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951.
Erika S. Santos Maria Manuela Abreu Maria João Batista M. Clara F. Magalhães Eliana Fernandes 《Journal of Soils and Sediments》2014,14(4):758-772
Purpose
This study aimed to compare the variation on the accumulation and translocation of potentially harmful chemical elements and nutrients (As, Ca, Cu, Fe, K, Mg, Mn, Ni, Pb and Zn) in Cistus ladanifer L. belonging to populations growing in different mine areas from the Portuguese Iberian Pyrite Belt (Brancanes, Caveira, Chança, Lousal, Neves Corvo, São Domingos). These mines are abandoned (except Neves Corvo that is still operating) and have different contamination levels.Materials and methods
Composite samples of soils (n?=?31), developed on different mine wastes and/or host rock, and C. ladanifer plants (roots and shoots) were collected in the mine areas. Soils were characterized for pH, NPK and organic C, by classical methodologies. Soils (total fraction—four acid digestion, and available fraction—extracted with aqueous solution of diluted organic acids, simulating rizosphere conditions) and plants (ashing followed by acid digestion) elemental concentrations were determined by ICP. Soil–plant transfer and translocation coefficients were calculated. Principal components analysis in both ways, the classical method and a second approach with adaptations used mostly in multivariate statistical processes control data, were done in order to compare the plants populations.Results and discussion
Soils had large heterogeneity in their characteristics. Caveira, Lousal, Neves Corvo and São Domingos soils showed the highest total concentrations of As, Cu, Pb and Zn. Independently of the mine, available fractions of elements were low. Intra- and inter-population variations in accumulation and translocation of elements were evaluated. Plants were not accumulators of the majority of the analysed elements. Nutrients were mainly translocated from roots to shoots, while trace elements were stored in roots (except in Neves Corvo for As and Pb, and São Domingos for As). Elements concentrations in plant populations from Lousal, Chança and São Domingos did not present much variation. Brancanes soils and plants presented strong differences compared to other areas.Conclusions
Cistus ladanifer plants are able to survive in mining areas with polymetallic contamination at different elements concentrations in total and available fraction. This species presented variations inter- and intra-populations in accumulation and translocation of chemical elements; however, all studied populations, except Brancanes, can belong to the same population cluster. 相似文献952.
Lynch-Stieglitz J Adkins JF Curry WB Dokken T Hall IR Herguera JC Hirschi JJ Ivanova EV Kissel C Marchal O Marchitto TM McCave IN McManus JF Mulitza S Ninnemann U Peeters F Yu EF Zahn R 《Science (New York, N.Y.)》2007,316(5821):66-69
The circulation of the deep Atlantic Ocean during the height of the last ice age appears to have been quite different from today. We review observations implying that Atlantic meridional overturning circulation during the Last Glacial Maximum was neither extremely sluggish nor an enhanced version of present-day circulation. The distribution of the decay products of uranium in sediments is consistent with a residence time for deep waters in the Atlantic only slightly greater than today. However, evidence from multiple water-mass tracers supports a different distribution of deep-water properties, including density, which is dynamically linked to circulation. 相似文献
953.
Kim DH Kim JH Bae SE Seo JH Oh TK Lee CH 《Journal of agricultural and food chemistry》2005,53(7):2541-2545
Pigment extracts from the root of Lithospermum erythrorhizon are used as natural red dyes, as well as basic drugs due to their numerous pharmacological activities. In recent years, the demand for such natural pigment materials has increased; however, in natural dye production, the pigment yield is strongly affected by the source of cultivation, extracting conditions, and solvents. Accordingly, this study proposes a method of enzymatic pigment production based on the introduction of hydrolytic enzymes prior to the usual extraction to avoid repeated pigment extraction. The matrix destruction in the epidermal layer of the root by the enzymes was found to improve the pigment extractability, that is, the increment of K(L), the mass transfer coefficient, representing the pigment mobility in the epidermal layer. The root tissue maceration by the hydrolytic enzymes was also measured to evaluate the pigment extractability, and a linear relationship was observed between the K(L) values and the tissue maceration up to the addition of 3000 units/g of xylanase, indicating that the enzymatic maceration proportionally increases the interfacial area between the pigment and the solvent. Bacillus sp. DX107 xylanase only served to increase the extractability of the pigment by loosening the root shell matrix, without affecting the contents and color properties of the pigment, as almost no difference was found in the color between the pigments extracted using xylanase and those extracted according to the traditional method. 相似文献
954.
Ahn HJ Jo C Lee JW Kim JH Kim KH Byun MW 《Journal of agricultural and food chemistry》2003,51(5):1249-1253
The present study was undertaken to evaluate the irradiation and modified atmosphere packaging effects on emulsion-type cooked pork sausage during storage for 4 weeks. CO(2) (100%), N(2) (100%), or 25% CO(2)/75% N(2) packaged sausage were irradiated at 0, 5, and 10 kGy, and residual nitrite, residual ascorbic acid, nitrosomyoglobin (NO-Mb), color values, and their correlation were observed. Irradiation significantly reduced the residual nitrite content and caused partial reduction of NO-Mb during storage. No difference was observed in ascorbic acid content by irradiation. Irradiation decreased the Hunter color a value of sausage. CO(2) or CO(2)/N(2) packaging were more effective for reducing residual nitrite and inhibiting the loss of the red color of sausage compared to N(2) packaging. Results indicated that the proper combination of irradiation and modified atmosphere packaging could reduce the residual nitrite in sausage with minimization of color change. 相似文献
955.
Hwang JW Park JS Jo EH Kim SJ Yoon BS Kim SH Lee YS Kang KS 《Journal of agricultural and food chemistry》2005,53(21):8205-8210
The cruciferous vegetables such as Chinese cabbages and broccoli are known to have anticancer phytochemicals, and the consumption of cruciferous vegetables has been proposed to protect against various cancers. The anticarcinogenic properties of some Chinese cabbage extracts and sulforaphane glucosinolate (SFN) were assessed by examining their ability to prevent the inhibition of gap junctional intercellular communication (GJIC) induced by hydrogen peroxide (H2O2) in WB-F344 normal rat liver epithelial cells. The cells were preincubated with Chinese cabbage extracts and SFN for 24 h followed by cotreatment with cells and H2O2 (750 microM) for 1 h. Chinese cabbage extracts and SFN prevented the inhibition of GJIC and phosphorylation of gap junction protein connexin43 (Cx43) by H2O2 treatment. Chinese cabbage extracts and SFN were able to prevent the inhibition of GJIC through the blocking of Cx43 phosphorylaton and inactivation of ERK 1/2 and p38 MAP kinase. The results suggest that cruciferous vegetables and their components, SFN, may exert the anticancer effect by targeting the GJIC as a functional dietary chemopreventive agent. 相似文献
956.
Braga ME Leal PF Carvalho JE Meireles MA 《Journal of agricultural and food chemistry》2003,51(22):6604-6611
Turmeric extracts were obtained from two lots of raw material (M and S) using various techniques: hydrodistillation, low pressure solvent extraction, Soxhlet, and supercritical extraction using carbon dioxide and cosolvents. The solvents and cosolvents tested were ethanol, isopropyl alcohol, and their mixture in equal proportions. The composition of the extracts was determined by gas chromatography-flame ionization detection (GC-FID) and UV. The largest yield (27%, weight) was obtained in the Soxhlet extraction (turmeric (S), ethanol = 1:100); the lowest yield was detected in the hydrodistillation process (2.1%). For the supercritical extraction, the best cosolvent was a mixture of ethanol and isopropyl alcohol. Sixty percent of the light fraction of the extracts consisted of ar-turmerone, (Z)-gamma-atlantone, and (E)-gamma-atlantone, except for the Soxhlet extracts (1:100, ethanol), for which only ar-turmeronol and (Z)-alpha-atlantone were detected. The maximum amount of curcuminoids (8.43%) was obtained using Soxhlet extraction (ethanol/isopropyl alcohol). The Soxhlet and low pressure extract exhibited the strongest antioxidant activities. 相似文献
957.
Jean-Marie Prosperi Eric Jenczewski Michel Angevain Joëlle Ronfort 《Genetic Resources and Crop Evolution》2006,53(4):843-856
One hundred and three natural populations of Medicago L. were collected in Spain, mainly from roadsides, non-irrigated or grazed lands. This germplasm was evaluated at Montpellier
(France) with control cultivars and Spanish landraces under completely random block design, replicated four times, and observed
for 64 qualitative or quantitative characters. Differences between natural populations and cultivated controls are highly
significant, but gene flow occurs between wild and cultivated compartment and hybrid populations were identified. On the basis
of multivariable analysis, the accessions were grouped into four clusters depending on their proximity with the cultivated
pool to facilitate their management and ex situ conservation. The relationship between environment of the site of collection and phenotypic characteristics of the natural
populations was also discussed. Different policies of conservation of these genetic resources are suggested to avoid their
disappearance even when they disappeared from the other regions of the western Mediterranean. Spanish wild pool of alfalfa,
also called ‘Mielga’, appears of great interest for the breeding of alfalfa because it contains a large diversity of characteristics
(prostrate habit, rhizomes) linked to tolerance to grazing or drought environment. With the need for more sustainable systems
in agriculture, the erosion of natural habitats and the necessity for rehabilitation of degraded ecosystems, the importance
of this wild pool is really inestimable. 相似文献
958.
Antiatherogenic effects of structured lipid containing conjugated linoleic acid in C57BL/6J mice 总被引:3,自引:0,他引:3
Conjugated linoleic acids (CLA) were enzymatically acidolyzed with olive oil to produce structured lipids (SL), and their antiatherosclerotic properties were investigated in C57BL/6J mice. Twenty-eight mice were divided into four groups and fed control diet or atherogenic diets supplemented with high cholesterol and high fat (HCHF) containing 5% of lard, olive oil, or SL based on control diet for 4 weeks. The supplementation of SL diet (0.6% CLA) significantly reduced the levels of serum total cholesterol and total triglyceride and increased high-density lipoprotein cholesterol level as compared to lard and olive oil diet groups (p < 0.05). The activity of liver acyl CoA:cholesterol acyltransferase (ACAT) of mice fed the SL diet was significantly lower than that of mice fed the lard or olive oil diet. A reduced formation of aortic fatty streak was observed in SL group. The extent of CLA incorporation depended on tissues or types of phospholipids. More CLA was incorporated in adipose tissue (1.85 mol %) than in the liver (0.33 mol %). Besides, more CLA was found in phosphatidylethanolamine (PE) (0.47 mol %) than in phosphatidylcholine (PC) (0.05 mol %) of hepatic phospholipids. Hepatic phospholipids (PC and PE) of mice fed the SL diet contained reduced contents of arachidonic and linoleic acid compared with mice fed the olive oil or lard diet. The present study suggests that SL could be considered as a functional oil for preventing risks of atheroscelerosis. 相似文献
959.
Rho MC Lee HS Lee SW Chang JS Kwon OE Chung MY Kim YK 《Journal of agricultural and food chemistry》2005,53(4):919-922
Acyl-CoA: cholesterol acyltransferase (ACAT), which plays a role in the absorption, storage, and production of cholesterol, has been explored as a potential target for pharmacological intervention of hyperlipidemia and atherosclerotic disease. In our search for ACAT inhibitors from natural sources, the petroleum ether extract of Panax ginseng showed moderate inhibition of ACAT enzyme from rat liver microsomes. Bioactivity-guided fractionations led to the isolation of one new polyacetylenic compound, (9R,10S)-epoxy-16-heptadecene-4, 6-diyne-3-one (1), in addition to the previously reported polyacetylenic compounds 2 and 3. Their chemical structures were elucidated on the basis of spectroscopic evidence (UV, IR, NMR, and MS). The compounds 1, 2, and 3 showed significant ACAT inhibition with IC(50) values of 35, 47, and 21 microM, respectively. 相似文献
960.