egg yolk all four α-tocotrienol geometrical isomers could be determined, thus demonstrating the bioavailability. Furthermore, no cis/trans isomers of γ-tocotrienol from hardened palm oil (melting point 46  °C) could be detected, i.e. the hydrogenation process during oil hardening evidently caused no isomerization of γ-tocotrienol. Finally, it is shown that ewe's milk does not contain a detectable amount of cis/transα-tocotrienol isomers, which might derive from biohydrogenation during microbial metabolism in the rumen. Received: 9 November 1998 / Revised version: 9 March 1999  相似文献   

6.
D. Don) at 100 °C dry bulb and 70 °C wet bulb, were assessed by measuring the concentration of chemical components in the kiln atmosphere at regular time intervals and determining air-flows and temperature differentials across the stack. The volatile organic compounds (VOC) were trapped on activated carbon and analyzed by GC-MS. The aldehydes were trapped in 2,4-dinitrophenol-hydrazine solution and the aldehyde derivatives analysed by HPLC. Polar compounds were trapped in water and then alcohols were analysed by GC and organic acids by ion exchange chromatography. The two major VOC found were α-pinene and β-pinene, which made up 90% of the total discharge (405 g/m3 wood). Most of the VOC fraction was released during the early stages of drying. The release of potentially hazardous components (formaldehyde, acetaldehyde, furfural) was found to be relatively low (1.1, 8.7, and 0.1 g/m3 wood, respectively) provided the kiln emissions are well dispersed, these levels of release are unlikely to cause adverse environmental effects.  相似文献   

7.
During screening of 20 plant extracts against toxigenic strain of Aspergillus flavus (SK 3NSt), the extract of Cinnamomum tamala was found to exhibit absolute fungitoxic activity (100% growth inhibition). Hence, essential oil of C. tamala was extracted and selected for further investigations. The selected oil was subsequently standardised through physico-chemical and fungitoxic properties. Minimum inhibitory concentration (MIC) of the oil for absolute inhibition of growth of the toxigenic strain of A. flavus (SK 3NSt) was found to be 150 μl/l and oil showed fungicidal nature at its respective MIC. The oil had a broad fungitoxic spectrum. It was found to be absolutely inhibitory to almost all the 11 fungi tested when its fungitoxic spectrum was assayed. The antifungal potency of oil was found to be greater in comparison to some prevalent synthetic fungicides. The oils had the potency to withstand high inoculum density. The oil remained active up to 2 years and was thermostable. In addition, the oil showed significant efficacy in arresting aflatoxin B1 secretion by the toxigenic strain (SK 3NSt) of A. flavus at 750 μl/l. GC-MS analysis of the oil led to the identification of main components of oil viz. eugenol (45.58%), β-pinene (10.03%), β-myrcene (9.73%), β-ocimene (4.51%), β-costol (3.88%) and thujyl alcohol isomer (2.51%). The efficacy of C. tamala oil as aflatoxin B1 suppressor is being reported for the first time. Eugenol, the major component of oil showed absolute antiaflatoxigenic efficacy even at 250 μl/l. The high LD50 value (16.94 ml/kg body weight) of oil recorded on mice indicates its non-mammalian toxicity and suggests the recommendation of the oil as a novel and safe post-harvest biological preservative of food commodities for their preservation from contaminating fungi.  相似文献   

8.
Hydrolytic enzymes, viz. α- and β-glucosidase, were produced from indigenous isolate, Lactobacillus acidophilus, isolated from fermented Eleusine coracana. Production of these enzymes was enhanced by optimizing media using one factor at a time followed by response surface methodology. The optimized media resulted in a 2.5- and 2.1-fold increase in α- and β-glucosidase production compared with their production in basal MRS medium. Localization studies indicated 80% of the total activity to be present in the cell membrane-bound fraction. Lack of sufficient release of these enzymes using various physical, chemical, and enzymatic methods confirmed their unique characteristic of being tightly cell membrane bound. Enzyme characterization revealed that both α- and β-glucosidase exhibited optimum catalytic activity at 50 °C and pH 6.0 and 5.0, respectively. K m and V max of α-glucosidase were 4.31 mM and 149 μmol min−1 mL−1 for p-nitrophenyl-α-d-glucopyranoside as substrate and 3.8 mM and 120 μmol min−1 mL−1 for β-glucosidase using p-nitrophenyl-β-d-glucopyranoside as the substrate.  相似文献   

9.
 Profiles of steroid hormones (androgens, estrogens, progestogens and corticoids), their precursors and metabolites were analyzed in nine beef samples obtained from steers which had received the anabolic implant Synovex-S (200 mg progesterone plus 20 mg estradiol benzoate) and in nine samples from control steers. Analysis of phenolic steroids was performed by enzyme immunoassay after separation by HPLC. Neutral steroids were determined by GC-MS. Concentrations of the hormones progesterone and 17β-estradiol, of their precursors and metabolites (pregnenolone, 17α-hydroxyprogesterone, dehydroepiandrosterone, androstenedione, epitestosterone, α-androsterone, 17α-estradiol, and estrone) and of the corticosteroids cortisone and hydrocortisone did not differ significantly between treatments (P>0.05) but the ratio of 17β-estradiol to its metabolites and the cortisone/hydrocortisone ratio were significantly higher in beef from treated steers (P<0.01). Concentrations of testosterone and 5α-dihydrotestosterone were below the determination limits (10 ng/kg and 20 ng/kg, respectively) in both treated and control steers.  相似文献   

10.
Nineteen odour-active compounds previously identified with high Flavour Dilution factors in an extract from the peel oil of Pontianak oranges (Citrus nobilis Lour. var. microcarpa Hassk.) were quantified using stable isotope dilution assays (SIDA). For this purpose, four new SIDA were developed, i.e. for the quantification of (E)-2-dodecenal, geraniol, nerol, and 1-phenylethanethiol. The results showed that (R)-limonene, myrcene, and (R)-α-pinene were the predominant compounds present in concentrations between 0.4 and 60 mg/g peel. An aroma recombinate containing the nineteen aroma compounds in the concentrations naturally occurring in the peel oil elicited the overall aroma of the peel oil itself, thus confirming the identification experiments. Furthermore, omission experiments showed that the unique odour quality of the peel is significantly influenced by the resinous, sulphurous-smelling 1-phenylethanethiol, although its concentration was only 38 ng/g peel.  相似文献   

11.
Response surface methodology was used to optimize the peroxidase-catalyzed enzymatic degradation of aflatoxin B1 (AFB1) from red chili powder. Twenty experiments were carried out using central composite rotatable design with three independent variables (enzyme concentration, substrate or AFB1 concentration, and incubation time) and single response (% aflatoxin B1 degradation). The optimum conditions achieved after numerical and graphical optimizations for maximum percent degradation were: AFB1 (31.5 nM), enzyme (13.5 U/nM AFB1), and time (26 h). The actual percent degradation achieved at these optimum conditions was 70.0% and predicted 74.5%. The reduced quadratic model developed for the experimental data was found adequate to describe the relationships between the operating variables (Model F = 21.61, p < 0.001; F lof = 3.63, p > 0.05). The robustness of the model was tested by confirmation experiments, and difference was found insignificant between the actual and predicted values as confirmed by two-tailed t test (α = 0.05). The hepatotoxic effect of the AFB1 pre- and post-detoxification was tested on Wistar rats. The detoxified powder was also tested for changes in ascorbic acid, β-carotene, ASTA color value, and capsaicin content. Capsaicin was resistant to enzymatic degradation under specified conditions, but loss of around 15% was reported in color and β-carotene content; the loss in ascorbic acid was 10%.  相似文献   

12.
 The volatile oil compositions of Eucalyptus camaldulensis var. brevirostris leaves obtained by hydrodistillation (HD) and supercritical fluid extraction methods (SFE) were analysed qualitatively and quantitatively by GLC-MS. Ninety different components were separated and most of them identified. In both extracts the main constituents were found to be β-phellandrene (8.94 and 4.09%), p–cymene (24.01 and 10.61%), cryptone (12.71 and 9.82%) and spathulenol (14.43 and 13.14%). The yield of the monoterpene hydrocarbons in HD oil (0.288 g/100 g fresh leaves) was slightly higher compared with that in the SFE extract (0.242 g/100 g fresh leaves). The SFE extract possessed higher concentrations of the sesquiterpenes, light oxygenated compounds and heavy oxygenated compounds than the HD oil. The relationship between the antioxidant activity and chemical composition of the extracted oils was investigated. The significant amounts of p–cymen-7-ol and thymol are responsible for the antioxidative activity of both extracts. The concentration of both compounds, but especially that of p–cymen-7-ol (2.25%), is higher in the SFE extract. This corresponds with the higher antioxidative activity of the SFE compared with the HD extract. p–Cymen-7-ol, a compound newly identified in leaves of Eucalyptus species, exhibited superior antioxidant activity in comparison with that of butylated hydroxyanisole.  相似文献   

13.
 The volatile oil compositions of Eucalyptus camaldulensis var. brevirostris leaves obtained by hydrodistillation (HD) and supercritical fluid extraction methods (SFE) were analysed qualitatively and quantitatively by GLC-MS. Ninety different components were separated and most of them identified. In both extracts the main constituents were found to be β-phellandrene (8.94 and 4.09%), p–cymene (24.01 and 10.61%), cryptone (12.71 and 9.82%) and spathulenol (14.43 and 13.14%). The yield of the monoterpene hydrocarbons in HD oil (0.288 g/100 g fresh leaves) was slightly higher compared with that in the SFE extract (0.242 g/100 g fresh leaves). The SFE extract possessed higher concentrations of the sesquiterpenes, light oxygenated compounds and heavy oxygenated compounds than the HD oil. The relationship between the antioxidant activity and chemical composition of the extracted oils was investigated. The significant amounts of p–cymen-7-ol and thymol are responsible for the antioxidative activity of both extracts. The concentration of both compounds, but especially that of p–cymen-7-ol (2.25%), is higher in the SFE extract. This corresponds with the higher antioxidative activity of the SFE compared with the HD extract. p–Cymen-7-ol, a compound newly identified in leaves of Eucalyptus species, exhibited superior antioxidant activity in comparison with that of butylated hydroxyanisole. Received: 30 April 1998  相似文献   

14.
A high performance liquid chromatography/ultraviolet method developed for the simple and direct determination of β-hydroxy-β-methylbutyrate (HMB) in liquid nutritional products and dietary supplements is described. Method suitability was defined by experimental assessments of linearity (r 2 > 0.9999), precision (day-to-day RSD <1.5%), accuracy (spike recoveries = 98.1–102.4%, n = 28), selectivity (peak purity average = 99.8 ± 0.8%, n = 10; absence of interference verified by placebo analysis), and quantitation limit (90 mg/kg or 0.8 mM). The method provides for a simple, accurate, and precise quantification of HMB, when present at millimolar concentrations in liquid nutritional products and dietary supplements.  相似文献   

15.
The essential oil of Monodora myristica was obtained by steam distillation with a yield of 45-6 g kg?1. The composition of the oil was analysed by gas chromatography and gas chromatography-mass spectrometry. The oil was found to contain 75% monoterpene hydrocarbons; the major compounds being α-phellandrene (50–4%), α-pinene (5–5%) and myrcene (4–35%). There were also a few sesquiterpene hydrocarbons (3%) and oxygenated compounds such as germacrcne-D-4-ol (9–5%). Germacrene-D-4-ol, α-pinene, Δ2-carene, β-caryophyllene, valencene. γ-muurolol and carvacryl acetate have not previously been reported in M myristica.  相似文献   

16.
Picea abies ) and Scots pine (Pinus sylvestris) wood under conditions relevant in the high temperature drying process. This paper reports the experimental results obtained for creep in tension under drying conditions at temperatures 95–125 °C. The results are compared to other researchers' measurements of mechano-sorptive creep at conventional drying temperatures (up to 80 °C). Based on this comparison the effect of temperature on the perpendicular to grain mechano-sorptive creep compliance is quantified.
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17.
SUMMARY: The terpene and sesquiterpene hydrocarbons in celery essential oil that was recovered by two different methods were separated from the oxygen containing materials by column chromatography and analyzed by temperature-programmed gas chromatography. The essential oils were prepared from celery puree by a batch distillation procedure, and by vaporization in a Votator Turba-Film evaporator and rectification of the vapors in a packed distillation column. The terpenes α-pinene, β-pinene, myrcene, limonene, γ-terpinene and cymene; and the sesquiterpenes β-elemene, β-caryophyllene, α- and β-humulene and β-selinene were identified as constituents of the essential oils. The qualitative and quantitative relationships of the hydrocarbons between the two different oils were established and discussed.  相似文献   

18.
Corn and vegetables are good sources of vitamins, minerals, and carotenoids. This study reports (1) the effect of processing—blanching, drying, and milling on major carotenoids—lutein (L), zeaxanthin (Z), and β-carotene levels in corn (Zea mays), onion stalk (Allium cepa L), broccoli (Brassica oleracea L), and capsicum (Capsicum annum L), and (2) the bioavailability of L and Z from processed corn in mice. A group of mice were fed with diet containing processed or unprocessed corn (L + Z source) or purified L (control) for 3 weeks. Results from HPLC analysis indicate that the levels of L + Z (19.6–118.5%) and β-carotene (1–84%) were higher in blanched samples compared to fresh samples whereas drying resulted in lower L + Z level in onion stalk (45.5%) and capsicum (36.4%) and was higher in corn (22%) and broccoli (14%) over blanching. The level of β-carotene was slightly higher in broccoli on drying than blanching. Milling did not alter carotenoid levels in any of the samples. Feeding processed corn (blanched + dried + milled) resulted in nonsignificant change in the plasma L + Z level but significantly higher in liver (58.7%) than in control group. Similarly, the level of L + Z in plasma (12.1%) and liver (14.9%) of mice fed on processed corn was higher compared to unprocessed-corn-fed group. Based on the above results, it is concluded that the extractability and bioavailability of L + Z can be improved by blanching corn before its consumption.  相似文献   

19.
 The aroma compounds of extracts of ripe and unripe fruits of Spondias cytherea Sonnerat ("ambarella" or "cajarana") were analysed by GC/FID, GC/MS and olfactometry. As main compounds, 1,8-cineole, α-pinene, β-pinene, terpinolene, limonene, α-terpineol, butyl acetate, γ-terpinene and terpinen-4-ol, among more than 50 constituents, were identified. The characteristic odour impressions of these extracts can be correlated to identified minor alcohols and esters, monoterpenes, hexane derivatives and fatty acids. Received: 6 July 1998  相似文献   

20.
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