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11.
Passi S Ricci R Cataudella S Ferrante I De Simone F Rastrelli L 《Journal of agricultural and food chemistry》2004,52(9):2587-2592
The levels of hydrophilic, lipophilic, and enzymatic antioxidants, the oxidative damage to lipids and proteins, and the fatty acid patterns of triglyceride and phospholipid fractions were assayed in fresh muscle tissue of rainbow trouts (Oncorhynchus mykiss) and sea basses (Dicentrarchus labrax) during aging, to investigate the correlation between oxidative stress and aging processes in fish. The present studies suggests that lipid peroxidation and accumulation of oxidized proteins during in vivo aging are most likely to be linked with an age-dependent decline of lipophilic antioxidants (CoQH(2), CoQ, and vitamin E) and vitamin C contents in muscle tissue, whereas fish aging is not linked to a decline in antioxidant enzymes and reduced glutathione levels. Lipophilic antioxidant and vitamin C levels represent a reliable marker of oxidative stress during aging, and their determination might be useful for the assessment of fish age. 相似文献
12.
LoCascio RG Ninonuevo MR Freeman SL Sela DA Grimm R Lebrilla CB Mills DA German JB 《Journal of agricultural and food chemistry》2007,55(22):8914-8919
The molecular basis by which human breast milk supports the development of a protective intestinal microbiome in infants is unknown. After lactose and lipids, human milk oligosaccharides (HMOs) are quantitatively the third largest and most diverse component of breast milk. In this work, glycomic profiling of HMO consumption by bifidobacteria using Fourier transform ion cyclotron resonance mass spectrometry reveals that one species, Bifidobacterium longum biovar infantis ATCC 15697, an isolate from the infant gut, preferentially consumes small mass oligosaccharides, representing 63.9% of the total HMOs available. These HMOs were detected in human breast milk at the onset and constantly through the first month of lactation by use of high performance liquid chromatography-chip time-of-flight mass spectrometry. Further characterization revealed that strain ATCC 15697 possesses both fucosidase and sialidase activities not present in the other tested strains. This work provides evidence that these small mass HMOs are selectively metabolized by select bifidobacterial strains and represent a potential new class of bioactive molecules functioning as prebiotics to facilitate a protective gut colonization in breast-fed newborns. 相似文献
13.
Disentangling effects of habitat diversity and area on orthopteran species with contrasting mobility
Loss of semi-natural grasslands and reduction of habitat diversity are considered major potential threats to arthropod diversity in agricultural landscapes. The main aim of this study was to investigate how area and habitat diversity, mediated by shrub encroachment after grassland abandonment, affect species richness of orthopterans in island-like grasslands, and how contrasting mobility might alter species richness response to both factors. We selected 35 isolated patches in landscapes dominated by arable land (durum wheat) in order to obtain two statistically uncorrelated gradients: (i) one in habitat area ranging from 0.2 to 55 ha and (ii) one in habitat diversity ranging from patches dominated by one habitat (either open grasslands or shrublands) to patches with a mosaic of different habitats. Habitat loss due to land-use conversion into arable fields was associated with a substantial loss of species with a positive species-area relationship (SAR), with sedentary species having a steeper and stronger SAR than mobile species. Halting habitat loss is, therefore, needed to avoid further species extinctions. Shrub encroachment, triggered by abandonment, presented a hump-shaped relationship with habitat diversity. An increase in habitat diversity enhanced species richness irrespective of patch area and mobility. Maintaining or enhancing habitat diversity, by cutting or burning small sectors and by reintroducing extensive sheep grazing into abandoned grassland, are suggested as complementary strategies to mitigate further decline of orthopteran diversity in the remnant patches. This would be equally important in both small and large patches. 相似文献
14.
Irrigation effects on quality, phenolic composition, and selected volatiles of virgin olive oils cv. Leccino 总被引:1,自引:0,他引:1
Servili M Esposto S Lodolini E Selvaggini R Taticchi A Urbani S Montedoro G Serravalle M Gucci R 《Journal of agricultural and food chemistry》2007,55(16):6609-6618
Field-grown olive trees (Olea europaea L. cv. Leccino) were used over two growing seasons to determine the effect of deficit irrigation regimes on virgin olive oil (VOO) quality. Drip irrigation was managed to maintain a predawn leaf water potential (PLWP): (a) higher than -1.1 MPa (full irrigation: FI); (b) between -1.0 and -3.3 MPa (deficit irrigation: DI); (c) higher than -4.2 MPa (severe deficit irrigation: SI). The fruit yield and oil yield of DI trees were over 90% of those of FI treatments in both years, respectively, whereas yields of SI trees ranged from 61 to 76%. The irrigation regime had minor effects on the free acidity, peroxide value, and fatty acid composition of VOO. The concentrations of phenols and o-diphenols in VOO were negatively correlated with PLWP. The concentrations of the dialdehydic form of decarboxymethyl elenolic acid linked to (3,4-dihydroxyphenyl)ethanol (3,4-DHPEA-EDA), the isomer of the oleuropein aglycon (3,4-DHPEA-EA), and the dialdehydic form of decarboxymethyl elenolic acid linked to (p-hydroxyphenyl)ethanol (p-HPEA-EDA) were lower in FI than in SI treatments. The concentrations of lignans (+)-1-acetoxipinoresinol and (+)-1-pinoresinol were unaffected by the irrigation regime. The tree water status had a marked effect on the concentration of volatile compounds, such as the C(6)-saturated and unsaturated aldehydes, alcohols, and esters. 相似文献
15.
To verify the presence of glycolaldehyde in wine resulting from reduction of glyoxal after malolactic fermentation, sterilized solutions of synthetic cultures were inoculated with a lactic bacterium of the type Oenococcus oeni. Fermentation was also carried out on solutions with glyoxal added. The resulting glycolaldehyde concentrations turned out to be associated with the amounts of glyoxal present, and glyoxal was seen to decrease as glycolaldehyde increased. In addition, it was observed that glyoxal principally forms from breakdown of sugars and that reduction to glycolaldehyde is mainly promoted by bacterial activity. Finally, the ability of glycolaldehyde to induce browning of (+)-catechin in a model wine system was verified and turned out to be about 10 times higher than that of ascorbic acid. 相似文献
16.
M. Lodovica Gullino Riccardo Savigliano Giuliana Gasparrini Corrado Clini 《Phytoparasitica》2007,35(4):321-329
Methyl bromide (MB) was phased out on January 1, 2005, and a Critical Use Exemption (CUE) process has been established in
order to define the rules for allocating the needed amounts of the fumigant. This paper deals with the effects of the CUE
process on Italian horticulture. The actual usage of the amounts of MB allocated to Italy for the year 2005 in the different
areas and on the economically most important crops was monitored and critically evaluated. The usage pattern monitored shows
that already in the first year after MB phaseout, Italy was able to replace it completely on crops such as zucchini, salad
greens, basil and watermelon. However, on crops such as tomato, pepper, melon, eggplant, strawberry, and cut flowers, further
work is required in order fully to replace MB. The emerging problems and research needs are discussed briefly. 相似文献
17.
18.
V Furlanetto G Zagotto R Pasquale S Moro B Gatto 《Journal of agricultural and food chemistry》2012,60(36):9162-9170
Ellagic acid (EA), a natural polyphenol abundant in fruits and common in our diet, is under intense investigation for its chemopreventive activity resulting from multiple effects. EA inhibits topoisomerase II, but the effects on the human enzyme of urolithins, its monolactone metabolites, are not known. Therefore, the action of several synthetic urolithins toward topoisomerases II was evaluated, showing that polyhydroxylated urolithins, EA, and EA-related compounds are potent inhibitors of the α and β isoforms of human topoisomerase II at submicromolar concentrations. Competition tests demonstrate a dose-dependent relationship between ATP and the inhibition of the enzyme. Docking experiments show that the active compounds bind the ATP pocket of the human enzyme, thus supporting the hypothesis that EA and polyhydroxylated urolithins act as ATP-competitive inhibitors of human topoisomerase II. 相似文献
19.
Domenica Scuderi Cristina Restuccia Marco Chisari Riccardo N. Barbagallo Cinzia Caggia Francesco Giuffrida 《Postharvest Biology and Technology》2011,59(2):132-137
Quality, microbiological and enzymatic characteristics of fresh-cut lettuce (Lactuca sativa var. longifolia, ‘Duende’), grown in floating system with three electrical conductivities of nutrient solutions (2.8, 3.8 and 4.8 mS cm?1), were investigated in order to evaluate the effect of salinity on product shelf-life during cold storage (9 d at 4 °C). Pre-harvest salinity of 3.8 and 4.8 mS cm?1 improved the properties of fresh-cut lettuce, since CO2 production was reduced with a subsequent control of the decay process. Fresh-cut processing caused an activation of polyphenol oxidase and peroxidase; in all cases the product obtained by salinity treatments was less subject to oxidase activity and browning phenomena during storage. Increased salinity reduced the number of mesophilic bacteria and of moulds and yeasts, assessed by plate counts on different culture media; in contrast, Enterobacteriaceae levels were unaffected by pre-harvest treatments. The research demonstrated that an increase in nutrient solution electrical conductivity, through the use of floating system, affects fresh-cut lettuce characteristics, improving shelf-life of the product. 相似文献
20.
Bibring JP Langevin Y Mustard JF Poulet F Arvidson R Gendrin A Gondet B Mangold N Pinet P Forget F Berthé M Bibring JP Gendrin A Gomez C Gondet B Jouglet D Poulet F Soufflot A Vincendon M Combes M Drossart P Encrenaz T Fouchet T Merchiorri R Belluci G Altieri F Formisano V Capaccioni F Cerroni P Coradini A Fonti S Korablev O Kottsov V Ignatiev N Moroz V Titov D Zasova L Loiseau D Mangold N Pinet P Douté S Schmitt B Sotin C Hauber E Hoffmann H Jaumann R Keller U Arvidson R Mustard JF Duxbury T 《Science (New York, N.Y.)》2006,312(5772):400-404
Global mineralogical mapping of Mars by the Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activité (OMEGA) instrument on the European Space Agency's Mars Express spacecraft provides new information on Mars' geological and climatic history. Phyllosilicates formed by aqueous alteration very early in the planet's history (the "phyllocian" era) are found in the oldest terrains; sulfates were formed in a second era (the "theiikian" era) in an acidic environment. Beginning about 3.5 billion years ago, the last era (the "siderikian") is dominated by the formation of anhydrous ferric oxides in a slow superficial weathering, without liquid water playing a major role across the planet. 相似文献