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31.
Antioxidant activity of anthocyanins and their aglycons 总被引:13,自引:0,他引:13
The antioxidant activity of the six common anthocyanidins, pelargonidin, cyanidin, delphinidin, peonidin, petunidin, and malvidin, and their glycosidic forms was evaluated in three lipid-containing models [human low-density lipoprotein (LDL) and bulk and emulsified methyl linoleate]. In addition, the radical scavenging activity of the compounds against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical was studied. Most anthocyanins and their aglycons acted as strong antioxidants in emulsion and LDL. Many compounds showed an activity comparable to the well-known antioxidants alpha-tocopherol, Trolox, catechin, and quercetin. In bulk methyl linoleate, anthocyanins and anthocyanidins possessed only a weak antioxidant activity or even oxidation-promoting activity. Depending on the anthocyanidin, different glycosylation patterns either enhanced or diminished the antioxidant power. For the most part, the activities of the glycosides and the aglycons did not differ remarkably in emulsion. In LDL the aglycons showed in general higher activities than the glycosides. In bulk oil, to the contrary, the glycosides were more effective than the aglycons. 相似文献
32.
33.
Montealegre C Marina ML García-Ruiz C 《Journal of agricultural and food chemistry》2010,58(22):11808-11813
A simple extraction method was developed to extract proteins from olive samples based on chloroform/methanol extraction followed by a protein precipitation with cold acetone. Then, a capillary electrophoresis (CE) method was carried out using an acid buffer (1 M formic acid at pH 2) to ensure a positive net charge for proteins and a neutral charge for potential interferents as polyphenols. The method developed was applied to raw and table olive samples. Interestingly, raw olive samples showed differences in protein profiles depending upon the botanical variety of olives and their geographical region. Protein profiles obtained for table olives also showed differences according to the sample treatment. Thus, a signal reduction in the electropherograms obtained for black olives was observed in comparison to those achieved for treated green olives. In this work, the use of protein profiles was demonstrated to be a powerful tool for studying variations among olive samples. 相似文献
34.
Jaime Villaverde Roda Posada-Baquero Marina Rubio-Bellido Esmeralda Morillo 《Journal of Soils and Sediments》2013,13(6):1075-1083
Purpose
The herbicide diuron has the unfortunate property of being strongly adsorbed onto soil organic matter particles, and hence, is slowly degraded in the environment because of its reduced bioavailability. The aim of this work was to gain insight into the fate and behaviour of diuron in the soil–water system, and develop and test an environmentally friendly soil decontamination technique that could give rise to an enhancement of diuron mineralisation by sensitive soil endogenous microorganisms, by means of increasing the bioavailability of the pollutant employing cyclodextrin (CD) solutions what would represent an improvement from both economic and environmental standpoints.Materials and methods
Selected soil colloidal components: montmorillonite, a synthetic humic acid and a synthetic acicular goethite, and two different soils were employed in this study to perform batch adsorption–desorption experiments. Desorption experiments were performed using a 0.01 M Ca(NO3)2 solution with and without hydroxypropyl-β-cyclodextrin (HPBCD) 50 mM. Assays to study the mineralisation of 14C-labelled diuron were performed in respirometers, into which 10 g of soil and 50 mL of mineral salts medium (MMK) were placed, obtaining a final concentration of 50 mg?kg?1 and a radioactivity of approximately 900 Bq per flask.Results and discussion
Humic acid could be clearly discerned as the major colloidal component responsible for adsorption. HPBCD was used in diuron desorption experiments from soil, showing a strong extracting power on its removal. The mineralisation of diuron in the presence and absence of HPBCD was tested in a soil managed with diuron for several years, involving therefore the presence of microorganisms that have some specificity for diuron. Natural soil attenuation for diuron was improved when a HPBCD solution was used in the presence of micronutrients as a bioavailability enhancer, obtaining 66 % of mineralisation in comparison to that obtained with only micronutrients addition (44 %).Conclusions
The use of HPBCD solution at a very low concentration of only 10 times the diuron equimolar concentration in soil, acts as a bioavailability enhancer, accelerating the passage of the diuron-desorbing fraction from the soil particle surface to the soil solution, and hence, improving the accessibility of the microorganisms to the herbicide. Diuron mineralisation rate and the extent of its mineralisation were improved when the HPBCD solution was employed in the presence of micronutrients. 相似文献35.
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37.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.38.
Markus Euring Jerzy Trojanowski Marina Horstmann Alireza Kharazipour 《Wood Science and Technology》2012,46(4):699-708
In this work, the results of the enzymatic oxidation of TMP-fibers (thermomechanical pulp) and a well-structured lignin model compound, the dehydropolymer (DHP), were investigated by different 14C and 13C methods, caused by a Laccase–Mediator-System (LMS). These methods are the nuclear magnetic resonance spectroscopy (13C-NMR) with DHP (unmarked) and the determination of the 14CO2 release of 14C-marked DHP and TMP-fibers. The 13C-NMR measurements were chosen to analyze the structural changes of the LMS-treated DHP model compounds and TMP-fibers qualitatively and quantitatively. The data of 14CO2 release give an explanation of the demethylation of DHP and TMP-fibers. The effect of the LMS is shown by comparing the results in respect of DHP and TMP-fibers, which were only treated with laccase and of an inactivated LMS as the control. Comparing the results of the 13C-NMR method, in particular the use of the Mediator during the enzymatical treatment, showed significant changes in the structure of the DHP. Also, the TMP-fibers were materially influenced by the LMS. The analysis of the 14CO2 release data of the 14C-marked DHP and TMP-fibers revealed that the rate of 14CO2 increases in the 14C-2 atom as well as in the O14CH3 group within the first hour of Laccase–Mediator incubation. Therefore, the 14CO2 release from the DHP was higher than from the TMP-fibers. 相似文献
39.
A new iridoid diglucoside, 10-O-(E)-p-coumaroylmelittoside (1) and a new flavone glucoside, O-(6'-O-Acetyl-)-beta-glucopyranosylchrysoeriol (2), together with four known flavone glycosides, were isolated from the aerial parts of Sideritis lanata. The structures of the new compounds were elucidated by spectroscopic methods, 2D NMR and MS. 相似文献
40.
Kovacevic Branislav Roncevic Savo Miladinovic Dragana Ivanisevic Petar Katanic Marina 《New Forests》2009,38(2):177-185
The relationship between early root and shoot formation at the beginning of the vegetation period and cutting survival on
sandy and loamy fluvisol for 14 genotypes of black poplars was analyzed. Considerable cutting mortality was observed only
within the first 80 days since planting. Intensive root formation in the first 20 days since the planting and vigorous shoot
growth and development in subsequent 20 days was observed in easy-to-root genotypes. Coefficients of correlation revealed
close relationship between early root and shoot growth and development and cutting survival of tested genotypes. The obtained
results could be used in the breeding process, as well as for the design of cultivar-adjusted nursery and plantation establishment
technology. Tested shoot characteristics, were found to be especially interesting since they could be measured rapidly, by
non-destructive means. 相似文献