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.
2023
Forfattere
Mathias Amundsen Laura Jaakola Kjersti Aaby Inger Martinussen N. Kelanne S. Tuominen O. Laaksonen B. Yang Anne Linn HykkerudSammendrag
Lingonberries (Vaccinium vitis-idaea L.) from two locations, northern (69°N, 18°E) and southern (59°N, 10°E) Norway, were grown under controlled conditions in a phytotron at two temperatures (9 and 15 °C) to study the effects of the ripening temperature and origin on the chemical composition of the berries. The concentrations of phenolic compounds, sugars, and organic acids as well as the profile of volatile organic compounds (VOCs) were determined using chromatographic and mass spectrometric methods. Five anthocyanins, eleven flavonols, eight cinnamic acid derivatives, three flavan-3-ols, three sugars, three organic acids, and 77 VOCs were identified, of which 40 VOCs had not previously been reported in lingonberries. Berries from both locations, were found to have higher contents of anthocyanins and cinnamic acid derivatives when ripened at lower temperature (9 °C), compared to the higher temperature (15 °C). Lingonberries of northern origin had a different VOC profile and higher contents of anthocyanins and organic acids than berries originating from the south. Lingonberries from the northern location also had higher proportions of cyanidin-3-O-glucoside and cyanidin-3-O-arabinoside than lingonberries from the southern location. The results show that the composition of lingonberries is influenced by both the environment and the origin of the plants, with phenolic compounds mainly influenced by the growth temperature and VOCs mainly influenced by plant origin.
Forfattere
Mathias Amundsen Kjersti Aaby Laura Jaakola Gesine Schmidt Inger Martinussen Anne Linn HykkerudSammendrag
Lingonberries (Vaccinium vitis-idaea L.) have received much positive attention due to their exotic taste and high phenolic content. These small red fruits grow across Norway, a country with large variations in abiotic and biotic growth conditions. The large variations in abiotic and biotic growth conditions have potential to influence quality and availability of lingonberries. A three-year study (2019-2021) with 64 field plots across Norway have therefore been set up, with the aim of studying the effect of climate and growth conditions on lingonberries. Here, anthocyanin content in berries from the first growth season is presented. Eight locations across Norway (58 to 69°N) with supposed high production potential of lingonberries were selected. Within each location, eight stands (250 m2) with different biotic conditions were chosen. Berries from each sector were lyophilised and extracted with 70% methanol. Phenolic compounds were analysed by HPLC-DAD-MSn, with quantification of anthocyanin at 520 nm and MS used for identification. The three major anthocyanins in Norwegian lingonberries were cyanidin-3-galactoside (69-90%), -arabinoside (6-23%) and -glucoside (2-10%). Additionally, small quantities of three other cyanidin glycosides were preliminarily identified. The total content of anthocyanins in lingonberries ranged from approximately 320 to 790 mg 100 g‑1 dw. There appears to be a variation in anthocyanin concentration linked to latitude. However, as the variation was as large within the stands of each location as they were between the locations, different growth factors would also play key parts in synthesis of anthocyanins in lingonberries. Results from analysis of berries collected in 2020 and 2021 are necessary to have the basis to draw a conclusion on how biotic and abiotic factors influence anthocyanin content of lingonberries.
Forfattere
Mathias Amundsen Laura Elina Jaakola Kjersti Aaby Gesine Schmidt Inger Martinussen Anne Linn HykkerudSammendrag
Lingonberry is an evergreen dwarf shrub abundant in the area of Nordic countries and a food traditionally regarded as a staple of Nordic diets. There is however limited commercial harvest of these readily available berries. The objective of this doctoral thesis is to investigate how the composition Norwegian lingonberries vary and is affected by abiotic and biotic growth conditions. The thesis consists of four papers of which three studies were conducted in controlled conditions investigating the effects of ripening, light conditions, and temperature during ripening on the composition of the targeted compounds in lingonberries. The fourth paper of the thesis investigates the variation in composition of wild Norwegian lingonberries and how different environmental factors influence this composition. In lingonberries, in total 29 phenolic compounds, sucrose, glucose and fructose as well as 4 organic acids and 77 volatile organic compounds were detected.. In the controlled studies time of harvest significantly influenced the quality of the lingonberries. Spectral light composition with supplemental blue wavelengths increased the content of anthocyanins, and slightly influenced the ratio of sugars to organic acids. There was only a limited effect of light intensity on the content of anthocyanins in lingonberries. Berries grown at lower temperatures had a higher content of anthocyanins and organic acids, whereas the other phenolic compounds were not significantly influenced. Latitude and temperature had the most significant effect on the content of anthocyanins in lingonberries. While light conditions only slightly influence berry quality, factors such as amount of precipitation during ripening, the density of deciduous trees, and altitude also significantly influenced berry quality. Precipitation influenced the content of organic acids in the field study. The result from this study further strengthens the evidence that lingonberries are a rich source for dietary polyphenols, and that berry quality increases with later harvest times. High quality lingonberries can be found across the country with large variation within local areas. The combination of field experiments and controlled experiments showed that weather conditions during ripening, latitude and density of deciduous trees all influence berry quality.
Sammendrag
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Sammendrag
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Sammendrag
Arctic ecosystems are increasingly exposed to extreme climatic events throughout the year, which can affect species performance. Cryptogams (bryophytes and lichens) provide important ecosystem services in polar ecosystems but may be physiologically affected or killed by extreme events. Through field and laboratory manipulations, we compared physiological responses of seven dominant sub-Arctic cryptogams (three bryophytes, four lichens) to single events and factorial combinations of mid-winter heatwave (6°C for 7 days), re-freezing, snow removal and summer nitrogen addition. We aimed to identify which mosses and lichens are vulnerable to these abiotic extremes and if combinations would exacerbate physiological responses. Combinations of extremes resulted in stronger species responses but included idiosyncratic species-specific responses. Species that remained dormant during winter (March), irrespective of extremes, showed little physiological response during summer (August). However, winter physiological activity, and response to winter extremes, was not consistently associated with summer physiological impacts. Winter extremes affect cryptogam physiology, but summer responses appear mild, and lichens affect the photobiont more than the mycobiont. Accounting for Arctic cryptogam response to multiple climatic extremes in ecosystem functioning and modelling will require a better understanding of their winter eco-physiology and repair capabilities.
Sammendrag
Om gjødselprodukt basert på organisk avfall skal erstatte mineralgjødsel må mengde plantetilgjengelig nitrogen være oppgitt. Vi har kartlagt nitrogeneffekten til 25 slike produkt og evaluert hvordan vi best kan bestemme denne i nye ukjente produkt. Resultatene viste at for produkter som har vært gjennom en betydelig nedbrytningsprosess, som for eksempel biorest, er det plantetilgjengelige nitrogenet i all hovedsak lik produktets innhold av ammonium. Resten av nitrogenet er lite tilgjengelig i løpet av vekstsesongen. For faste avfallsprodukt derimot, som i varierende grad er nedbrutt, tørket eller kanskje tilsatt ferskt protein forteller innholdet av ammonium svært lite om nitrogenvirkningen. For slike produkt ligger utfordringen i å skille mellom raskt- og langsomt tilgjengelig nitrogen. Potteforsøk med planter er godt egnet som metode og inkubasjonsforsøk i klima-skap gir resultater som er svært godt korrelert med nitrogeneffekten i potteforsøk. Vi anbefaler at det jobbes videre med å klarlegge sammenhengen mellom nitrogenfrigjøring fra organiske avfallstyper under kontrollerte laboratorieforhold (inkubasjon) og i potteforsøk med et utvalg relevante vekster. Målet må være å etablere en standardisert analysemetode for nitrogenvirkning som kan brukes i produktinformasjon.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Wood modification using polyesterification of sorbitol and citric acid is a novel environmentally friendly strategy for wood protection improving its dimensional stability and acts against fungal deterioration. Inelastic Raman scattering is sensitive to the molecules of high polarizability and both lignocellulose and aliphatic esters formed during the treatment are polar. Therefore, in the present study, the quality control of the treatment using a handheld Raman spectrometer equipped with 830 nm laser is suggested as a rapid and reliable approach. Raman spectra from six wood modification levels (resulting in different weight percent gain, WPG) of three different wood species (Silver birch, Scots pine and Norway spruce) as well as three sample preparation strategies (intact, sanded and milled wood samples) were collected, and further analyzed using a chemometric method. Best performing models based on Powered Partial Least Squares Regression predicted the WPG level at R2 = 0.85, 0.95 and 0.98 for birch, pine and spruce, respectively. In addition, a clear separation between hard and soft wood species was also captured. Especially for softwood species, the sample preparation method affected the model accuracy, revealing the best performance in milled material. It is concluded that by using handheld Raman spectrometer it is possible to perform accurate quality control of wood modified by polyesterification of citric acid and sorbitol.
Sammendrag
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