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1.
The subject of the study was investigation of impact of extracts from sunflower and mustard leaves on growth of mustard seedlings. Seeds of mustard were germinated on water and then grew on aqueous extracts from sunflower or mustard leaves. The specific thermal power during seedlings growth was measured by isothermal calorimetry. Changes in the chemical composition stimulated by extracts were measured by FT-Raman spectroscopy and analyzed with the support of the cluster analysis. The heat production rate during growth of seedlings was related to the type of extracts. Crude sunflower and mustard extracts strongly inhibited the growth of seedlings when compared to non-treated control. FT-Raman spectroscopy confirms that allelopathic compounds have the greatest influence on the metabolism of fatty acids of mustard cotyledons. The obtained results indicate that sunflower and mustard extracts have varied impact on growth and heat production rate of mustard seedlings.  相似文献   

2.
In order to better understand the processes of allelopathic interactions and to elucidate the impact of various herbal extracts on seedling growth, investigations were initiated using isothermal calorimetry as a monitor. Seeds of wheat, mustard, rape and clover were germinated on aqueous herbal extracts from arnica, hypericum, milfoil, ribwort, sage and sunflower for 24 h (until the root was visible). Then, five seedlings were put into a calorimeter ampoule with herbal extracts. The specific thermal power (=heat production rate) of the seedlings during their growth was measured by isothermal calorimetry at 20 °C. Heat rate data were collected for 48 h. As a control seedlings were grown on water. The patterns of the thermal power–time curve during seedling growth on the herbal extracts and on water were completely different. In comparison with the water control, seedling growth on the herbal extracts was accompanied by a strong exothermic peak (first phase), whereas in the second phase distinct endothermic peaks were observed. The time after which the maxima of exo- and endothermic peaks occurred strongly depended on the seedling species and the origin of herbal extract. Similarly, the total thermal effect connected with seedling growth was correlated with the seedling species and herbal extract type.  相似文献   

3.
Isothermal calorimetry is a powerful technique for the study of kinetics of physical, chemical, and biological processes, for example, of their temperature dependence. A new heat conduction calorimeter that simultaneously makes measurements on four samples at four different temperatures is presented in this article. Results from tests with four biological systems (milk fermentation, carrot juice spoilage, sunflower seed germination, and moss respiration) are shown. In all the cases, the instrument could measure the heat production rate—and thus the process rate—at the different temperatures used.  相似文献   

4.
The main triacylglycerol (TAG) composition of different plant oils (almond, avocado, corn germ, grape seed, linseed, mustard seed, olive, peanut, pumpkin seed, sesame seed, soybean, sunflower, walnut and wheat germ) were analyzed using two different mass spectrometric techniques: HPLC/APCI-MS (high-performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry) and MALDI-TOFMS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry).Linear discriminant analysis (LDA) as a multivariate mathematical statistical method was successfully used to distinguish different plant oils based on their relative TAG composition. With LDA analysis of either APCI-MS or MALDI-MS data, the classification among the almond, avocado, grape seed, linseed, mustard seed, olive, sesame seed and soybean oil samples was 100% correct. In both cases only 6 different oil samples from a total of 73 were not classified correctly.  相似文献   

5.
Vegetable oils are important constituents of a healthy diet. Still, unsaturated fatty acids present in vegetable oils are susceptible to oxidation, which leads to undesirable changes in sensory, chemical and nutritional properties of oils. To prevent this problem, antioxidants are applied with herbs and spices being one of the most important sources of natural antioxidants. Electron paramagnetic resonance spectroscopy (EPR) can be used to detect free radicals, which are the short-lived intermediates of lipid oxidation, and to monitor changes in oxidation susceptibility. In this study, the ESR spin trapping technique was used as a potential method for the evaluation of the resistance to free radical formation in rapeseed and sunflower oils enriched with herb extracts. The antioxidant effect of herb extracts on vegetable oils was also investigated by measuring their ability to scavenge DPPH free radical using EPR spectroscopy. The herb extracts generally improved the radical scavenging properties of sunflower and rapeseed oils but their influence on the onset of rapid lipid oxidation as measured by spin-trapping EPR depended on the type of oil and on the extract concentration.  相似文献   

6.
Both Indian mustard and sunflower were grown in a hydroponic solution treated with different concentration activities of 134Cs or with different amounts of copper or with both in order to investigate the interaction between copper and radiocesium. It was found that 134Cs activity concentration applied in the nutrient solution exerted more influence on the uptake and translocation of copper by Indian mustard than by sunflower. Indian mustard grown in hydroponic solution containing certain levels of copper and being treated with higher 134Cs activity concentration showed higher uptake of copper than sunflower. However, in the case of root copper concentrations, sunflower showed significantly higher copper immobilization by roots than Indian mustard. It was also found that the presence of copper in the hydroponic solution did modify radiocesium uptake by both species. The application of 1 mg/l in the growth medium could greatly increase the uptake of 134Cs by both species. With 3 mg/l concentration of copper amended to the solution, the accumulation of 134Cs by both species was decreased compared to the 1 mg/l copper treatment. These lines of evidence show that there is stronger interaction between copper and radiocesium in Indian mustard than in sunflower during the root uptake through nutrient solution.  相似文献   

7.
Chemical warfare agents have been stockpiled for almost a decade and their destruction has become an environmental issue that will continue to require attention for many years. There are hundreds of thousands of tonnes yet to be destroyed, and the current chemical or incineration techniques are not without problems. While many researchers are seeking better chemical techniques, we decided to try ionizing radiation to destroy sulphur mustard with the goal of producing non-toxic products. We irradiated a variety of sulphur mustard samples by both a mixed field source (β, γ and neutrons) and a pure gamma source. The mixed field irradiation of wet sulphur mustard for long irradiation times was the most successful at destroying the chemical agent.  相似文献   

8.
The aim of this paper is to study the effect of the pH on the extraction of sinapic acid and its derivatives from mustard seed meal. Solutions of acidic pH (pH 2), basic pH (pH 12) and distilled water (uncontrolled pH ~ 4.5) were tested at different percentages of ethanol. The maximum extraction yield for sinapic acid (13.22 µmol/g of dry matter (DM)) was obtained with a buffered aqueous solution at pH 12. For ethyl sinapate, the maximum extraction yield reached 9.81 µmol/g DM with 70% ethanol/buffered aqueous solution at pH 12. The maximum extraction yield of sinapine (15.73 µmol/g DM) was achieved with 70% ethanol/buffered aqueous solution at pH 2. The antioxidant activity of each extract was assessed by DPPH assay; the results indicated that the extracts obtained at pH 12 and at low ethanol percentages (<50%) exhibit a higher antioxidant activity than extracts obtained at acidic conditions. Maximum antioxidant activity was reached at pH 12 with buffer solution (11.37 mg of Trolox Equivalent/g DM), which confirms that sinapic acid-rich fractions exhibit a higher antioxidant activity. Thus, to obtain rich antioxidant extracts, it is suggested to promote the presence of sinapic acid in the extracts.  相似文献   

9.
In this study, fossil (Sequoioxylon) wood from the Oligocene–Miocene transition in İstanbul, Turkey was examined using non-destructive test methods to evaluate changes in anatomical and chemical structure. Molecular changes in the cell wall structure of the wood were determined using Fourier transform infrared (FTIR) and FT-Raman spectroscopy, along with the comparison to recent wood [Sequoiadendron giganteum (Lindl.)]. We found that the cell wall carbohydrates of the fossil wood were significantly more degraded compared with lignin; FT-Raman spectroscopy revealed the degradation in more detail compared with FTIR spectroscopy. FT-Raman spectra also demonstrated that hemicellulose and holocellulose were decreased in the fossil wood. Laser-induced breakdown spectroscopy (LIBS) analysis confirmed that the mass loss was due to the decreased H and O content of the fossil wood sample and was caused by decomposition. Light microscopy also showed that fossil and recent woods have similar anatomic structures, and that the micro-morphological structure of the fossil wood was well-preserved.  相似文献   

10.
Neutron activation analysis (NAA) technique has been used for the estimation of Mn, Na, and K in different varieties of oil seeds of mustard and sunflower in India. The samples were irradiated in a252Cf source with neutron flux of 109 n s–1 and the analysis was done using a multichannel analyzer (MCA) coupled to high purity germanium (HPGe) detector. Different varieties of seeds are found to have different concentrations of tracer elements when compared among themselves.  相似文献   

11.
The heat capacity of 4,4′-dinitrodiphenyl ether and 4-nitro-4′-biphenylcarboxylic acid were measured by adiabatic calorimetry (AC) in temperature ranges of 8–372 K and 10–372 K, respectively. The heat capacity of 4,4′-dinitrodiphenyl ether in the temperature range 323–500 K, the thermodynamic properties of fusion, and the purity of the ether were measured by differential scanning calorimetry (DSC). The main thermodynamic functions in the temperature range 5–370 K were calculated for both compounds using the heat capacities of adiabatic calorimetry. Related thermodynamic functions of 4,4′-dinitrodiphenyl ether in the temperature range 370–500 K were calculated on the basis of DSC data.  相似文献   

12.
The structure and the electrochemical and spectral properties of two conductive electrochemically polymerized substituted bipyrroles 4,4′-methoxy-2,2′-bipyrrole and 4,4′-buthoxy-2,2′-bipyrrole were studied and compared. The polymers were characterized by cyclic voltammetry, FT-Raman spectroscopy, scanning electron microscopy, and in situ conductivity measurements at different pH and redox state.  相似文献   

13.
Plant seeds accumulate and store phosphorus for the initial growth of seedlings. Phosphorus speciation by 31P nuclear magnetic resonance spectroscopy of NaOH–EDTA seed extracts showed that P was mainly present in organic forms such as phytate and α- and β-glycerophosphate in poppy, sesame, mustard, fennel, and cumin seeds. The inorganic P forms present included orthophosphate and pyrophosphate. The highest concentration of orthophosphate was found in NaOH–EDTA extracts of fennel seeds (41.7%) and the lowest in mustard (9.3%) and sesame seeds (6.9%). For the organic P forms, the highest concentration of phytate was found in mustard seeds (85.2%) and the lowest in fennel seeds (43.3%). Other organic P forms detected were α- and β-glycerophosphate ranging from 1.2 to 5.1% and 0.7 to 2.1%, respectively. Pyrophosphate was detected in trace amounts only in fennel (0.7%) and poppy seeds (0.5%). The only orthophosphate diester observed was in sesame seeds at a low concentration (0.7%), while phosphonates and polyphosphates were not present in any seeds. Phytate was the most dominant P form in all seeds except for fennel and cumin, which contained the lowest phytate concentration but the highest orthophosphate and glycerophosphate concentrations. These results suggest that P transferred from the plant vegetative parts to the developing seeds during maturation is converted to phytate (organic P) in addition to being stored as orthophosphate (inorganic P).  相似文献   

14.
Differential scanning calorimetry and thermogravimetry techniques were successfully used for stability studies of capecitabine. Decreasing values of melting temperature, heat of fusion, and peak purity calculated from the Van’t Hoff equation indicated the gradual decomposition of capecitabine stored at 40 °C in 75% of relative humidity. The increase in mass loss connected with the water sorption was observed simultaneously. High performance liquid chromatography proved the results of thermoanalytical studies. Infrared spectroscopy (IR) appeared to have the lower sensitivity for the decomposition products detection.  相似文献   

15.
 Strong luminescence bands can be present in NIR-excited FT-Raman spectra of certain inorganic materials like hydroxyapatite. Since the origin of these emissions exclusively occurring on NIR-excitation is still unclear, a variety of synthetic and mineral apatites and related calcium salts was studied by means of Stokes and anti-Stokes FT-Raman spectroscopy, X-ray diffraction, and geochemical analyses. The results indicate that the occurrence of the luminescence is in some way related to foreign ion contents. However, a direct correlation to a specific ion could not be found on the basis of available data.  相似文献   

16.

This study is concerned with the investigation of the impact of heat flux on the fire hazard and the effective heat of combustion of sunflower seed hull pellets. Pellets produced by pressing common sunflower seed hulls (Helianthus annuus L.) were investigated. The samples were dried on water content of 0 mass% at a temperature of 103 ± 2 °C. The fire hazard and the heat of combustion have been determined via the cone calorimeter and by the testing procedure per ISO 5660-1:2015 at three heat fluxes (25, 35 and 50 kW m−2). The peak heat release rate increases with the increasing of the heat flux from 446 (at a heat flux of 25 kW m−2) to 601 kW m−2 (at a heat flux of 50 kW m−2). The carbon monoxide yield lies in the interval from 82.50 (at a heat flux of 25 kW m−2) to 154.15 g kg−1 (at a heat flux of 50 kW m−2). The effective heat of combustion decreases with the increasing of the heat flux from 15.84 (at a heat flux of 25 kW m−2) to 14.58 MJ kg−1 (at a heat flux of 50 kW m−2).

  相似文献   

17.
Interpenetrating polymer network hydrogels composed of poly(ethylene glycol) macromer (PEGM) and chitosan were synthesised by UV irradiation of solutions in a mild aqueous media. The IPN hydrogels exhibited the equilibrium water content (EWC) in the range of 86-94%. The hydrogels were characterised using FT-IR, FT-Raman spectroscopy and differential scanning calorimetry (DSC). The results from DSC measurements indicate that the melting endotherms of PEGM, within the hydrogels, decreased in intensities and shifted to lower temperatures comparing with a linear PEGM. This was due to the decrease of the crystallinity in the IPN hydrogels with higher contents of PEGM. The electrical response of the IPN hydrogels was also investigated by applying electrical current to the hydrogels immersed in a NaCl solution. The extent of a bending degree of the IPN hydrogel depends on the IPN hydrogel composition and applied electric field strength.  相似文献   

18.
The present study was conducted to determine and compare the oxidative stability of soybean and sunflower oils using differential scanning calorimetry (DSC). These edible oils were enriched with marjoram (Origanum majorana L.), thyme (Thymus vulgaris L.), and oregano (Origanum vulgare L.) extracts at three different concentrations and synthetic antioxidant (BHA). The fatty acid composition of studied oils was determined by gas chromatography mass spectrometry to evaluate the content of unsaturated fatty acids that are sensitive to oxidation process. Oil samples were heated in the DSC at different heating rates (4.0, 7.5, 10.0, 12.5, and 15.0 °C min?1) and oxidation kinetic parameters (activation energy, pre-exponential factor, and oxidation rate constant) were calculated. The results showed that the oxidative stability of sunflower oil samples enriched with oregano extracts and soybean oil supplemented with thyme extracts was improved compared to samples without the addition of herbal plant extracts and the synthetic antioxidant.  相似文献   

19.
We investigated the effects of cysteine on β-lactoglobulin interactions using ultrasound spectroscopy, rheological measurements, and differential scanning calorimetry. Changes in ultrasonic velocity and attenuation were monitored using ultrasound spectroscopy, and we discuss the effects of cysteine on gel formation together with the results obtained using other methods. A decrease in ultrasonic velocity occurred around 54 °C, suggesting that the compressibility of the system increases at approximately this temperature. An increase in ultrasonic attenuation was observed at approximately 54 °C, which is much lower than the commonly observed denaturation temperature of 75–80 °C. The temperature coincided with the onset of phase transition by differential scanning calorimetry and the initial rise in temperature of dynamic modulus for rheological measurements under heat treatment. We conclude that cysteine promotes the polymerization processes of denatured proteins during the initial stage of gelation. The ultrasonic spectroscopic analysis is a useful tool to monitor protein molecule interactions prior to gelation.  相似文献   

20.
The composition and content of polysaccharides recovered from various samples of sunflower husks by their sequential treatment with water, ammonium oxalate (or oxalic acid), and alkali were examined. The products were analyzed by X-ray diffraction and IR spectroscopy. Original Russian Text L.A. Zemnukhova, S.V. Tomshich, A.V. Kovekhova, L.Yu. Greben’, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80, No. 7, pp. 1200–1205.  相似文献   

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