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61.
Two pigmented wheat genotypes (blue and purple) and two black barley genotypes were fractionated in bran and flour fractions, examined, and compared for their free radical scavenging properties against 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (Trolox equivalent antioxidant capacity, TEAC), ferric reducing antioxidant power (FRAP), total phenolic content (TPC), phenolic acid composition, carotenoid composition, and total anthocyanin content. The results showed that fractionation has a significant influence on the antioxidant properties, TPC, anthocyanin and carotenoid contents, and phenolic acid composition. Bran fractions had the greatest antioxidant activities (1.9-2.3 mmol TEAC/100 g) in all four grain genotypes and were 3-5-fold higher than the respective flour fractions (0.4-0.7 mmol TEAC/100 g). Ferulic acid was the predominant phenolic acid in wheat genotypes (bran fractions) while p-coumaric acid was the predominant phenolic acid in the bran fractions of barley genotypes. High-performance liquid chromatography analysis detected the presence of lutein and zeaxanthin in all fractions with different distribution patterns within the genotypes. The highest contents of anthocyanins were found in the middlings of black barley genotypes or in the shorts of blue and purple wheat. These data suggest the possibility to improve the antioxidant release from cereal-based food through selection of postharvest treatments.  相似文献   
62.

Purpose  

The transfer of soil sediments and phosphorus from terrestrial to aquatic systems is a common process in agricultural lands. The aims of this paper are to quantify the soil phosphorus availability and to characterize phosphorus forms in soil sediments as contaminant agents of waters as a function of anthropic pressures.  相似文献   
63.
Purpose

The use of eco-friendly and cost-effective adsorbent materials in the remediation of soils contaminated by potentially toxic elements (PTE) is a sustainable way of reducing the transfer of these elements into the food chain. However, an evaluation of the potential of natural zeolites to immobilize toxic elements in contaminated soils was required to enable their efficient use.

Materials and methods

The effect of natural zeolite (Stilbite-Stellerite) from the Munella area (Northern Albania), added at rates ranging from 1.25 to 10 % w/w on a contaminated soil was investigated in a greenhouse pot experiment with ryegrass (Lolium multiflorum L.) and by selective extractions. PTE availability for plants was assessed either as their accumulation in plant tissue or by DTPA-extraction. Oral bio-accessibility was estimated by the in vitro PBET method and the mobility and consequent potential risk of leaching by the USEPA TLCP method. The effect of zeolites on soil properties (pH, electrical conductivity-EC, organic C, and total N) was also investigated. A five steps sequential extraction procedure (SEP) was applied to investigate the immobilization mechanism.

Results and discussion

The addition of 2.5% w/w of natural zeolites caused a significant decrease of PTE mobility, but to observe a significant reduction of DTPA-extractable metals, it was necessary to reach 10% addition rate. In contrast, plant growth showed a gradual increase with addition rate and a corresponding decrease of concentration of PTE in plant tissue. Correlation between DTPA-extractable PTE and their concentration in both root and shoot plant tissue was rather poor. Human hazard due to soil ingestion (PBET method) changed only for Cu and Zn in the gastric phase with 1.25 and 5% addition rate respectively, whereas decreased for Cu and Zn at 5% rate in the Intestinal phase. The results of SEP support the hypothesis that the main mechanism involved in metals fixation are as follows: (1) insolubilization by pH rise, (2) adsorption on Fe/Mn oxides (3) increase of cation exchange retention, (4) organic complexation.

Conclusions

The results of this work suggest that the addition of natural zeolites from the Munella area (AL) is a sustainable practice to reduce the environmental impact of PTE contaminated soils, but an assessment on the longevity of their immobilization need to be evaluated in the long-term perspectives.

  相似文献   
64.
A peroxidase antiperoxidase technique was used to identify alpha 2-macroglobulin in formalin-fixed sections of normal equine lung and liver and in tissue sections and bronchoalveolar lavage fluid from horses with various lung diseases. Equine peripheral blood leucocytes and bronchoalveolar lavage samples from clinically normal horses were negative for alpha 2-macroglobulin. It was concluded that liver and pulmonary macrophages may be potential sources of alpha 2-macroglobulin. Although alpha 2-macroglobulin may play a role in various chronic bronchointerstitial pneumonias of the horse, it is doubtful that it is of importance in equine chronic small airway disease.  相似文献   
65.
66.
Anoplocephala perfoliata (Cestoda, Cyclophyllidea), the commonest intestinal tapeworm of horses, can cause colic, intussusceptions, ileal impactions and intestinal perforations. Common diagnostic techniques for A. perfoliata infection, i.e. coprology and serology, show inherent limitations in terms of sensitivity and specificity and new approaches are thus required. Hence, the present study compared the reliability of coprological, serological (i.e. ELISA) and molecular (i.e. nested PCR) methods in detecting A. perfoliata infection in naturally infected horses and in horses treated with a combination of ivermectin and praziquantel. Of 42 horses subjected to coprological examination, 16 and 26 resulted negative and positive, respectively for the presence of A. perfoliata eggs at the coprological examination. The 26 coprologically positive animals were also positive by nested PCR. Fifteen out of the 16 horses coprologically negative were negative at the molecular assay, while one yielded a PCR product detectable on an agarose gel. Eighteen out of 26 positive horses were treated with a combination of ivermectin 18.7 mg/g and praziquantel 140.3mg/g and resulted subsequently negative by coprology and nested PCR performed 2 weeks after treatment. All infected and untreated animals had a high ELISA test optical density indicating high infection intensity and associated risk of colic. However, high optical density values were also obtained in four horses post-treatment and in three horses that were negative on molecular and coprological analysis. The results of the present work indicate that the nested PCR assay represents a valid method for the specific molecular detection of A. perfoliata in faecal samples collected from naturally infected horses and may have advantages over coprological and serological approaches for diagnosing A. perfoliata infection.  相似文献   
67.
The wide diffusion of tropospheric ozone is a major environmental problem, in urban area as well as in rural and remote localities. Its increasing man-related levels are connected to severe impacts on human life and welfare, in terms of adverse health effects, damage to manufacts and injury to plants. Biological monitoring is a powerful tool for filling the gap between the causes and the effects of environmental toxins, as bioindication agents assess in an easy-to-detect fashion the effects of pollution on (selected) biota. A project was launched in 2012 to involve some 190 students (ages 11–16) from three schools in Central Italy in biodetection of ozone effects with the hypersensitive plant Nicotiana tabacum Bel-W3. The project also involved teachers and families of the pupils. Results implied the reading of 12,000 biological data (ozone injury on cotyledons) and were fortified by data captured by four automatic analyzers (1300 raw data of hourly means). Biological and chemical data compared favorably and were treated with geostatistical methods; results are exposed in the form of cartographic restitutions. Under the guidance of their teachers, the pupils had several opportunities to practice with many basic and applied study areas and disciplines and were initiated into the scientific method in a simple and absorbing manner. Though primarily an educational exercise, the survey provided sound research elements and the picture of pollution that emerged has increased the knowledge of air quality in the area. Biomonitoring is confirmed to be a powerful tool to involve young people in environmental topics.  相似文献   
68.
Aim of this study was to evaluate the total antioxidant activity (TAA) of extra virgin olive oil (EVOO) and the effect of heating on the alpha-tocopherol content and TAA in relation to the presence of polyphenols, heating time, and temperature. Experiments included the measurement by ABTS decolorization assay of antioxidant capacity of alpha-tocopherol and 14 simple phenolic compounds present in EVOO, either dissolved in ethanol or added to refined olive oil, and the evaluation of TAA, total phenols, and alpha-tocopherol of six commercial EVOO and three olive oils. Finally, four experimental oils were prepared from refined olive oil containing a fixed amount (300 ppm) of alpha-tocopherol and increasing amounts of polyphenols (25, 125, 225, and 326 ppm) extracted from EVOO. The thermal stability of experimental oils under domestic heating conditions (heating time from 30 to 120 min, heating temperature from 160 to 190 degrees C) was studied by evaluating the loss of alpha-tocopherol and TAA according to a Latin square design. Results indicate that TAA of commercial oils is mainly due to their phenol and alpha-tocopherol content. Heating experiments suggest that polyphenols from EVOO are effective stabilizers of alpha-tocopherol during olive oil heating, thus contributing to the nutritional value of cooked foods.  相似文献   
69.
A unique, record-breaking, killer heat wave occurred across several European countries during the first two weeks of August 2003. As weather conditions which characterize heat waves are highly conductive to tropospheric ozone formation and persistence, this is a contributing factor which should be regarded as a major stressor for biota. Hourly ozone means were captured between 1 and 15 August 2003 with automatic analysers in nine stations in Tuscany, distributed into six Districts. Compared to historical ozone reference climatology, daily maxima of 2003 were systematically higher by a factor of about 1.5, with differences which approached three times standard deviation. At the end of the period, cumulated ozone exposure over the threshold of 40 ppb (AOT40) was 4,750 ppb h in 2003, vs 2,200 ppb h of the historical series; such a difference was four times the standard deviation of the long-term series. Biological data are also enclosed in the present study, in the form of analysis of the ratio between above ground biomass produced by NC-S and NC-R clones of white clover when exposed to ambient air. Standardised samplings were performed on a monthly basis, and a significant difference between the two data sets was observed between summer 2003 and the historical series. The close correlation of high-ozone episode with increased temperature (as a consequence of increased solar radiation) suggests that, if climate change were to result in warmer summers in Europe, more frequent exceedances of dangerous ozone thresholds would be expected at the current emission levels.  相似文献   
70.
A screening of Pteridophytes growing on serpentine and metalliferous soils in Northern Italy was carried out to assess the ability of these plants to tolerate or accumulate trace elements of toxicological interest. Few data are available on metal tolerance/accumulation of terrestrial ferns growing in the Mediterranean region, and several species presented here have never been investigated for this purpose. The trace‐element composition (As, Cd, Cr, Cu, Fe, Ni, Pb, Zn) and P content of aerial parts of plants (12 fern and 2 horsetail species) and of their associated soils were measured. An analysis of the relationship between element concentrations in soil and in shoot revealed a significant correlation only for Zn (p < 0.05). Hierarchical cluster analysis based on element concentrations in plant aerial parts showed two outliers, viz. Equisetum ramosissimum Desf., showing the highest levels of Cr, Fe, Cu, Ni, and As, and Nephrolepis cordifolia C. Presl., showing the highest Pb value. The bioaccumulation factor exceeded 1 only for Cd in two species, Athyrium filix‐femina and Dryopteris filix‐mas. However, also in these cases the corresponding values of the metal in the shoots were below the thresholds for hyperaccumulators. The examined Pteridophytes seem to have developed their adaptation prevalently through mechanisms of tolerance based on metal exclusion. None of these plant species seem suitable for phytoextraction, but N. cordifolia, Pteridium aquilinum ssp. aquilinum, and E. ramosissimum have potential to be used for stabilization and restoration of soils rich in heavy metals.  相似文献   
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