Mette Thomsen

Research Scientist

(+47) 406 22 631
mette.thomsen@nibio.no

Place
Apelsvoll

Visiting address
Nylinna 226, 2849 Kapp

Abstract

Rhodiola rosea is a perennial flowering plant with a long history as a medicine plant. The plant contain a range of bioactive compounds including salidroside, rosavin, rosarian and rosin. Some of the compounds are characterized as adaptogens, meaning they can increase the body’s resistance to various stressors. An increased demand for better pharmaceuticals has stimulated the development of new methods for agricultural as well as in vitro cultivation of medicinal plants. A new technology, called rhizosecretion of biologically active chemicals, can provide a continuous supply of biologically active compounds over the lifetime of plants. The plants will then be grown under controlled conditions. In order to increase the production of bioactive compounds in Rhodiola rosea under these conditions it is therefore hypothesized that the biosynthesis can be upregulated by growing it under specific temperature and light quality treatments. An experiment with different light and temperature regimes was established for optimal accumulation of biologically active compounds. Four different clones of Rhodiola rosea were grown under three different light conditions (red, blue and white) combined with two different temperatures (9 and 18 °C) for three weeks. The gene expression of Tyrosine decarboxylase (TyrDC), found to have a key role in the biosynthesis of salidroside, were investigated. In addition, the content of various bioactive compounds were quantified before and after treatment. The results indicate that use if high producing clones is most important for high production and that there is a short-term upregulation during blue light treatment. During the three-week treatment, there was no significant effect of the temperature treatments.

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Abstract

Preliminary results on aroma profiles (GC-MS) related to storage conditions (temperature, time and packaging atmosphere) are presented. The vegetables used in the experiments were rutabaga, carrot and turnip, which were peeled and cut before packaging, and stored at two different temperatures. O2 and CO2 concentrations in the packaging atmosphere were measured during the storage period to calculate the respiration rates of the produce. Cubed carrot showed a higher respiration rate than cubed turnip and rutabaga. Samples for analysis of volatiles were taken after 0 and 7 or 10 days. This type of analysis could be used as a complement to sensory analysis.

Abstract

Rhodiola rosea is a well-known herbal medicinal plant, valued for highly active secondary metabolites. It is growing wild in most parts of Norway and mountainous areas in a number of countries. Some of the most important metabolites are believed to be salidroside, cinnamyl alcohol, glycosides (rosine, rosavine, rosarine), flavonoids (rhodionin, rhodiosin,rhodiolin) and terpenes (Galambosi 1999). In Norway, germplasm collections of R. rosea are maintained by NIBIO; at Apelsvoll in southern Norway, consisting of 97 different clones. The ranges in content of secondary metabolites in the collection are for rosavin 2.90-85.95 mg g-1, salidroside 0.03-12.85 mg g-1, rosin 0.08-4.75 mg g-1, tyrosol 0.04-2.15 mg g-1 and cinnamyl alcohol 0.02-1.18 mg g-1. Clones selected from the collection has throughout been studied for different aspects affecting plant growth and production of secondary metabolites. We have looked into cultivation requirements of the plant like water requirement, effects of nutrient levels (N and K) and soil types. Postharvest treatment from washing, cutting,drying and differences in the plant parts. Finally we will in this presentation also present results on requirements for dormancy release and the clonal differences and also how use of primers may affect production of secondary metabolites.

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Abstract

Swede is known as a healthy vegetable with a high content of vitamin C. However, very few studies have worked with the aim to evaluate how varieties, soil type and fertilizer interact and affect quality in swede. In the present study two varieties of swedes (‘Vige’ and ‘Vigod’) were grown on peat, loam and sand, with three levels of K (0, 120, 240 kg ha-1) and N fertilizer (0, 80, 160 kg ha-1). Low to moderate levels of N gave highest saleable yield, highest content of vitamin C and lowest content of nitrate. Peat soil gave highest saleable yield, lowest soluble solids and vitamin C and highest nitrate content. Soluble solids and vitamin C were negatively correlated with total root yield. Sandy soil gave lowest saleable yield, sweetest taste and lowest nitrate content. Contents of total, aliphatic, indole and individual glucosinolates, on dry matter basis, were highest on peat. N fertilization increased the content of most glucosinolates, whereas K affected glucobrassicin at the highest N level. Progoitrin was lowest in roots grown on sand, and was affected by N level and variety on sand and loam soils. Consumers preferred ‘Vigod’, which had the highest intensity of sweetness, although ‘Vige’ had more vitamin C and less nitrate.

Abstract

Optimization of produce quality and storage conditions to reduce loss during long-term storage of root vegetables in Norway (OPTIROOT, 2016-2019) Authors: Thomsen, M.G., Indergaard, E., Asalf, B., Heltoft, P., Wold, A.B., Nordskog, B., Guren, G, Dyste, J. & Larsen, H. Author’s affiliation: Key words: carrot, swede, celeriac, storage technology, diseases, physiological disorder, packaging, nutrition Reducing yield loss along the supply chains is important for resource sustainability in vegetable production. Norwegian root vegetables are typically stored 6 to 8 months before consumption, often resulting in 20-30% loss post harvest. In OptiRoot 26 producers, refrigeration-technology companies, sensor developer, grower’s organisation, agricultural advisory service, and four research institutes are cooperating and conducting research to improve storage quality of carrot, swede and celeriac. The research focuses on: i) Fertilizer/Boron deficiency affects the storage quality of root vegetables and amount, methods of application, and timing of boron are studied in swede and celeriac. ii) Interaction between storage conditions/functions and produce quality of the root vegetables through mapping of technical features of 27 storages. The storage conditions recorded are relative humidity, air movement, temperature in boxes and storages, and physical features of storages. In addition, the physiological and health status of the produces are assessed one week before harvest, postharvest and post-storage. The prevalence of fungal diseases or disorders varied from region to region and between storages. iii) Effects of pre-storage wound healing are tested using seven different temperature strategies (direct to 0° C vs. down 0.2° C per day vs. 1° C per day) and low/high humidity in carrot (2016/17/18), celeriac and swede (2017/18/19). Preliminary results show that wound healing reduced loss due to fungal infections in carrot iv) CO2 concentration, temperature and relative humidity were recorded over time inside carrot storage bin liners with different numbers of perforations. An initial screening indicated a positive correlation between number of holes and number of fresh roots. As a post storage method, coating of swede with chitosan oligomers will be tested to inhibit growth of post-harvest pathogens. In conclusion, OptiRoot have gained good progress and promising preliminary results by connecting data on biology and technology for reduction of loss during long-term storage.

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Abstract

Although grass dominates most agricultural systems in the North Atlantic region (NAR), spring barley is the most important cereal and is used for animal feed and food and drink products. Recent changes in climate have resulted in warmer conditions across the NAR which have major implications for crop production. In this paper, we investigate the thermal requirement of spring barley in the region and use the results to examine the effects of recent trends in temperature and rainfall on barley cultivation, based on 11 regional meteorological sites. At these sites, between 1975 and 2015, we found significant warming trends for several months of the cropping season and significant trends for increases in the cropping season degree days (CSDD). In recent years, this has resulted in an increased proportion of years when the estimated minimum thermal requirement for barley has been met at sites above about 60°N. However, annual variations in CSDD are large and years still occur at these sites where this is insufficient. While warming could potentially allow an earlier start and later end to the cropping season, it is likely that high rainfall at maritime sites, and low rainfall at continental sites, will limit the ability of growers to benefit from this. Warming is considered to have been one of the main factors contributing to the large expansion of the area of barley cultivated in Iceland since the 1990s.

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Abstract

Six clones of Rhodiola rosea, obtained from plants originating from widely different areas in Norway, were investigated for their in vitro inhibitory potential on CYP3A4-mediated metabolism and P-gp efflux transport activity. Presumed active constituents in the ethanol extracts of the different clones were quantified. C-DNA baculovirus expressed CYP3A4 and Caco-2 cells were used for inhibitory assays, and as positive control inhibitors ketoconazole and verapamilwere applied, respectively. A validated HPLC methodology was used to quantify the formation of 6-β-OH-testosterone and scintillation counting was used to quantify the transport of 3H-digoxin in Caco-2 cells. All clones showed potent inhibition of CYP3A4 and P-gp activities, with IC50 values ranging from 1.7 to 3.1 μg/mL and from 16.7 to 51.7 μg/ mL, respectively, being below that reported for other herbs and some known classic drug inhibitors, such as St. John’s wort and fluoxetine. Rhodiola rosea might thus be a candidate for clinically relevant drug interactions. The concentration of presumed biologically active constituents in the different clones varied considerably, but this variationwas not related to the clones’ inhibitory potential on CYP3A4 or P-gp activities. Other constituents might thus be responsible for the observed inhibitory properties. The place of origin seemed to be of minor importance for CYP3A4 or P-gp inhibition.