Empetrum Nigrum Research Articles

Analysis of Empetrum nigrum L. lipophilic secondary metabolites, their metabolomic profiles and antioxidant activity

ABSTRACT Fourteen hexane-soluble polyphenolic secondary metabolites were previously isolated as individual compounds from Empetrum nigrum L. and identified as three bibenzyls, four 9,10-dihydrophenanthrenes, two chalcones, four dihydrochalcones and one flavanone. In this study, the mass-spectra and retention indexes (RI) of compounds 1-14 without prior derivatization were obtained and the resulting fragmentation pathways rationalized in accordance with literary data and the compounds structures. Preliminary differences in metabolite composition were assessed by comparative profiling using GC-MS chromatography combined with multivariate data analysis for a limited amount of E. nigrum n-hexane extracts obtained from plants growing in three different geographic locations. To characterize antioxidant capacity of isolated compounds 1-14 we used our well-established model based on reactive oxygen species (ROS) production by activated human platelets and showed that most of the examined polyphenols act as antioxidants by inhibition of ROS production.

Редкие сообщества асс. Molinio caeruleae–Trollietum europaei ass. nov. в Хибинских горах (Кольский полуостров)

Mountain tundra meadows with dominance of Molinia caerulea were found in the Khibiny Mountains (Kola Peninsula) (Fig. 1) and described based on the Braun-Blanquet approach. Ass. Molinio caeruleae–Trollietum europaei ass. nov. (Fig. 2, Table, holotypus — relevé 7, 67.611327° N, 33.61316° E; 530 m a. s. l.) is ascribed to the alliance Potentillo–Polygonion vivipari Nordh. 1937, order Epilobio lactiflori–Geranietalia sylvatici Michl, Dengler et Huck 2010, and class Mulgedio-Aconitetea Hadač et Klika in Klika et Hadač 1944. The diagnostic species are Achillea apiculata, Dianthus superbus, Festuca ovina, Geranium sylvaticum, Melica nutans, Molinia caerulea, Trollius europaeus, Vaccinium myrtillus. The undergrowth layer is sparse and composed with Betula nana, Cotoneaster cinnabarinus, Juniperus sibirica. In the upper layer (about 0.5–0.8 m high) most abundant are tall herbs (Molinia caerulea, Dianthus superbus, Geranium sylvaticum, Trollius europaeus and Cirsium heterophyllum). Lower layer (0.1–0.3 m high) is composed with low herbs (Anthoxanthum alpinum, Bistorta vivipara, Epilobium lactiflorum, E. hornemannii, Festuca ovina, Veronica alpina, Viola biflora, V. canina subsp. montana) and dwarf shrubs (Empetrum hermaphroditum, V. uliginosum, V. myrtillus). Ground layer is prostrate and consists of Sciuro-hypnum starkei, S. reflexum, Sanionia uncinata, Bryum spp. and Polytrichum spp. Association comunities occupy rather large areas and are located above the tree line and in the lower part of the mountain-tundra belt, at 410–540 m a. s. l., on well-moistened steep (45–50°) rocky slopes, exposed to southwest and southeast, near groundwater outlets or in places of late snowmelt. Probably the association is of relic nature and marks the tree line of the warmest Holocene period. Rich of species, including Red Data Book Cotoneaster cinnabarinus, Epilobium lactiflorum, Veronica fruticans, it is a value habitat type «E2.3 Mountain hay meadow» in the Kola Peninsula.

The content of nutrients, lignin and cellulose in plants and lichens in the forest-tundra ecotone of the Khibiny mountain massif

The results of studies of the chemical composition of plants and lichens in the altitude gradient on the slope of Yumechorr of the Khibiny mountain massif (Murmansk region) are presented. The species specificity of the accumulation of macro- and microelements by the assimilating organs of plants and lichens in the in the main altitude zones is shown. The leaves of Betula pubescens and Vaccinium myrtillus are the most rich of elements of mineral nutrition. Lichens are characterized by a low content of N, Ca, K, P, Mg, S, as well as Zn and Mn and high - Fe, Cu, Ni. In spruce and pine needles, similar patterns of the distribution of elements by age classes were revealed. Changes in the content of nitrogen, mineral elements, secondary metabolites in the altitude gradient in the assimilating organs of plants and lichens, during the transition from the forest belt to the mountain forest, have been established. It has been established that with increasing growth height, the N content increases in Pinus sylvestris needles, in the leaves of Arctostaphyllos uva-ursi, in the leaves of the current year Empetrum hermaphroditum. Plants growing in the mountain tundra and forest tundra are characterized by a high content of K. The Zn content also increases with increasing absolute height in the conifers/leaves of P. sylvestris, B. pubescens, V. uliginosum. During the transition from the forest belt to the mountain tundra, the content of Ca and Mg decreases in plant leaves. In the leaves of E. hermaphroditum, minimal concentrations of Mn were also detected in the mountain tundra. The content of lignin and cellulose in the leaves of shrubs, with the exception of V. myrtillus, in the belt of coniferous forests is lower than in the belt of birch forests and tundra. The content of lignin in the leaves of B. nana and B. pubescens increases, and cellulose practically does not change with an increase in absolute height in the Khibiny Mountains. Accumulation of lignin is observed in needles of P.sylvestris in the belt of birch woodlands.

Растительность торфяных бугров болотных комплексов севера Западной Сибири и полуострова Таймыр

Растительность торфяных бугров болотных комплексов севера Западной Сибири и полуострова Таймыр

Autumn food of rock ptarmigan Lagopus muta: the effect of age, sex, year and location

We analysed food data for rock ptarmigan Lagopus muta collected during a 10 day period at the end of September and beginning of October 2006–2014 in northeast Iceland or for nine years. The total sample was 679 birds, including 455 juveniles and 224 adults; the annual range was 48–88 birds. To describe the importance of items consumed we used percentage by dry biomass (total 1399 g) and percentage by frequency of occurrence. A total of 80+ species were identified, the most important were Betula nana (27% biomass, 62% frequency), Empetrum nigrum (14%, 63%), Dryas octopetala (11%, 64%), and Salix herbacea (10%, 41%). Important plant parts consumed were berries, woody shoots with buds, buds, catkins, seeds and leaves. Difference in diet, both with respect to species and plant parts consumed, depended on year and altitude of collection site but not on ptarmigan sex, age or sex*age interaction. The only significant age difference observed was that juveniles consumed more seeds and less woody parts than did adult birds. Betula spp. dominated the diet in five years and Salix spp. in four years. Betula and Vaccinium spp. were most important at low and medium elevations but Salix spp. showed an opposite pattern. Berries (E. nigrum and Vaccinium spp.) were the dominant plant parts in the diet for six years and woody parts of Salix and Betula spp. in three years. Berries dominated in the diet at low to medium elevations and woody parts showed an opposite pattern.

Relations of Phenolic Compounds, Tannins, Lignin, Nitrogen and Carbon in Plants of the Empetro-Piceetum Forests of the Kola Peninsula

The study presents an analysis of aging (falling) organs (leaves/needles) of the following plants: Siberian spruce (Picea abies ssp. obovata (Ledeb.) Domin), downy birch (Betula pubescens Ehrh), common cowberry (Vaccinium vitis-idaea L.), crowberry hermaphroditic (Empetrum hermaphroditum Hager.), blueberry (Vaccinium myrtillus L.), Schreber’s pleurium (Pleurozium schreberi (Brid.) Mitt.), polytrichum (Polytrichum spp.), dwarf cornel (Chamaepericlymenum suecicum (L.) Aschers. Graebn. (Cornus suecica L.)), wavy hair-grass (Deschampsia flexuosa (L.) Trin.). A significant variation in the chemical composition (the content of lignin, phenolic compounds, tannins, nitrogen and carbon, as well as the stoichiometric ratios “C/N”, “lignin/N”, “lignin/cellulose”) was found among plants of the northern taiga forests at the interspecific level. The influx of secondary metabolites with litter depends on the plant communities’ species composition and the contribution of various plant species to the vegetation cover’s composition. At the intraspecific level (for Siberian spruce growing in different landscape positions within empetro-piceetum forests (in automorphic, transit and accumulative landscapes)) an increase in the content of soluble tannins (p 0.05) in spruce needles from the automorphic positions of landscape was determined. Also have been studied some interrelations between secondary metabolites, nitrogen and carbon in the composition of aging photosynthetic organs of dominant plant species in northern taiga empetro-piceetum forests.

Фенольные соединения и лигнин в растениях еловых и сосновых лесов в условиях промышленного воздушного загрязнения

The changes in the content of phenolic compounds and lignin in the needles/leaves of six plant species growing in spruce and pine forests of the Kola Peninsula, including those exposed to industrial air pollution (Cu, Ni) of varying degrees of intensity, were established. The results obtained indicate that the reaction to industrial pollution largely depends on the type of plant and the place of growth. Some plant species adapt to increased anthropogenic loads by increasing concentrations of phenolic compoundsand lignin, while others, on the contrary, reduce these indicators. Such, changes in perennial needles/leaves of plants can lead to a change in the rate of decomposition of this litter, which can affect the functioning of the ecosystem (for example: slowing down the biogeochemical cycles of nutrients). Biochemical monitoring of Empetrum hermaphroditum looks very promising, because of its resistance to contamination and an unambiguous reaction to it in both spruce and pine forests.

Extraction and Preconcentration of the Main Target Polyphenols from Empetrum nigrum by Freeze-Ultrasonic Thawing Method Based on Synthetic Gemini Surfactant Aqueous Systems

Extraction and Preconcentration of the Main Target Polyphenols from Empetrum nigrum by Freeze-Ultrasonic Thawing Method Based on Synthetic Gemini Surfactant Aqueous Systems

Alpine and Arctic tundra shrub populations show similar ontogenetic growth trends but differing absolute growth rates and lifespan

The majority of terrestrial primary production is performed by plants, the ontogenetic growth trends of which significantly influence biomass and carbon dynamics. Here, we present a study of ontogenetic trends in primary (apical) and secondary (stem thickening) growth of plants in Arctic (Svalbard, Norway) and alpine (Krkonoše, Czechia) populations of the black crowberry (Empetrum nigrum), the dominant plant species of certain tundra communities. The environmental conditions in alpine areas are more favourable for plant growth than those in the High Arctic, where temperatures are lower, there is less precipitation and soils are shallower, among other differences. These differences were clearly reflected in significant distinctions in absolute growth rates and shrub age between the populations under study. However, we found almost no divergence in ontogenetic growth trends between the populations (based on ring width measurements made from the base to the top of plants, known as serial sectioning). In both populations, primary and secondary stem base growth decrease over the course of ontogeny whereas secondary stem top growth and basal area increment increase. No significant differences in the slope of the trends were found in either primary or secondary stem base growth. Trends of the growth ratio between basal area increment and primary growth revealed neither absolute nor relative differences between the populations. Ontogenetic trends in the shrubs analysed were surprisingly stable despite the prominently dissimilar environmental conditions. Empetrum plants have adapted to the different environments by altering their absolute growth rate only. This adaptation has probably also resulted in the different longevity of plants constituting the study populations, confirming the theory that slower-growing plants live longer. Primary growth and secondary stem base growth seem to be more basic characteristics of plant growth compared to basal area increment and secondary growth at the apex because the latter two seem to be dependent on the absolute growth rate.

Twenty-one year dynamics of vegetation from long-term plots in East European tundra

Twenty-one year dynamics of vegetation from long-term plots in East European tundra

Betula alba Bark Extract and Empetrum nigrum Fruit Juice, a Natural Alternative to Niacinamide for Skin Barrier Benefits.

The Scandinavian region is home to a unique biome with endemic plant species. The aim of this study was to explore this natural diversity and identify plant extracts providing positive skin barrier effects. Six plant extracts were identified as starting material. Following biochemical screening, two candidates outperformed the rest: Betula alba (BA) and Empetrum nigrum (EN). Quantitative PCR analysis showed that BA and EN upregulated barrier genes, when used individually and in combination. Betula alba increased AQP3 and OCLN protein expression, something niacinamide was incapable of. Additionally, the skin barrier was strengthened, evidenced by inhibition of KLK5 and hyaluronidase and showed strong antioxidant and anti-inflammatory activity through DPPH and COX2 inhibition, respectively. A first split-face clinical study was conducted using the combination of extracts versus placebo. There was a significantly better skin restructuring effect and corneocyte cohesion on the side treated with combined extracts. A second split-face clinical study assessed the combined extracts versus 3% niacinamide. Significant variations in skin hydration and TEWL were observed in favor of the extract treated side. In conclusion, we identified a natural alternative to niacinamide for improving skin barrier health, in Scandinavian plant extracts, which yield strong performance, but at a lower concentration.

Response of ground macrolichens to site factors, co‐existing plants and forestry in boreal forests

AbstractAimGround lichens have declined in boreal and temperate Europe. The potential causes of the decline were explored by analysing the response of lichen cover to forest management, site and stand variables as well as co‐existing plants in different boreal vegetation subzones.LocationFinland.MethodsUnderstorey vegetation was surveyed on a systematic network of 1721 sample plots in forests on mineral soil. The response of macrolichen cover to explanatory variables was analysed by generalised linear mixed models (GLMMs).ResultsGround lichens favoured old Pinus sylvestris forests on xeric sites with sufficient light conditions. Intensive forest management regimes, such as regeneration cutting and soil ploughing decreased lichen cover, while lighter scarification methods had less effect on lichens. Lichens benefitted from intermediate cutting on sites with low bryophyte cover. Lichens responded similarly to site and stand variables in all boreal subzones, showing that despite heavy reindeer grazing these response patterns apply also in the northern boreal subzone. Lichens showed both negative (Vaccinium myrtillus, Empetrum nigrum and Calluna vulgaris) and positive (Vaccinium vitis‐idaea) responses to increasing dwarf shrub cover. Generally, lichens negatively responded to increasing bryophyte cover, indicating either that bryophytes benefit from a decline of lichens or that there is real competition between these groups. The negative relationship between bryophytes and lichens strengthened as the tree canopy becomes denser.ConclusionsOur study provides new quantitative insights into the effects of forest management and changes in forest structure as underlying factors for lichen decline both inside and outside the reindeer‐herding area (i.e., the northern boreal subzone). These factors include increased canopy cover with increased shading as well as disturbance caused by regeneration cutting and soil preparation. The possible effects of the long‐term legacy of nitrogen deposition, lack of forest fires and climate change are also discussed.

Practical Application of Empetrum Nigrum Extract in Brewing

The article presents the developed formulation of a new variety of light beer with the dry extract of the Empetrum nigrum added. For this purpose, the authors obtained Empetrum nigrum dry extract, which contains 3.40% phenolic substances, including 0.56 % simple phenols; 1.16 % flavonoids, represented by coumarins, chalcones and aurones; and 79.8 % carbohydrates. A man added dry extract Empetrum nigrum to the hopped wort before fermentation in an amount of 0.5 g/l. At this concentration of the added extract, there is an alcoholic fermentation activation, which is evident as an increase in acidity, color and the number of yeast cells in the wort during fermentation to 7.725·107 CFU/ml. The researchers revealed that the beer, obtained according to the developed recipe, had improved organoleptic properties; the taste and aroma of a drink are notable for the pleasant sweetness and herbaceous shade.

Determination of the anthocyanine profile and optimal parameters of their extraction from <I>Empetrum nigrum</I> fruits

Aim. To determine the profile of anthocyanins and optimal parameters of their extraction from Empetrum nigrum fruits.Materials and methods. Anthocyanins contained in the dried fruits of Empetrum nigrum were identified using HPLC and mass spectrometry. The anthocyanin content was determined using differential spectrophotometry.Results. Empetrum nigrum fruits were found to contain the following substances: delphinidin, cyanidin, petuinidin, peonidin, and malvidin. The main anthocyanins comprised cyanidin-3-galactose (33.068%), delphinidin-3-galactose (21.733%), and malvidin-3-galactose (15.374%). The necessary conditions for the maximum extraction of anthocyanins from Empetrum nigrum fruits were established to be as follows: the use of 70% ethyl alcohol containing hydrochloric acid as an extrant; a sample weight of 1.0 g; a particle size of 1.0 mm; the 1:70 ratio of raw materials and extractant; an extraction time of 90 min.Conclusions. The Empetrum nigrum fruits grown in the Kamchatka region were found to contain eight anthocyanins were identified. The anthocyanin content comprised 5.65 ± 0.04%.

Total synthesis and antibacterial evaluation of Empetroxepins A and B and related analogs

Empetroxepins A and B, which are 10,11-dihydrodibenz[b,f]oxepins produced by the Black Crowberry (Empetrum nigrum), displayed weak anti-tubercular activity upon isolation, but have not been explored for antibiotic activity despite their molecular similarity to other phenolic antibacterial natural products. Herein we detail the first total synthesis of Empetroxepins A and B via a selective demethylation strategy and antibacterial structure activity relationship (SAR) study of the natural products and related analogs. Empetroxepin A was found to be weakly active against susceptible strains of Staphylococcus aureus (SA) and Bacillus subtilis (BS) with a minimum inhibitory concentration (MIC) of 256 μg/mL against both bacteria, whereas Empetroxepin B was found to be weakly active against only BS (MIC = 256 μg/mL). Neither natural product was active against Escherichia coli (EC). Antibiotic activity was improved through derivatization of the 10,11-dihydrodibenz[b,f]oxepin core with the best compound of the SAR series, 9-chloro-10,11-dihydrodibenzo[b,f]oxepine-2,3,4-triol, having MICs of 8 μg/mL, 16 μg/mL, and 256 μg/mL against SA, BS, and EC respectively.

The study of composition, acute and chronic toxicity of liquid extract of herbs of empetrum nigrum

The study of composition, acute and chronic toxicity of liquid extract of herbs of empetrum nigrum

Substantiation and Development of Bakery Products Enriched with Arctic Vegetable Raw Materials

A man implements the development programs of the Arctic territory including the Yamalo-Nenets Autonomous District (Yamalo-Nenets Autonomous Okrug) actively. One of the development program goals of the Yamalo-Nenets Autonomous District is to ensure the food security of the region and the healthy lifestyle formation of the population aimed at preventing diseases. According to Rospotrebnadzor, in recent years infectious diseases have become widespread in the region due to the population immunodeficiency. A man decided to develop a complex dietary supplement with immunomodulatory properties and the feasibility to introduce it into the product of mass production. A group of bakery products was the basis of the functional product. The article presents the study results of bakery products enriched with plant raw materials – cinnamon rose (Fructus Rosae) and shiksha (black crowberry, Empetrii nigri herba) growing in the Yamalo-Nenets Autonomous District. The research aim is to substantiate the development of bakery products of mass demand enriched with a complex food additive based on Arctic plant raw materials. The preparation technology includes the main stages: sorting raw materials; grinding dry concentrates; heating it in a bioreactor and packaging. The researchers used raw materials in dry form: cinnamon rose hips – TU 10.89.19-036-14721358-2017; shiksha (black crowberry) – TU 10.89.19-086-14721358-2017). The organoleptic and physico-chemical analysis of the resulting product showed its compliance with the current regulations for food products. A positive assessment in terms of safety and compliance with functional properties enables to qualify an additive from plant raw materials as functional food ingredients – GOST R 54059-2010 “Functional Food Products. Functional Food Ingredients. Classification and General Requirements: National Standard of the Russian Federation”. The bakery product itself refers to products enriched with functional food ingredients – GOST R 55577-2013 “Specialized and Functional Food Products. Information on Distinctive Features and Effectiveness: National Standard of the Russian Federation”.

Antimicrobial Activity of Polyphenolic Compounds

Introduction. The emergence of new strains of microorganisms with multidrug resistance (MDR) is one of the most pressing problems of modern medicine. Currently, to combat MDR, active attempts are being made to obtain new biologically active substances of natural (microbial, plant, animal) origin. Earlier, 32 individual compounds were isolated by the authors from the aerial part of Iris laclea Pall., Rubus chameamorus L. leaves, Empetrum nigrum L. shoots, Ononis arvensis L. aerial part and Solidago canadensis L. aerial part, and 2 more compounds were synthesized according to previously published methods. The study of the antimicrobial activity of compounds of these classes is an urgent problem for finding potential agents for combating MDR. Aim. Studying of the antimicrobial activity of the isolated and synthesized substances in an individual form against Staphylococcus aureus , Escherichia coli and Candida albicans . Materials and methods. To test the antimicrobial activity, substances of 34 compounds were used, which were obtained as a result of previous research, the structure of which were established using NMR spectroscopy and high-resolution mass spectrometry. The antifungal and antibacterial activity of the compounds were determined through the micromethod of two-fold serial dilutions in liquid nutrient medium in 96-well plates in duplicate. Screening for antimicrobial activity was carried out against reference (type) strains of Staphylococcus aureus ATCC 6538-P, Escherichia coli ATCC 25922, Candida albicans NCTC 885-653. Results and discussion. In the group of flavonoids and O-, C-glycosides, the antifungal activity of all studied compounds did not differ significantly, but it should be noted that the antibacterial activity of apigenin C-glycosides and isoflavonoid O-glycosides was slightly greater in comparison to O-glycosides of flavonols. The greatest antimicrobial activity among the group of chalcones was shown directly by the chalcones themselves – chalcone, 2’, 4’-dihydroxychalcone, and 2’-hydroxy-4’-methoxychalcone. Among the dihydrochalcones, the highest antimicrobial activity was found for 2‘, 4’-dihydroxyhydrochalcone, which was comparable in magnitude to the antimicrobial activity of the chalcones themselves. An interesting feature of dihydrochalcones is that methylation of phenolic hydroxyl groups in the 2‘ and 4’ positions decreases the antimicrobial activity. The antimicrobial activity of 9,10-dihydrophenanthrenes, as in the case of dihydrochalcones, depended on the number of methoxy groups in the molecule. The lowest MIC values were exhibited by 4,7-dihydroxy-2,3-dimethoxy-9,10-dihydrophenanthrene containing only two methoxy groups. For bibenzyls, an inverse dependence of antimicrobial activity on the number of methoxy groups was observed – the best activity among bibenzyls against the studied strains was shown by 1-(3-hydroxyphenyl)-2-(3-hydroxy-4,5-dimethoxyphenyl)ethane, which contains two methoxy groups in its structure. Conclusion. Polyphenolic secondary metabolites of plant origin belonging to the studied groups: flavonoids and O-, C-glycosides, chalcones, 9,10-dihydrophenanthrenes and bibenzyls did not show significant antimicrobial activity against the studied strains of microorganisms – S. aureus (6538 EP ATCC), E. coli (25922 ATCC) and C. albicans (885-653 NCTC). Despite this fact, a certain variation in antimicrobial activity was revealed depending on the structure of the tested substances.

Alpine ericaceous dwarf shrubs as summer food resources for Asiatic black bears in Japan

The Asiatic black bear (Ursus thibetanus) is known to use the fruits of various fleshy-fruited plant species as food resources. However, there is no published evidence regarding whether they feed on the berries of 4 ericaceous dwarf shrub species that are widely distributed in alpine regions in Japan (Empetrum nigrum, Vaccinium uliginosum, Gaultheria pyroloides, and Vaccinium vitis-idaea). We assessed the use of, and preference for, these berries by black bears and identified the production and morphological and nutritional characteristics of these berries in the alpine zone of Mt. Asama, central Japan. Using camera-trap survey and scat analyses between July and November in 2017, 2018, and 2019, we obtained the first evidence that these bears consume large quantities of E. nigrum berries in the alpine zones during the summer. The density of berries per square meter was highest for E. nigrum. By contrast, the cost–benefit ratio of morphological fruit attractiveness (i.e., fresh pulp weight and dry pulp weight divided by total fresh seed weight per fruit), crude protein, crude fat, and nitrogen-free extract levels were lowest in E. nigrum berries. Therefore, fruit use by black bears appeared to be influenced by fruit production rather than the morphological or nutritional value of the fruits. Bears may compensate for this nutritional deficit by consuming large quantities of these berries. Consequently, E. nigrum berries are key food items for black bears in Japan and may compensate for summer food shortages.

The application of dendrometers to alpine dwarf shrubs – a case study to investigate stem growth responses to environmental conditions

Abstract. Considering the recent widespread greening and browning trends associated with shrubs in arctic–alpine ecosystems, further understanding of how these shrubs respond in a rapidly changing environment is of crucial importance. We here monitor shrub growth, using high-precision dendrometers to produce fine-scale intra-annual growth patterns from hourly stem diameter variability in a widespread evergreen species (Empetrum nigrum ssp. hermaphroditum). Measurements were taken at a micrometer scale for the period 2015 till 2018 on exposed and mostly snow-free ridge positions. With the same temporal resolution, we collected near-ground environmental data and identified on-site controls of growth behavior. We found high inter-plant variability in radial stem growth but strong similarities in response patterns to the local environment. Our results suggest that the evergreen species is highly adapted to the specific local conditions, remaining partly photosynthetically active during the snow-free winter, which facilitates carbohydrate accumulation for early-season physiological activities. Additionally, we discovered a phase of radial stem shrinkage during the winter months, which can be attributed to an active cell water reduction to protect the plant from frost damage. We conclude that soil moisture availability and winter snow conditions are the main drivers of radial stem growth of E. hermaphroditum in arctic and alpine regions and could negatively affect the species' distribution in a warming climate.