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541.
Curcio M Puoci F Cirillo G Iemma F Spizzirri UG Picci N 《Journal of agricultural and food chemistry》2010,58(22):11883-11887
A molecularly imprinted polymer able to recognize melamine in partially aqueous medium was synthesized using methacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross-linking agent. The bound specificity and selectivity of the obtained material were verified by performing binding experiments with melamine and its structural analogue, 2,4,6-trimethoxy-1,3,5-triazine, respectively, using different aqueous binding media. Finally, the ability of MIP to selectively extract melamine from two real samples, a food supplement and a freeze-dried meat sample, was demonstrated. 相似文献
542.
Evidente A Cabras A Maddau L Marras F Andolfi A Melck D Motta A 《Journal of agricultural and food chemistry》2006,54(18):6588-6592
A new pentasubstituted oxiranyldecene, named viridenepoxydiol, has been isolated (0.9 mg/L) from the culture filtrate of a strain of Trichoderma viride showing in vitro and in vivo antagonistic activity against Sclerotium rolfsii, which is the causal agent of crown and stem rot of artichoke. Viridenepoxydiol was characterized as 3,5,9-trimethyl-2-oxiranyl-dec-8-ene-2,5-diol (3) using spectroscopic methods. It showed inhibitor effect on mycelial growth of S. rolfsii and its minimum inhibitory concentration (over 90% inhibition) was found to be 396 mug/mL. This is the first time that viridenepoxydiol was reported. 相似文献
543.
Lo Cantore P Iacobellis NS De Marco A Capasso F Senatore F 《Journal of agricultural and food chemistry》2004,52(26):7862-7866
Essential oils were extracted from the fruits of Coriandrum sativum L. and Foeniculum vulgare Miller var. vulgare (Miller) and assayed in vitro for antibacterial activity to Escherichia coli and Bacillus megaterium, bacteria routinely used for comparison in the antimicrobial assays, and 27 phytopathogenic bacterial species and two mycopathogenic ones responsible for cultivated mushroom diseases. A significant antibacterial activity, as determined with the agar diffusion method, was shown by C. sativum essential oil whereas a much reduced effect was observed for F. vulgare var. vulgare oil. C. sativum and F. vulgare var. vulgare essential oils may be useful natural bactericides for the control of bacterial diseases of plants and for seed treatment, in particular, in organic agriculture. The significant antibacterial activity of essential oils to the bacterial pathogens of mushrooms appears promising. 相似文献
544.
Fogassi L Ferrari PF Gesierich B Rozzi S Chersi F Rizzolatti G 《Science (New York, N.Y.)》2005,308(5722):662-667
Inferior parietal lobule (IPL) neurons were studied when monkeys performed motor acts embedded in different actions and when they observed similar acts done by an experimenter. Most motor IPL neurons coding a specific act (e.g., grasping) showed markedly different activations when this act was part of different actions (e.g., for eating or for placing). Many motor IPL neurons also discharged during the observation of acts done by others. Most responded differentially when the same observed act was embedded in a specific action. These neurons fired during the observation of an act, before the beginning of the subsequent acts specifying the action. Thus, these neurons not only code the observed motor act but also allow the observer to understand the agent's intentions. 相似文献
545.
Luigi d'Aquino Massimo Morgana Michele Staiano Marilena Re Francesco Vinale Sheridan L. Woo 《Soil biology & biochemistry》2009,41(12):2406-2413
Accumulation of rare earth elements (REE) in the soil may be due to the use of REE enriched fertilizers and to contamination by REE containing wastes. Although widely used in China for soil and foliar dressing of crops, little is known about the effect of REE applications on the soil microbial community. The effect of REE on the growth of biological control strains of Trichoderma atroviride and Trichoderma harzianum was investigated in vitro using either a mix of different REE containing different amounts of lanthanum, cerium, praseodymium, neodymium, gadolinium nitrate and lanthanum nitrate alone in comparison to treatments with potassium nitrate and water. In plate tests applied concentrations ranged from 0.1 mM to 300 mM for lanthanum and REE mix and from 0.1 mM to 900 mM for the potassium solution. In liquid culture tests applied concentrations ranged from 0.001 mM to 100 mM for lanthanum and REE mix and from 0.003 mM to 900 mM for the potassium solution. ICP-MS, TEM and TEM X-ray microanalysis were used to study the accumulation of REE in fungal biomass. All the Trichoderma strains showed a good tolerance to the presence of REE in the culture media. Some growth enhancing effects were observed in liquid cultures of T. harzianum strains but not in T. atroviride. Accumulation of REE in fungal biomass, both at intracellular level and in the extracellular matrix, was observed. 相似文献
546.
Recent observations and general circulation models indicate that future temperature changes linked to global warming might be characterized by a marked asymmetry between daytime maxima and nighttime minima. We investigate the importance of such a pattern in determining future wheat (Triticum aestivum) yields in the Central United States by using a dynamic crop growth model, CERES-Wheat, modified to include physiological effects of temperature and CO2 on canopy photosynthesis. Simulations are run at four sites spanning a north-south transect of the Central US; four mean temperatures increases (1–4°C) are applied to baseline daily climate data (1951–1980). The effects of two different scenarios of temperature change (minimum and maximum temperatures equally raised; minima increased three times as much as maxima in agreement with recent observations) are analyzed under both current (330 ppm) and elevated (550 ppm) CO2 concentrations. The main mechanisms controlling the simulated wheat responses are direct and indirect temperature effects on wheat phenological development. Negative effects of temperature on simulated wheat yields are reduced when minima increase more than maxima. Yield changes are consistently negative under temperature change and current COZ concentration, while they range from positive to negative under temperature change and elevated COZ concentration. Responses vary across the transect, with larger negative effects occurring at the southernmost site. 相似文献
547.
Massimiliano Renna Maria Gonnella Sofia Caretto Giovanni Mita Francesco Serio 《Genetic Resources and Crop Evolution》2017,64(1):205-216
Sea fennel (Crithmum maritimum L.) is a perennial halophyte species typical of coastal ecosystems, used fresh in traditional cuisine and folk medicine due to its sensory properties and a good content of healthy compounds. Although considered as a promising biosaline crop, this halophyte is underutilized for commercial cultivation possibly due to a shortage of its consumer demand. For promoting a full exploitation of this species, a new food product was obtained by drying sea fennel using different treatments (air-drying, microwave-drying, microwave-assisted air-drying and freeze-drying). Water activity, essential oil content, chlorophylls, surface colour, colouring power and sensory evaluation were analyzed. All drying treatments allow to obtain a good water activity but significantly reduced the content of essential oils and chlorophylls. Freeze-drying and microwaving preserved the surface colour parameters more than other drying treatments, while freeze-drying gave the product the best colouring power. Based on sensory analysis, microwave-drying, microwave-assisted air-drying and freeze-drying showed the highest scores among the drying methods. Taken together the results indicate that microwaving and freeze-drying are optimal for preserving qualitative traits, including organoleptic properties, in dried sea fennel for food use. Furthermore, dried sea fennel can be usefully exploited in human food not only for its aromatic traits but also for its food colouring power like other plant derived natural colorants. It could be concluded that this underutilized crop could play a better role for making up a sustainable food production system. 相似文献
548.
Francesco Vinale Krishnapillai Sivasithamparam Emilio L. Ghisalberti Roberta Marra Sheridan L. Woo Matteo Lorito 《Soil biology & biochemistry》2008,40(1):1-10
Biological control involves the use of beneficial organisms, their genes, and/or products, such as metabolites, that reduce the negative effects of plant pathogens and promote positive responses by the plant. Disease suppression, as mediated by biocontrol agents, is the consequence of the interactions between the plant, pathogens, and the microbial community. Antagonists belonging to the genus Trichoderma are among the most commonly isolated soil fungi. Due to their ability to protect plants and contain pathogen populations under different soil conditions, these fungi have been widely studied and commercially marketed as biopesticides, biofertilizers and soil amendments. Trichoderma spp. also produce numerous biologically active compounds, including cell wall degrading enzymes, and secondary metabolites. Studies of the three-way relationship established with Trichoderma, the plant and the pathogen are aimed at unravelling the mechanisms involved in partner recognition and the cross-talk used to maintain the beneficial association between the fungal antagonist and the plant. Several strategies have been used to identify the molecular factors involved in this complex tripartite interaction including genomics, proteomics and, more recently, metabolomics, in order to enhance our understanding. This review presents recent advances and findings regarding the biocontrol-resulting events that take place during the Trichoderma–plant–pathogen interaction. We focus our attention on the biological aspects of this topic, highlighting the novel findings concerning the role of Trichoderma in disease suppression. A better understanding of these factors is expected to enhance not only the rapid identification of effective strains and their applications but also indicate the potentials for improvement of natural strains of Trichoderma. 相似文献
549.
Saba A Mazzini F Raffaelli A Mattei A Salvadori P 《Journal of agricultural and food chemistry》2005,53(12):4867-4872
The olive oil market is suffering from sophisticated illegal treatments. One common adulteration process consists of the addition to virgin olive oil of lower quality oils, such as "lampante" oil, an inexpensive oil and with some organoleptic defects, which is then submitted to thermal deodorization under vacuum processes for removal of the undesired flavor components. Such a blending may not have a huge influence on the chemical composition and may not significantly affect the parameters usually checked as quality indicators, although the organoleptic properties may change. As a consequence, a major effort is being devoted to find reliable markers able to unmask such adulterations. We report here the complete characterization of a compound, detected at trace levels exclusively in thermal stressed oils, which could be a candidate marker for adulteration. The investigation, carried out by GC-MS and GC-MS/MS, provided its complete structure, including the stereochemistry, shown to be a 9(E),11(E)-18:2 fatty acid methyl ester. Experimental data also confirmed the influence of both temperature and heating time on formation and concentration of this compound. 相似文献
550.
Pietro Zito Francesca Serraino Francesco Carimi Francesca Tavella Maurizio Sajeva 《Genetic Resources and Crop Evolution》2018,65(5):1329-1335
The wild grapevine [Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi] is the Eurasian dioecious ancestral form of mostly monoecious domesticated cultivars (Vitis vinifera subsp. vinifera). There are different hypotheses about grapevine pollination, varying from insect to wind pollination to spontaneous self-pollination. The aim of this paper is to update our knowledge on the biology of the wild grapevine by studying the insects visiting their inflorescences. During the fieldworks, floral visitors were observed, captured and identified. The most frequent insects visiting both sexes of wild grapevine were beetles (55%) followed by bees (45%). The present study shows that although in vineyards the wind may play a role in the cross-pollination, insects can contribute to the reproductive success of the wild grapevine. The knowledge of inflorescence-visiting insects, which potentially can act as pollinators may represent an important contribution to the conservation perspective of wild grapevine. 相似文献