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1.
Volatile and semi‐volatile components of internal and external leaves of Brassica oleracea L. var. costata DC, grown under different fertilization regimens, were determined by headspace solid‐phase microextraction (HS‐SPME) combined with gas chromatography/ion trap mass spectrometry (GC/ITMS). Forty‐one volatiles and non‐volatile components were formally identified and thirty others were tentatively identified. Qualitative and quantitative differences were noticed between internal and external leaves. In general, internal leaves exhibited more aldehydes and sulfur volatile compounds than external ones, and less ketone, terpenes and norisoprenoid compounds. The fertilization regimens influenced considerably the volatile profile. Fertilizations with higher levels of sulfur produced Brassica leaves with more sulfur volatiles. In opposition, N and S fertilization led to leaves with lower levels of norisoprenoids and terpenes. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

2.
We report the spectrophotometric determination of total polyphenols, flavonoids, glucosinolates and antioxidant activity in seeds, seedlings and leaves of Tuscan black kale. The highest content of phytochemicals was observed in 10 days sprouts and antioxidant activity was maximum in 2, 4 days seedlings. Identification and characterisation of phytochemicals were performed by mass spectrometry (MS), high resolution and tandem MS with electrospray ionisation mode. Low-molecular-weight metabolites were evidenced in seeds while metabolites at high m/z range were detected in cotyledons and leaves. MS spectra evidenced different phenolic compounds (flavonoid caffeoyl glucose, hydroxycinnamic acid sinapine) and glucosinolates (glucoerucin, glucobrassicin and glucoraphanin) in function of developmental stage; galactolipids ω3 and ω6 were observed in leaves. Identification of stages with the highest phytochemicals content encourages the consumption of black kale sprouts and young leaves. Our research can support food and pharmaceutical industries for production of health promoting products from black kale.  相似文献   

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ABSTRACT

This study reports the synthesis of ZnO nanoparticles using the aqueous solution of broccoli extract. The nanoparticles, represented as broc-ZnO (with broccoli extract) and nb-ZnO (without broccoli extract), were obtained after calcination. The nanoparticles were characterized using X-ray diffraction (XRD), Transmission electron microscopy (TEM), Fourier Transform infra-red (FTIR), Energy dispersive spectroscopy (EDX), UV-visible spectroscopy (UV) and Photoluminescence (PL). Hexagonal phases were identified for both nanoparticles, while average crystallite sizes of 14 and 17?nm for broc-ZnO and nb-ZnO, respectively, were obtained. UV studies indicated the bandgap of the broc-ZnO and nb-ZnO as 4.09 and 3.87?eV, respectively. A plausible mechanism for the synthesis of the nanoparticles was suggested. The photocatalytic efficiency of broc-ZnO, obtained via the broccoli extract, was evaluated by studying its photo-enhanced catalytic activity against methylene blue (MB) and phenol red (PR), under UV light irradiation and 74% and 71% degradation efficiency of the successive dyes were achieved.  相似文献   

5.
In this paper, biological investigations and a high-resolution UPLC-PDA-ESI-qTOF-HRMS technique were employed for Brassica oleracea L. var. capitata f. rubra DC. (red cabbage) of the family Brassicaceae (Cruciferae), cultivated in Egypt, for the first time. The positive ionization mode is usually performed to identify anthocyanins. However, this technique cannot differentiate between anthocyanins and corresponding non-anthocyanin polyphenols. Thus, the negative ionization mode was also used, as it provided a series of characteristic ions for the MS analysis of anthocyanins. This helped in identifying five kaempferol derivatives for the first time in red cabbage, as well as nine—previously reported—anthocyanins. For the biological investigations, the acidified methanolic extract of fresh leaves and the methanolic extract of air-dried powdered leaves were examined for their antioxidant, antimicrobial, and anticancer activities. The freshly prepared phenolic extract was proven to be more biologically potent. Statistical significance was determined for its anticancer activity in comparison with standard doxorubicin.  相似文献   

6.
Abstract

Rhaponticum acaule (L.) DC. is a medicinal plant commonly used for the treatment of some illnesses such as gastrointestinal infections. In this work, we report the composition of different parts of this plant on phenolic compounds, their quantification, and antioxidant activity. The obtained results reported that methanolic extracts of the three parts studied revealed high phenolic contents. For flavonoid contents, the highest contents were reported in organic extracts of leaf part. In addition, results obtained from the study of the antioxidant activity showed that methanolic extract of root presented the highest activity, in DPPH? scavenging ability test with an IC50 of 0.31?±?0.04?mg/mL and in FRAP test with an EC50 of 1.06?±?0.02?mg/mL. The RP-HPLC-PDA analysis revealed the presence of five phenolic acids (sinapic, caffeic, chlorogenic, ferulic and syringic acids), one flavanone (naringenin), one flavonol (rutin) and vanillin.  相似文献   

7.
The flavonoid composition of broccoli inflorescences has been studied by LC/UV-DAD/ESI-MSn. A large number of hydroxycinnamic acid esters of kaempferol and quercetin glucosides has been characterised. The structures of the flavonoid glycosides were analysed after alkaline hydrolysis, and were identified as 3-sophoroside/sophorotrioside-7-glucoside/sophoroside of kaempferol, quercetin and isorhamnetin (this last found in trace amount). These complex quercetin and isorhamnetin glucosides have not been previously characterised in nature. In addition, several less complex glucosides based on the same aglycones have been identified. The effect of sugar substitution and acylation on chromatographic mobility and ESI ionisation and fragmentation are discussed.  相似文献   

8.
Abstract

A new lignan, named oleralignan (1) and three known componds (+)-syringaresinol (2), (+)-lirioresinol A (3) and monomethyl 3,3′,4,4′-tetrahydroxy-δ-truxinate (4) were isolated from the P. oleracea for the first time. The compound (1) were identified by 1D, 2D NMR spectroscopic methods and high resolution electrospray ionization time-of-flight mass spectrometry. In addition, it was found that the four lignans presented the scavenging activities in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay more than that of hydroxyl anisole (BHA).

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9.
We report an extensive chemical characterisation of fatty acids, triacylglycerols, tocopherols, carotenoids and polyphenols contained in the oil extracted from old cabbage (Brassica oleracea L. var. acephala) by cold-pressing of the seeds. Analyses were performed by GC-FID combined with mass spectrometry, HPLC with photodiode array, fluorescence and mass spectrometry detection. The 94% of the total fatty acids were unsaturated, rappresented by erucic acid (more than 50%) followed by linoleic, linolenic and oleic acids accounting for approximately 10% each. The most abundant triacylglycerols (>13%) were represented by erucic–gadolenic–linoleic, erucic–eruci–linoleic and erucic–erucic–oleic. Among tocopherols, γ-tocopherol accounted for over 70% of the total content. Thirteen carotenoids and 11 polyphenols were identified and measured. In particular, the total content in carotenoids was 10.9 ppm and all-E-lutein was the main component (7.7 ppm); among polyphenols, six hydroxycinnamic acids and five flavonoids, were identified by combining information from retention times, PDA and MS data.  相似文献   

10.
The biological activities of the primary metabolites and secondary metabolites of 69 green cabbage varieties were tested. The LC-MS detection method was used to determine the content of 19 free amino acids (lysine, tryptophan, phenylalanine, methionine, threonine, isoleucine, leucine, valine, arginine, asparagine, glycine, proline, tyrosine, glutamine, alanine, aspartic acid, serine, and glutamate). The content of 10 polyphenols (chlorogenic acid, gallic acid, 4-coumaric acid, ferulic acid, gentisic acid, cymarin, erucic acid, benzoic acid, rutin, and kaempferol) was determined by the HPLC detection method. Considering the complexity of the data obtained, variance analysis, diversity analysis, correlation analysis, hierarchical cluster analysis (HCA), and principal component analysis (PCA) were used to process and correlate amino acid or polyphenol data, respectively. The results showed that there were significant differences between the different amino acids and polyphenols of the 69 cabbage varieties. The most abundant amino acids and polyphenols were Glu and rutin, respectively. Both amino acids and polyphenols had a high genetic diversity, and multiple groups of significant or extremely significant correlations. The 69 cabbage varieties were divided into two groups, according to 19 amino acid indexes, by PCA. Among them, seven varieties with high amino acid content all fell into the fourth quadrant. The HCA of amino acids also supports this view. Based on 10 polyphenols, the 69 cabbage varieties were divided into two groups by HCA. Based on 29 indexes of amino acids and polyphenols, 69 cabbage varieties were evaluated and ranked by PCA. Therefore, in this study, cabbage varieties were classified in accordance with the level of amino acids and polyphenols, which provided a theoretical basis for the genetic improvement of nutritional quality in cabbage.  相似文献   

11.
Peroxidase was purified in a single step using 4-amino benzohydrazide affinity chromatography from red cabbage (Brassica oleracea var. capitata f. rubra), and some important biochemical characteristics of the purified enzyme were determined. The enzyme, with a specific activity of 3,550 EU/mg protein, was purified 120.6-fold with a yield of 2.9 % from the synthesized affinity matrix. The molecular weight of the enzyme was found to be 69.3 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme exhibited maximum activity at pH 7.0 and 30 °C. For guaiacol substrate, the K m and V max values were found as 0.048 mM and 1.46 EU/mL/min, respectively. Additionally, the IC50 and K i values for 4-amino benzohydrazide were calculated to be 1.047 and 0.702?±?0.05 mM, respectively, and 4-amino benzohydrazide showed noncompetitive inhibition.  相似文献   

12.
应用高效液相色谱-电喷雾/四极杆飞行时间串联质谱联用技术分析了紫甘蓝和羽衣甘蓝中的花色苷成分.选用Agilent TC-C18色谱柱(250 mm×4.6 mm×5 μm),二元线性梯度洗脱,柱后流出液采用电喷雾四极杆飞行时间质谱的正、负离子模式进行检测.根据一级质谱的分子离子和二级质谱碎片离子,获得化合物的准确分子量...  相似文献   

13.
Hydrothermal treatment of Brussels sprouts (Brassica oleracea var. gemmifera) induces both physical and chemical changes in nutrients and non-nutrients. It also affects the bioaccessibility of individual compounds. The aim of this study was to investigate the influence of hydrothermal treatment (boiling, steaming, and sous vide technique) on the concentration of the selected nutrients and non-nutrients in Brussels sprouts and in vitro bioaccessibility of the mineral components. It has been shown that, in terms of the leaching of nutrients and non-nutrients into the aqueous medium, traditional cooking in water involves the greatest percentage loss (the highest decrease in dry matter (11.8%), ash (13.3%), protein (10.4%), crude fat (43.3%), dietary fiber (9.5%), digestible carbohydrates (12.2%), and most of mineral components (7.6–39.8%)). In contrast, steam cooking and sous vide cooking of Brussels sprouts allow a higher level of preservation of the individual compounds. By using reduced process temperatures and vacuum packaging, sous vide cooking can be an alternative to traditional cooking to preserve the higher nutritional value of Brassica oleracea var. gemmifera (preservation of dry matter, ash, crude fat, and most of the mineral components at the level of the raw sample p ≤ 0.05).  相似文献   

14.
Sulforaphane (SFN) is a powerful health-promoting compound found in broccoli in the form of its inactive precursor, glucoraphanin (GFN). SFN formation occurs through the enzymatic hydrolysis of glucoraphanin by myrosinase under specific chemical conditions. Its incorporation in food formulations has been hindered by the thermal instability of SFN and low concentration in Brassicaceae. Then, extracting SFN from broccoli at a temperature below 40 °C appears as an option to recover and stabilize SFN, aiming at delivering it as a nutraceutical. We studied an eco-friendly extraction process to obtain an SFN-rich extract from broccoli. The effect of the broccoli mass/solvent ratio, ethanol concentration in the extractant solution, and extraction time on the recovery of SFN, GFN, phenolic compounds, and antioxidant activity were studied through a Box–Behnken design. The regression models explained more than 70% of the variability in the responses, adequately representing the system. The experimental factors differently affected the bioactive compound recovery and antioxidant activity of the extracts. The extraction conditions that allowed the highest recovery of bioactive compounds and antioxidant activity were identified and experimentally validated. The results may provide the basis for the design of a process to produce a sulforaphane-rich food supplement or nutraceutical by using a GRAS extractant.  相似文献   

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17.
The composition of the various groups of liposoluble compounds in the leaves of wild cabbage of early-, middle-, and late-ripening varieties have been identified and their amounts have been determined by chromatographic and chemical methods. About 30 groups of lipid substances have been identified, among which free and esterified forms of sterols, di- and triacylglycerols, hydrocarbons, lipoquinones, mono- and digalactoside glycerides, cerebrosides, phosphatidylethanolamines, phosphatidylglycerols, and phosphatidylcholines predominate. The presence of 13 components has been established among the fatty acids, linolenic acid being present in the greatest amount (50%). The influence of the time of ripening of the cabbage variety (early-, middle-, or late-ripening) on the composition of the lipid complex has been elucidated.M. V. Lomonosov Technological Institute of the Food Industry, Odessa. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 180–185, March–April, 1989.  相似文献   

18.
Profound research has been done on the medicinal value of Brassica nigra (BN) seeds, and the leaves of the plant have been investigated in this study. The methanol extracts of the leaves were subjected to several in?vitro studies. The antioxidant activity of methanol extract was demonstrated with a wide range of concentration, 10-500?μg?mL(-1), and the antioxidant activity increased with the increase in concentration. Total phenol content was found to be 171.73?±?5.043 gallic acid equivalents and the total flavonoid content 7.45?±?0.0945 quercetin equivalents. Further quantification and identification of the compounds were done by HPTLC and GC-MS analyses. The predominant phenolic compounds determined by HPTLC were gallic acid, followed by quercetin, ferulic acid, caffeic acid and rutin. The free radical quenching property of BN leaf extract suggests the presence of bioactive natural compounds.  相似文献   

19.
Nutraceuticals and functional foods are gaining more attention amongst consumers interested in nutritious food. The consumption of foodstuffs with a high content of phytochemicals has been proven to provide various health benefits. The application of biostimulants is a potential strategy to fortify cultivated plants with beneficial bioactive compounds. Nevertheless, it has not yet been established whether the proposed higher plants (St. John’s wort, giant goldenrod, common dandelion, red clover, nettle, and valerian) are appropriate for the production of potential bio-products enhancing the nutritional value of white cabbage. Therefore, this research examines the impact of botanical extracts on the growth and nutritional quality of cabbage grown under field conditions. Two extraction methods were used for the production of water-based bio-products, namely: ultrasound-assisted extraction and mechanical homogenisation. Bio-products were applied as foliar sprays to evaluate their impact on total yield, dry weight, photosynthetic pigments, polyphenols, antioxidant activity, vitamin C, nitrates, micro- and macroelements, volatile compounds, fatty acids, sterols, and sugars. Botanical extracts showed different effects on the examined parameters. The best results in terms of physiological and biochemical properties of cabbage were obtained for extracts from common dandelion, valerian, nettle, and giant goldenrod. When enriched with nutrients, vegetables can constitute a valuable component of functional food.  相似文献   

20.
Since biological activity of medicinal plants is dependent on cultivation area, climatic conditions, developmental stage, genetic modifications and other factors, it is important to study flora present in different growing sites and geographical zones. This study was focused on screening of antioxidant activity of C. angustifolium harvested in six different locations in Lithuania. The total contents of phenolic compounds, flavonoids and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were evaluated by spectrophotometric methods. A correlation between radical scavenging activity and total phenolic compounds content was observed (correlation coefficient 0.98). HPLC with online post-column DPPH radical scavenging reaction detection was used for the separation of extracts. Oenothein B, rutin and one unidentified compound were predominant. Volatile compounds were analysed using solid-phase microextraction coupled with gas chromatography–mass spectrometry. Based on the analysis of volatiles, all samples were classified into two chemotypes: (I) with predominant α- and β-caryophyllenes and (II) with predominant anethole.  相似文献   

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