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81.
The aim of this research was to evaluate the suitability of uracil as an hygienic quality index of tomato products. Whereas uridine was naturally present throughout tomato fruits' ripening, uracil appeared only after microbial contamination. In tomato pulp inoculated with nine different microbial strains, all five lactic acid bacteria (LAB) studied released relevant quantities of uracil (150-1040 mg/kg of dm), with a correlated partial or total decrease of uridine. Uracil production by yeasts and molds was very low or nonexistent; the starting uridine concentration (approximately 960 mg/kg of dm) remained constant or increased. Uracil thermostability was also verified. Twenty-six samples of tomato paste (30 degrees Brix) were collected from bag-in-drums produced in an industrial processing plant, some with evident swelling symptoms. All of the samples with high microbial count presented uracil. Uracil was also present in samples with microbial contamination under the detection limit and Howard mold count below legislation limits, implying the reprocessing, at least partial, of altered tomato product. The results indicate that uracil presence in tomato products is an index of LAB contamination that has occurred before heat treatment. 相似文献
82.
Decaro N Mari V Lucente MS Sciarretta R Moreno A Armenise C Losurdo M Camero M Lorusso E Cordioli P Buonavoglia C 《Veterinary microbiology》2012,155(2-4):165-171
To date, limited information is available on the ability of 'Hobi'-like pestiviruses (putative bovine viral diarrhoea 3) to infect and cause disease in animal species traditionally affected by pestiviruses. In order to obtain new insights into host range and pathogenic potential of this atypical pestivirus, BVDV-seronegative calves (n=5), lambs (n=5) and piglets (n=5) were experimentally infected with the European 'Hobi'-like strain Italy-1/10-1, whereas two animals per species served as uninfected controls. Appearance of clinical signs, leukopenia, viremia, viral shedding and seroconversion were monitored for 28 days post-infection. Calves and lambs were successfully infected, displaying respiratory signs (nasal discharge), moderate hyperthermia and leukopenia, viremia and viral shedding through the nasal and faecal routes. Antibody responses were observed in both animal species by ELISA and virus neutralisation assays. In contrast, inoculated piglets did not display any clinical signs nor leukopenia and viral RNA was not detected in any biological samples. Nevertheless, the presence of detectable antibodies by virus neutralisation accounted for a successful, albeit limited infection of these animals. 相似文献
83.
Cooper J Sanderson R Cakmak I Ozturk L Shotton P Carmichael A Haghighi RS Tetard-Jones C Volakakis N Eyre M Leifert C 《Journal of agricultural and food chemistry》2011,59(9):4715-4724
The effects of organic versus conventional crop management practices (crop rotation, crop protection, and fertility management strategies) on wheat yields and grain metal (Al, Cd, Cu, Ni, Pb, and Zn) concentrations were investigated in a long-term field trial. The interactions between crop management practices and the season that the crop was grown were investigated using univariate and redundancy analysis approaches. Grain yields were highest where conventional fertility management and crop protection practices were used, but growing wheat after a previous crop of grass/clover was shown to partially compensate for yield reductions due to the use of organic fertility management. All metals except for Pb were significantly affected by crop management practices and the year that the wheat was grown. Grain Cd and Cu levels were higher on average when conventional fertility management practices were used. Al and Cu were higher on average when conventional crop protection practices were used. The results demonstrate that there is potential to manage metal concentrations in the diet by adopting specific crop management practices shown to affect crop uptake of metals. 相似文献
84.
Adsorption and desorption of triasulfuron by soil 总被引:10,自引:0,他引:10
Pusino A Fiori MG Braschi I Gessa C 《Journal of agricultural and food chemistry》2003,51(18):5350-5354
The adsorption and desorption of the herbicide triasulfuron [2-(2-chloroethoxy)-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide] by three soils, soil organic matter (H(+) and Ca(2+)-saturated), and an amorphous iron oxide were studied. Adsorption isotherms conformed to the Freundlich equation. It was found that pH is the main factor influencing the adsorption in all of the systems. Indeed, the adsorption on soils was negatively correlated with pH. The highest level of adsorption was measured on soils with low pH and high organic carbon content. Moreover, it was found that humic acid is more effective in the adsorption compared with calcium humate (the pH values of the suspensions being 3.5 and 6, respectively). Experiments on amorphous iron oxide confirmed the pH dependence. Desorption was hysteretic on soils having high organic carbon content. 相似文献
85.
Carlo C. Lazado Christopher Marlowe A. Caipang Sanchala Gallage Monica F. Brinchmann Viswanath Kiron 《Fish physiology and biochemistry》2010,36(4):883-891
This study identified phytase-producing bacteria that were previously isolated from the gastrointestinal tract of Atlantic
cod, Gadus morhua and determined its effect on head kidney leukocytes. Out of the 216 bacterial strains tested, the two phytase producers were
identified as Pseudomonas sp. and Psychrobacter sp. based on their 16S rDNA sequence. Crude phytase from these two bacterial strains was produced employing the shake flask
method. Even though the total protein of the crude phytase was not significantly different for the two bacteria, the phytase
activity of the crude enzyme produced by Pseudomonas sp. (97.1 ± 16.7 U) was significantly higher than that of the enzyme from Psychrobacter sp. (75.9 ± 2.4 U). When cod head kidney leukocytes were incubated with the crude phytase (50 μg ml−1), it resulted in enhanced cell proliferation, higher myeloperoxidase, and acid phosphatase activities. Extracellular responses—respiratory
burst activity and hydrogen peroxide production were not enhanced by the crude enzyme. As a consequence, the growth of two
pathogenic bacteria Aeromonas salmonicida and Vibrio anguillarum was not suppressed by the supernatants obtained from head kidney leukocytes incubated with the crude bacterial phytase. Thus,
the enzyme from phytase-producing intestinal bacteria of Atlantic cod can stimulate intracellular head kidney leukocyte activities
but not the production of extracellular substances that are involved in antibacterial response. These have implications on
the potential use of bacterial phytase as feed supplement to boost cellular immune response of the fish and could be employed
as a health management strategy in culture systems. 相似文献
86.
Monica Montefalcone Giancarlo Albertelli Carlo Nike Bianchi Mauro Mariani Carla Morri 《水产资源保护:海洋与淡水生态系统》2006,16(1):29-42
- 1. The status of a Posidonia oceanica meadow in front of the town of Sanremo, Italy, was studied through a combined use of benthic mapping and synthetic indices.
- 2. Mapping was accomplished by integrating side scan sonar imagery and data collected by scuba diving along transects placed perpendicularly to the coastline. A thematic map (scale 1:5000) was produced. Extent of the meadow, occurrence of dead matte areas, and morphology of the lower limit (with new definition) are all described.
- 3. Two synthetic environmental indices were applied to transect data in order to quantify the status of the meadow: the Conservation Index and the Substitution Index. The former is related to the proportion of dead matte; the latter is a novel index measuring the amount of replacement of the ‘constructional’ seagrass P. oceanica by the ‘non‐constructional’ seagrass Cymodocea nodosa. The potential of a ‘phase shift’ in Ligurian Sea seagrass meadows is discussed.
- 4. The approach here proposed, based on detailed mapping plus synthetic indices, may provide immediate information to evaluate the state of Mediterranean Posidonia oceanica for monitoring and management.
87.
Triglycerides from Urena lobata 总被引:1,自引:0,他引:1
Two triglycerides, both bearing polyunsaturated fatty acid residues, were isolated from the hexane extract of Urena lobata. One of them is characterized by the presence of three different polyunsaturated fatty acids. Their structures were studied with spectral methods. 相似文献
88.
Chiara Bertora Francesco Alluvione Laura Zavattaro Jan Willem van Groenigen Gerard Velthof Carlo Grignani 《Soil biology & biochemistry》2008,40(8):1999-2006
The treatment of manures may improve their agricultural value and environmental quality, for instance with regards to greenhouse gases mitigation and enhancement of carbon (C) sequestration. The present study verified whether different pig slurry treatments (i.e. solid/liquid separation and anaerobic digestion) changed slurry composition. The effect of the slurry composition on N2O and CO2 emissions, denitrification and soil mineral nitrogen (N), after soil incorporation, was also examined during a 58-day mesocosm study. The treatments included a non-treated pig slurry (NT), the solid fraction (SF), and the liquid fraction (LF) of a pig slurry and the anaerobically digested liquid fraction (DG). Finally, a non-fertilized (N0) and a treatment with urea (UR) were also present.The N2O emissions measured represented 4.8%, 2.6%, 1.8%, 1.0% and 0.9% of N supplied with slurry/fertilizer for NT, LF, DG, SF and UR, respectively. Cumulative CO2 emissions ranged from 0.40 g CO2-C kg?1 soil (0.38 Mg CO2-C ha?1) to 0.80 g CO2-C kg?1 soil (0.75 Mg CO2-C ha?1). They were highest for SF (56% of C applied), followed by NT (189% of C applied), LF (337% of C applied) and DG (321% of C applied). Ammonium was detected in the soil for all treatments only at day one, while nitrate concentration increased linearly from day 15 to day 58, at a rate independent of the type of slurry/fertilizer applied. The nitrate recovery at day 58 was 39% of the N applied for NT, 19% for SF, 52% for LF, 67% for DG, and 41% for UR. The solid fraction generally produced higher potential denitrification fluxes (75.3 for SF, 56.7 for NT, 53.6 for LF, 47.7 for DG and 39.7 mg N2O + N2-N kg?1 soil for UR). The high variability of actual denitrification results obfuscated any treatment effect.We conclude that treatment strongly affects slurry composition (mainly its C, fibre and NH4+ content), and hence N2O and CO2 emission patterns as well as denitrification processes and nitrate availability. In particular, the solid fraction obtained after mechanical separation produced the most pronounced difference, while the liquid fraction and the anaerobically digested liquid fraction did not show significant difference with respect to the original slurry for any of the measured parameters. Combining data from the different fractions we showed that separation of slurry leads to reduced N2O emissions, irrespective of whether the liquid fraction is digested or not. Furthermore, our results suggested that the default emission factor for N2O emissions inventory is too low for both the non-treated pig slurry and its liquid fraction (digested or not), and too high for the separated solid fraction and urea. 相似文献
89.
Sarah Giovanna Montenegro Lima Marjorie Caroline Liberato Cavalcanti Freire Vernica da Silva Oliveira Carlo Solisio Attilio Converti dley Antonini Neves de Lima 《Marine drugs》2021,19(9)
Astaxanthin (AST) is a biomolecule known for its powerful antioxidant effect, which is considered of great importance in biochemical research and has great potential for application in cosmetics, as well as food products that are beneficial to human health and medicines. Unfortunately, its poor solubility in water, chemical instability, and low oral bioavailability make its applications in the cosmetic and pharmaceutical field a major challenge for the development of new products. To favor the search for alternatives to enhance and make possible the use of AST in formulations, this article aimed to review the scientific data on its application in delivery systems. The search was made in databases without time restriction, using keywords such as astaxanthin, delivery systems, skin, cosmetic, topical, and dermal. All delivery systems found, such as liposomes, particulate systems, inclusion complexes, emulsions, and films, presented peculiar advantages able to enhance AST properties, among which are stability, antioxidant potential, biological activities, and drug release. This survey showed that further studies are needed for the industrial development of new AST-containing cosmetics and topical formulations. 相似文献
90.