Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2016
Forfattere
A. Lagomarsino A. E. Agnelli R. Pastorelli G. Pallara Daniel Rasse Hanna Marika SilvennoinenSammendrag
The water management system of cultivated paddy rice soils is one of the most important factors affecting the respective magnitudes of CH4 and N2O emissions. We hypothesized an effect of past management on soil microbial communities and greenhouse gas (GHG) production potential. The ob- jectives of this study were to i) assess the influence of water management history on GHG production and microbial community structure, ii) relate GHG production to the microbial communities involved in CH4 and N2O production inhabiting the different soils. Moreover, the influence of different soil condi- tioning procedures on GHG production was determined. To reach these aims, we compared four soils with different water management history, using dried and sieved, pre-incubated and fresh soils. Soil conditioning procedures strongly affected GHG production: drying and sieving induced the highest production rates and the largest differences among soil types, probably through the release of labile substrates. Conversely, soil pre-incubation tended to homogenize and level out the differences among soils. The water management history strongly affected microbial community structure, which was itself tightly linked to CH4 and N2O production. N2O production was the highest in aerobic soil, which also exhibited the strongest evidence for active nitrifying communities (NirK). Drying and rewetting aerobic soil enhanced the production of nitrate, which was further reduced to N2O through denitrification. As expected, CH4 production was the lowest in aerobic soil, which showed a less abundant archaeal com- munity. This work supports the hypothesis that microbial communities in paddy soils progressively adapt to water management practices, thereby reinforcing potential differences in GHGs production.
Sammendrag
There is limited knowledge on the toxicological, physiological, and molecular effects attributed to organophosphate (OP) compounds currently used as flame retardants or additives in consumer products. This study investigated the effects on oxidative stress and lipid peroxidation in juvenile Atlantic salmon liver and brain samples after exposure to two OP compounds, tris(2-butoxyethyl) phosphate (TBOEP) and tris(2-chloroethyl) phosphate (TCEP). In this study, groups of juvenile Atlantic salmon were exposed using a semistatic experimental protocol over a 7-d period to 3 different concentrations (0.04, 0.2, or 1 mg/L) of TBOEP and TCEP. When toxicological factors such as bioaccumulation and bioconcentration, and chemical structural characteristics and behavior, including absorption to solid materials, are considered, these concentrations represent environmentally relevant concentrations. The concentrations of the contaminants were derived from levels of their environmental occurrence. The expression of genes related to oxidative stress—glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST)—and to lipid peroxidation—peroxisome proliferator-activated receptors (PPAR)—were determined using quantitative (real-time) polymerase chain reaction (PCR). The presence of PPAR proteins was also investigated using immunochemical methods. Levels of thiobarbituric acid-reactive substances (TBARS) in liver were used as a measure of lipid peroxidation. Overall, our data show an increase in lipid peroxidation, and this was associated with an augmented expression of genes from the glutathione family of responses. Interestingly, PPAR expression in liver after exposure to TBOEP and TCEP was consistently decreased compared to controls, while expression in brain did not show a similar trend. The results suggest that OP contaminants may induce oxidative stress and thus production of reactive oxygen substances (ROS), and modulate lipid peroxidation processes in organisms.
Sammendrag
Wood protection against fungal decay is mainly based on chemical protection. Nontoxic protection methods have become more important in Europe due to environmental concerns. A method using electric fields to inhibit wood decay by fungi has been investigated in laboratory trials and wood mass loss and moisture content after exposure to fungal attack were determined. The results show significantly reduced mass loss for wood samples exposed to a low pulsed electric field (LPEF), while wood samples connected to alternating and direct current displayed higher mass loss compared to LPEF. Changing the electrode material reduced the mass increase due to metal ion transfer into the wood samples for LPEF-exposed samples. The use of conductive polymer instead of metal electrodes and carbon fibers was preferable as no ions were transferred and the integrity of the material persisted. Decay of pre-exposed wood samples to white rot could be stopped or slowed down by means of LPEF.
Forfattere
Augustine Arukwe Camilla Catarci Carteney Monica Möder Alberto Bonini Morten Andre Maubach Trine EggenSammendrag
Following the ban of polybrominated diphenyl ether (PBDEs) flame retardants under well-documented toxicity issues, organophosphate such as tris(2-butoxyethyl) phosphate (TBOEP) and tris(2-cloroethyl) phosphate (TCEP) were considered as potential substitutes. Although TBOEP and TCEP are consistently detected in the aquatic environment, there are few data about the possible toxicological effects of these compounds on aquatic organisms, including fish. In the present study, we have investigated the influence of TBOEP and TCEP on neuro- and interrenal steroidogenesis of juvenile Atlantic salmon (Salmo salar), after a seven-day exposure to four different concentrations (0 (control), 0.04, 0.2 and 1 mg/L) of each compound. TBOEP and TCEP were diluted in Milli-Q water. The expression of genes involved in ster- oidogenesis (StAR, cyp19a, cyp19b, cholesterol side-chain cleavage enzyme (P450scc), 3β-hydroxysteroid dehydrogenase (3β-hsd), and 11β-hydroxylase (cyp11β)), were analyzed in the brain and head kidney using real-time PCR. Plasma 11-ketotestosterone (11-KT) analysis was performed using enzyme im- munoassay (EIA). Our results showed that TBOEP accumulated more rapidly than TCEP in fish muscle tissue. Surprisingly, TBOEP produced less pronounced effects than TCEP on neural and interrenal ster- oidogenic responses, despite the observed rapid uptake and bioaccumulation pattern. Specifically, TBOEP produced significant and consistent concentration-specific alterations on neural- and interrenal ster- oidogenesis. Plasma levels of 11-KT were not significantly altered by any of the exposures. The increased expression of steroidogenic genes demonstrated in the present study could produce time-specific al- terations in the production of glucocorticoids and steroid hormones that play integral roles in fish me- tabolism, stress responses and adaptation, sexual maturation, reproduction and migration with overt consequences on reproductive success and survival.
Forfattere
Elli Aurora Koskela Anita Sønsteby Henryk Flachowsky Ola M. Heide Magda-Viola Hanke Paula Elomaa Timo HytönenSammendrag
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Sammendrag
Det er ikke registrert sammendrag
Forfattere
Eva Brod Anne K. Falk Øgaard Tore Krogstad Trond Haraldsen Emmanuel Frossard Astrid ObersonSammendrag
Det er ikke registrert sammendrag
Forfattere
Robert Nemeth Callum Aidan Stephen Hill Peter Takats Laszlo TolvajSammendrag
Black locust, poplar and spruce samples were steamed at 80°C and 120°C for 48 hours. IR difference spectra and the CIE Lab colour coordinates were measured for determining the chemical changes caused by the steaming. Steaming at 80°C caused only small changes in both IR spectra and colour. But steaming at 120°C produced intensive colour change and well-visible changes in IR spectra. The guaiacyl lignin in hardwoods underwent slight degradation but in spruce suffered substantial degradation during steaming at 120°C. The syringyl lignin absorbing around 1600 cm−1 did not show any changes, indicating that it is more stable to steaming than guaiacyl lignin. The absorption decrease at 1175 cm−1 indicated the cleavage of ether linkage in cellulose and hemicelluloses at both steaming temperatures.
Sammendrag
Schistidium marginale is described as a new species from several European states including Austria, Georgia, Italy, Macedonia, Spain, Switzerland and Turkey. The species is fully illustrated, its affinities are discussed in detail and its current distribution is mapped. The new species is closely related to S. confertum and S. echinatum from which it differs in having a coarser and thicker costa which is 3–4-stratose in mid-leaf and 4-layered at the base; strongly thickened, 2–4-stratose and (1–)2–5-seriate leaf margins; and a thicker and stiffer leaf hair-point. It clearly belongs to Schistidium Bruch & Schimp. sect. Conferta (Vilh.) Ochyra on account of the distinct 3–6(–7)-seriate basal marginal border of quadrate to short-rectangular, often subhyaline cells with distinctly thickened transverse walls.
Forfattere
Martina Jonsson Marika Jestoi Minna Anthoni Annikki Welling Iida Loivamaa Ville Hallikainen Matti Kankainen Erik Lysøe Pertti Koivisto Kimmo PeltonenSammendrag
The mycotoxin enniatin B, a cyclic hexadepsipeptide produced by the plant pathogen Fusarium, is prevalent in grains and grain-based products in different geographical areas. Although enniatins have not been associated with toxic outbreaks, they have caused toxicity in vitro in several cell lines. In this study, the cytotoxic effects of enniatin B were assessed in relation to cellular energy metabolism, cell proliferation, and the induction of apoptosis in Balb 3T3 and HepG2 cells. The mechanism of toxicity was examined by means of whole genome expression profiling of exposed rat primary hepatocytes. Enniatin B altered cellular energy metabolism and reduced cell proliferation in Balb 3T3 and HepG2 cell lines. Furthermore, the proportion of apoptotic cell populations of Balb 3T3 cells slightly increased. On the other hand, enniatin B caused necrotic cell death in primary hepatocytes. Gene expression studies revealed the alteration of energy metabolism due to effects on mitochondrial organization and function and the assembly of complex I of the electron transport chain.