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51.
In the present study the phenolic composition of leaves, stalks, and textile fiber extracts from Urtica dioica L. is described. Taking into account the increasing demand for textile products made from natural fibers and the necessity to create sustainable "local" processing chains, an Italian project was funded to evaluate the cultivation of nettle fibers in the region of Tuscany. The leaves of two nettle samples, cultivated and wild (C and W), contain large amounts of chlorogenic and 2- O-caffeoylmalic acid, which represent 71.5 and 76.5% of total phenolics, respectively. Flavonoids are the main class in the stalks: 54.4% of total phenolics in C and 31.2% in W samples. Anthocyanins are second in quantitative importance and are present only in nettle stalks: 28.6% of total phenolics in C and 24.4% in W extracts. Characterization of phenolic compounds in nettle extracts is an important result with regard to the biological properties (antioxidant and antiradical) of these metabolites for their possible applications in various industrial activities, such as food/feed, cosmetics, phytomedicine, and textiles.  相似文献   
52.
In order to provide values of key parameters in aquaculture waste degradation modelling specifically for the Mediterranean, sampling campaigns were carried out in 2006. Accurate measurements of particulate carbon input and benthic respiration rates were performed using sediment traps and intact core incubations. The in situ measurements, compared with data from Atlantic salmon production, showed lower carbon flux and oxygen consumption, while a greater degradation capability was observed. Moreover, a temperature dependence of the benthic parameters was highlighted. Successively, the model Finite Organic Accumulation Module was used for an accurate comparison between different parameterizations. Finite Organic Accumulation Module simulates the organic carbon degradation and the net carbon accumulation on the sediment, yielding a benthic state index. In comparison with previous results, there was a decrease in benthic impacts due to minor inputs of carbon and higher mineralization rates. Moreover, a seasonal variation could be observed in the organic carbon concentration. Nevertheless, the new results remain consistent with the old ones on two points: (a) the negligible benthic impact of faeces with respect to uneaten feed and (b) the dependence of that impact on the different feed release conditions.  相似文献   
53.
Tropical Animal Health and Production - Small ruminant lentiviruses (SRLVs) are a heterogeneous group of viruses of sheep, goat, and wild ruminants responsible of lifelong persistent infection...  相似文献   
54.
Blueberries ( Vaccinium corymbosum L.) are rich sources of phenolics and anthocyanins (ACNs). We investigated the absorption of ACNs after consumption of one portion (300 g) of minimally processed blueberry purée (P) obtained from blanched (BL) or unblanched (NB) berries. A repeated-measures, crossover design study was conducted on healthy human volunteers. Blood was drawn between baseline and 24 h after BL-P or NB-P consumption, while urine were collected from the day before the experiment up to 48 h. Total plasma ACN content was not significantly different, while phenolics content was higher in BL-P with respect to NB-P. The maximum ACN absorption in plasma was observed after 1.5 h from the intake of the purées and was significantly higher (p ≤ 0.05) after the intake of BL-P. Both products increased the excretion of hippuric acid in urine. In conclusion, blanching had no significant effect on total ACN content and enhanced their absorption from minimally processed purées.  相似文献   
55.
The aim of this study was to evaluate if the exposure to Avian metapneumovirus (aMPV) and/or to Turkey hemorrhagic enteritis virus (THEV) was significant for the induction of episodes of colibacillosis in aMPV and THEV vaccinated turkeys. Colibacillosis-associated mortality was recorded and longitudinal virological studies performed in three consecutive turkey flocks reared in the same farm. aMPV and THEV diagnostic swabs and blood samples were made once a week up to 14 weeks of age. Swabs were processed by molecular techniques for viruses detection and antibody titres were evaluated. Field subtype B aMPVs were detected in all flocks at different ages of life always associated with respiratory signs and increase of colibacillosis-associated mortality. THEV has been consistently detected in all flocks since the 9th week of age. Vaccination with a single dose of the THEV commercial inactivated vaccine available in Italy seems does not protect the birds from the infection. Sequence comparison of the hexon protein of one of the THEV strains detected, and strains isolated worldwide, revealed high similarity between them. These results are consistent with the notion that the hexon protein, being the major antigenic component of the virus, is highly conserved between the strains. Results showed that field aMPV infection is directly correlated to colibacillosis-associated mortality. Less clear appears the role of THEV because the endemicity of aMPV makes difficult to evaluate its role in predisposing colibacillosis in absence of aMPV. It would be interesting to further investigate this issue through experimental trials in secure isolation conditions.  相似文献   
56.
Giant fennel (Ferula communis L.) from Sardinia is characterized by two chemotypes with different biological activities. One chemotype is poisonous, due to prenylcoumarins, and responsible for ferulosis, which mainly affects sheep and goats, cattle, and horses; the other chemotype is nonpoisonous and contains daucane esters. The two chemotypes cannot be distinguished botanically. High-performance liquid chromatography-diode array-ultraviolet detection-mass spectrometry (HPLC-DAD-UV-MS) analysis of the composition of the fractions containing the biologically active metabolites and of the volatile fractions, by gas chromatography-mass spectrometry (GC-MS), of both essential oil and headspace sampled by headspace solid-phase microextraction (HS-SPME) are here shown to be effective in discriminating the poisonous and nonpoisonous chemotypes. HS-SPME with CAR/PDMS/DVB in combination with GC-MS has also been found to be a successful, fully automated one-step method for rapid and unequivocal discrimination of the two chemotypes, using aristolene and allohedycaryol as markers of the poisonous and nonpoisonous chemotypes, respectively.  相似文献   
57.
The geological record of ocean acidification   总被引:1,自引:0,他引:1  
Ocean acidification may have severe consequences for marine ecosystems; however, assessing its future impact is difficult because laboratory experiments and field observations are limited by their reduced ecologic complexity and sample period, respectively. In contrast, the geological record contains long-term evidence for a variety of global environmental perturbations, including ocean acidification plus their associated biotic responses. We review events exhibiting evidence for elevated atmospheric CO(2), global warming, and ocean acidification over the past ~300 million years of Earth's history, some with contemporaneous extinction or evolutionary turnover among marine calcifiers. Although similarities exist, no past event perfectly parallels future projections in terms of disrupting the balance of ocean carbonate chemistry-a consequence of the unprecedented rapidity of CO(2) release currently taking place.  相似文献   
58.
The levels of hydrophilic, lipophilic, and enzymatic antioxidants, as well as the fatty acids composition, of triglyceride and phospholipid fractions were determined in the muscle tissue of 21 species of teleosts, 3 species of cephalopods, and 6 species of crustaceans, just caught from the central Tyrrhenian Sea (Mediterranean Sea). The enzymatic activities and the levels of low-molecular-weight antioxidants, and the percentages of fatty acids, showed marked interspecies differences. Our results showed that total polyunsaturated fatty acids (21.7-61.5%) were the highest, followed by saturated (16.9-41.3%) and monounsaturated (9.1-42.8%) fatty acids. The total n-3 fatty acids content (16.6-57.1%) was found to be higher than the total n-6 fatty acids content (4.1-10.6%). All of the species studied had an n-3/n-6 ratio of more than 1, confirming the great importance of fish and shellfish as a significant dietary source of n-3 polyunsaturated fatty acids and their beneficial role in the Mediterranean type of diet.  相似文献   
59.
Stir bar sorptive extraction (SBSE) in combination with GC-ECD/FPD analysis is here applied to the determination of the residues of 11 pesticides (hexachlorobenzene, lindane, chlorothalonil, parathion methyl, parathion ethyl, fenitrothion, malathion, dieldrin, alpha- and beta-endosulfan, and tetradifon) in herbal teas prepared with Passiflora alata Dryander spiked leaves. The method was optimized using spiked herbal teas in a range from 0.05 to 1 pg/microL for organochlorine pesticides and from 0.15 to 3 pg/microL for organophosphorus pesticides. The method is reproducible and repeatable with recoveries calculated from herbal teas prepared with spiked plant material versus spiked herbal teas, varying from about 30% for tetradifon to about 90% for parathion methyl and malathion. The limits of quantitation (LOQs) ranged from 0.017 pg/microL for lindane to 0.117 pg/microL for malathion.  相似文献   
60.
The average content of some classes of antioxidants is generally higher in cherry tomatoes than in normal-sized berries. The aim of this work was to assess the nutritional value of cherry tomato (cv. Naomi F1) by investigating the compositional pattern of berries harvested at different ripening stages and evaluating, in particular, all of the main antioxidants (carotenoids, ascorbic acid, phenolic compounds, and alpha-tocopherol) and the antioxidant activity of the water-soluble and water-insoluble fractions. Results confirmed the relatively high level of carotenoids in cherry tomato but showed that not all biologically active compounds necessarily increase in tomatoes picked at later stages of ripeness. Cherry tomatoes harvested at full ripeness exhibited the highest level of carotenoids and antioxidant activity in the water-insoluble fraction. On the other hand, no significant differences in ascorbic acid content were observed at different ripening stages, whereas the main phenolics content and the antioxidant activity of water-soluble fraction showed slight, but significant, decreases at later stages of ripeness.  相似文献   
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