Search results for "40"
showing 10 items of 17345 documents
Organic nitrogen steadily increasing in Norwegian rivers draining to the Skagerrak coast
2020
AbstractDeclining atmospheric nitrogen (N) deposition, through reduction in the direct input of inorganic N, may result in less inorganic N being leached from soils to freshwaters (dissolved inorganic N = DIN). Declining sulphur deposition, through reducing the ionic strength in soil water, increases the solubility and mobility of organic soil compounds and may result in increased leaching of organically bound N to freshwaters (total organic N = TON). It is unknown to which extent these two independents and opposing trends, i.e. DIN decline versus TON increase, may affect the nutrient balance (load, stoichiometry) of river water draining into coastal zones. By combining long-term atmospheri…
Grazing decreases N partitioning among coexisting plant species
2017
Herbivores play a key role in shaping ecosystem structure and functions by influencing plant and microbial community composition and nutrient cycling. This study investigated the long‐term effects of herbivores on plant resource acquisition. We explored differences in the natural δ15N signatures in plant, microbial and soil N pools, and examined mycorrhizal colonization in two tundra sites that have been either lightly or heavily grazed by reindeer for more than 50 years. The study examined changes in nutrient acquisition in five common tundra plants with contrasting traits and mycorrhiza status; the mycorrhizal dwarf shrubs, Betula nana, Vaccinium myrtillus and Empetrum hermaphroditum; a m…
Antifungal effect of phenolic extract of fermented rice bran with Rhizopus oryzae and its potential use in loaf bread shelf life extension
2018
In this study the antifungal potential of a phenolic extract obtained from rice bran fermented with Rhizopus oryzae CECT 7560 and its application in the elaboration of bread was assessed.; Results: Eighteen compounds with antifungal potential were identified by LC-ESI-qTOF-MS in the extract: organic acids, gallates and gallotannins, flavonoids, ellagic acid and benzophenone derivatives. The extract was active against strains of Fusarium, Aspergillus and Penicillium, with minimum inhibitory concentration ranging from 390 to 3100 µg mL-1 and minimum fungicidal concentration variable from 780 to 6300 µg mL-1 . The strains that were most sensitive to the phenolic extract were F. graminearum, F.…
No apparent effect of invasive alien goldenrod on soil microbial communities or soil fauna feeding activity
2020
Abstract Invasive alien species spreading in abandoned agricultural landscape may negatively affect native organisms, including plants and soil biota. This study assessed the effects of invasion by Solidago sp. (goldenrod) in southern Poland on soil fauna feeding activity and on soil microorganism activity, biomass, and functional and taxonomic diversity, in a comparisons of paired plots: goldenrod-invaded plots and nearby non-invaded plots of semi-natural grassland. Goldenrod-invaded plots had fewer vascular plant species (paired t-test) than non-invaded ones, and showed a distinct plant community composition (ANOSIM). Non-invaded and invaded plots did not differ in a range of measured soi…
Identification of New Odorous Heterocyclic Compounds in French Blue Cheeses
2000
International audience
Toward a better understanding of fish‐based contribution to ocean carbon flux
2021
Fishes are the dominant vertebrates in the ocean, yet we know little of their contribution to carbon export flux at regional to global scales. We synthesize the existing information on fish-based carbon flux in coastal and pelagic waters, identify gaps and challenges in measuring this flux and approaches to address them, and recommend research priorities. Based on our synthesis of passive (fecal pellet sinking) and active (migratory) flux of fishes, we estimated that fishes contribute an average (± standard deviation) of about 16.1% (± 13%) to total carbon flux out of the euphotic zone. Using the mean value of model-generated global carbon flux estimates, this equates to an annual flux of 1…
Development of a Bioactive Sauce Based on Oriental Mustard Flour with Antifungal Properties for Pita Bread Shelf Life Improvement
2019
Ochratoxin A (OTA) is a mycotoxin produced in the secondary metabolism of fungus belonging to the genus Aspergillus and Penicillium. In this study, the employment of oriental mustard flour (OMF) as an ingredient in a packaged sauce was evaluated for the generation in situ of the antimicrobial compound allyl isothiocyanate (AITC) in order to preserve pita bread contaminated with Penicillium verrucosum VTT D-01847, an OTA producer, in an active packaging system. Four different concentrations (8, 16, 33 and 50 mg/g) were tested. Mycelium formation, mycotoxin production, AITC absorbed by the food matrix, and volatilization kinetics were studied for each concentration. The results obtained were …
Antifungal and antimycotoxigenic activity of allyl isothiocyanate on barley under different storage conditions
2019
Abstract The present study evaluated the efficacy of allyl isothiocyanate (AITC) in avoiding the growth of Penicillium verrucosum and consequent ochratoxin A (OTA) production in barley during storage for 90 d. Environmental humidity was controlled using saturated salt solutions and moisture content (MC) of the grain was analyzed. Moreover, the residual concentration of AITC on stored barley was also examined. Samples with 20.6% of MC presented the highest absorption of AITC with levels ranging from 75 to 4 mg/kg at day 1 and 90, respectively. The population of P. verrucosum was significantly reduced after 24 h of AITC exposure. After 90 d, the non-treated control group reached a fungal popu…
Efficiency of Ohmic assisted hydrodistillation for the extraction of essential oil from oregano (Origanum vulgare subsp. viride) spices
2017
Abstract The aim of this work was to investigate the effects of Ohmic heating-assisted hydrodistillation (OAHD), applied at different voltages (100, 150, and 200) V, on the qualitative and quantitative characteristics of extracted essential oil from oregano herb ( Origanum vulgare subsp. viride ), compared to a conventional hydrodistillation (HD) procedure. The compositions of the extracted essential oils (using OAHD and HD) were assessed using gas chromatography - mass spectrometry (GC–MS). A 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH) method was applied in order to evaluate antioxidant activity. The antimicrobial activity as well as the minimum inhibitory concentration (MIC) values …
Potential of an exploitation of acid-tolerant antimicrobial microorganisms evolving enzyme systems for the utilization of dairy by-products and ligno…
2016
Introduction Bioproduction of optically pure lactic acid (LA) has roused interest in the recent years due to its potential application in a wide range of fields, and there is a significant interest to further development of sustainable and cost-effective process. However, the efficient utilization of agro-industrial wastes for LA production still causes considerable challenges. The biotechnological LA production within the targeted cost still required the development of high-performance LA-producing microorganisms and the lowering of the costs of raw materials and fermentation process. Cheap biomass, such as starchy and cellulosic agricultural residues or by-products from the food industry,…