The side effects associated with commonly used hypoglycemic drugs have spurred the search for effective plant-based remedies for the prevention and treatment of diabetes. This review aims to summarize and systematize available data on the major classes of plant metabolites with antidiabetic properties, the intracellular mechanisms underlying their action, and plant species showing potential antidiabetic activity. We performed a systematic review of 260 studies identified in PubMed, ScienceDirect, and Web of Science, following the PRISMA 2020 guidelines. Numerous classes of plant secondary metabolites, including terpenoids, alkaloids, flavonoids, curcuminoids, stilbenes, phenolic acids, and phenylpropanoids, hold great promise for the prevention of type 2 diabetes. These compounds influence multiple metabolic pathways by inhibiting carbohydrate-metabolizing enzymes, neutralizing reactive oxygen species, reducing blood glucose and pro-inflammatory cytokine levels, increasing intracellular glutathione levels, and protecting pancreatic β-cells from apoptosis. Metabolites with antidiabetic activity can be isolated from plants of various families, such as Asteraceae, Rutaceae, Zingiberaceae, Costaceae, Moraceae, Rosaceae, and Vitaceae. Accordingly, this review proposes candidate plants growing in the Russian Federation (Betula pendula, Quercus spp., Silybum marianum, Hypericum perforatum, Bidens tripartita, Urtica dioica, Taraxacum officinale) as sources of bioactive compounds for the development of drugs to treat type 2 diabetes. The review emphasizes that, despite the potential of plant metabolites to prevent carbohydrate metabolism disorders, several issues remain unresolved, including low solubility and bioavailability, physiological instability, and the lack of standardized plant raw materials and extracts, which is critical for achieving therapeutic effects. Further large-scale in vivo studies are needed to assess the side effects and potential interactions of plant metabolites with conventional drug components. Plant metabolites have demonstrated hypoglycemic and antioxidant effects for the development of antidiabetic drugs, but achieving sustainable results requires addressing key limitations. This review may be useful for research groups and specialists involved in the development and testing of phytochemical platforms, including those with antidiabetic applications.

Traffic-related air pollution is increasingly recognized as a modifier of pollen physicochemical properties and allergenic potential, yet field-based mechanistic evidence remains limited. This study investigated the effects of traffic-related pollution on the morphology, chemical composition, and Bet v 1 allergen content of Betula pendula pollen using a multi-method approach. Pollen samples were collected from 16 B. pendula trees across Ankara, Bingöl, and Tunceli during April 2025 along a traffic-exposure gradient, with air-quality data spanning 1 June 2024-31 May 2025, and sampling sites linked to Türkiye's national air-quality monitoring network (PM₁₀, PM₂.₅, NO₂, NOₓ, SO₂, CO). Pollen was analysed using light microscopy, SEM, FT-IR ATR spectroscopy, and ELISA. Polluted sites (n = 13) showed morphological and biochemical differences compared with clean reference sites (n = 3): pollen exhibited significantly increased exine wall thickness and equatorial dimensions, alongside greater particle deposition near apertures; polar axis showed weaker group-level differences. FT-IR analysis revealed altered protein-related spectral profiles, including an increased Amide I/Amide II area ratio and reduced O-H band areas, consistent with modifications in protein secondary structure. Bet v 1 concentrations did not differ significantly between polluted (95.7 ± 23.8µg/g) and clean (85.5 ± 24.6µg/g) samples; given the small reference group (n = 3), this comparison is interpreted as non-directional. These findings provide field-based evidence that traffic-related pollution is associated with modifications in the structural and biochemical characteristics of B. pendula pollen in ways consistent with enhanced allergenic potential, underscoring the need to incorporate air-quality effects into aeroallergen risk assessment.

ABSTRACT This study examined the structural potential of misfit wood – wood that does not meet the quality or measurement criteria for saw logs due to the curved or bifurcated shape – sourced from continuous forest harvesting. These logs are top segments of felled trees characterized by diverse morphologies with bottom diameters ranging from 96 mm to 187 mm. A total of twenty sizable logs, each measuring between 2,400 and 2,505 mm in length, were tested, including specimens from both Scots pine and silver birch species. Despite variations in shape and thickness, the tests revealed similar behavioural patterns: pronounced nonlinear load-deformation behaviour, and fibre buckling in compression and tensile failure roughly at midspan. The bifurcated specimens experienced fractures at the upper, thicker section of the bifurcation. Comparative calculations with a simplified analytical model, considering curvatures and diameters, demonstrated conservative results. This study has shown that the structural load-bearing capacity of curved and bifurcated round wood can be estimated using the current calculation methods.

A deeper understanding of circadian rhythms in plants, especially trees, is crucial for uncovering how structural and physiological processes align with daily environmental cycles. However, most studies analyze biochemical changes and positional variations separately, with limited exploration of their coordination within the whole-plant system. Hyperspectral light detection and ranging (HSL) integrates three-dimensional (3D) structural mapping with hyperspectral reflectance, enabling non-destructive assessment of plant biochemistry. Previous work showed that HSL can detect nocturnal vertical canopy displacements with centimeter accuracy, but organ-level rhythmic patterns (e.g., branches vs. leaves) remain poorly studied. Here, we developed a hyperspectral point cloud classification method combining spectral and spatial data to separate branches from leaves and analyze their sleep movements independently. A novel sinusoidal-polynomial fitting model was then proposed to characterize circadian rhythms in both sleep movements and reflectance variations. We applied HSL data from a single birch tree (Betula pendula) collected at 30 distinct HSL measurement times over 24h to develop a 3D canopy partitioning approach that divides the canopy into nine grids (3 × 3) and ten vertical layers per grid. Results revealed near-24-hour rhythmic patterns (max R² = 0.5841, P < 0.05) and stratified sleep movements: branches exhibited larger amplitudes than the corresponding canopy layers, with the overall maximum movement amplitude occurring shortly before sunrise (04:00-06:30) and recovering after sunrise. The model also effectively characterized diurnal reflectance variations (max R² = 0.5812, P < 0.05). In addition, chlorophyll-related spectral indices exhibited a sinusoidal variation, reaching a minimum around 03:00. These findings highlight the potential of HSL for the joint analysis of structural and biochemical circadian rhythms, providing a non-destructive approach to investigate plant rhythmicity in both structural and physiological domains.

Climate change and pest outbreaks are increasingly threatening conifer-dominated forests in Northern Europe, highlighting the need for greater species diversity to improve resilience. This study assessed early establishment success of six tree species: European aspen ( Populus tremula ), hybrid aspen ( P. tremula × P. tremuloides ), silver birch ( Betula pendula ), Norway spruce ( Picea abies ), Scots pine ( Pinus sylvestris ), and hybrid poplar ( P. trichocarpa × P. maximowiczii ), across seven sites in southern Sweden. Sites were categorized as either forest land (continuous forest cover >100 years) or forested arable land (former arable land afforested with Norway spruce for 40–70 years). Over three years, we monitored survival, height, and diameter growth. All experimental sites were fenced to exclude browsing. Wood ash was applied to a subset of hybrid poplars to assess its effect on establishment in acidic soils. Our results showed that hybrid aspen, birch, and European aspen had high survival and growth on forest land. On forested arable land, untreated Norway spruce, Scots pine, and hybrid poplar showed low survival, likely due to competition from dense vegetation. However, ash-treated poplar improved survival to approximately 80% and showed strong growth on forested arable sites. Principal Component Analysis indicated overall higher establishment success on forest land for most species, whereas hybrid poplar performed similarly on forest and forested arable land when wood ash was applied. These findings underscore the importance of matching species to site conditions during early establishment and provide empirical evidence to inform species selection for forest regeneration under similar site conditions in southern Sweden. • Site type strongly influenced establishment success of broadleaved trees. • Hybrid aspen and silver birch had the highest survival and early growth on forest land. • Norway spruce and Scots pine performed poorly on forested arable land. • European aspen performed similarly at both site types, demonstrating flexibility. • Results highlight species-site matching for reforestation in southern Sweden.

Wastewater containing safranin from dyes used in textile industries has serious harmful effects on aquatic ecosystems and living organisms. This has led to increased interest in advanced toxicity assessment of this dye and the treatment of its wastewater with sustainable biological removal methods. In this study, using invitro model systems and molecular approach, new insights into the toxicity of safranin were obtained, a sustainable biomass was developed from Betula pendula (BP) biomass, and the detoxification potential of BP biomass was investigated for the first time. Safranin application up to 10 ppm caused significant phytotoxic effects on the physiological parameters of and the anatomical parameters of Allium cepa L. After safranin treatment, significant changes in cytogenetic parameters and oxidant-antioxidant dynamics, including catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and malondialdehyde (MDA), were observed. Molecular interactions between Safranin and target receptors associated with invitro parameters were determined by molecular docking analysis. BP biomass treatment significantly detoxified safranin solutions, and improvements in the values of the tested physiological, cytogenetic, biochemical, and anatomical parameters were observed. Safranin was removed by 98% from aqueous solutions by using BP biomass under optimal conditions. The Freundlich isotherm and pseudo-second-order kinetic models best fitted in isotherm and kinetic studies. Biosorption process occurred spontaneously because ∆G° values were negative in thermodynamic studies. These results suggest that BP biomass is an important biomass for safranin detoxification due to its low cost, sustainable, and effective treatment.

Comparative physical evaluation of adhesive properties in modified gluten

Using native tree species, the phytostabilisation of toxic metals at former mining and industrial sites can provide ways to prevent metal spread and leaching into the environment and bring the sites back into the economic circuit. In this study, mixed afforestations with young trees from seven Central European species showing contrasted autecology (Picea abies (L.) Karst, Fagus sylvatica L., Acer pseudoplatanus L., Alnus incana (L.) Moench, Populus tremula L., Salix viminalis L. and Betula pendula Roth) were exposed during five years to mixed soil contamination (Zn/Cu/Pb/Cd = 1349/317/70/8 mg kg-1). The uptake and allocation of the metals in root and shoot tissues, various functional traits and nutrient responses were compared. Despite high metal availability, all tree species showed low metal uptake and similar metal concentrations in their roots. The mobile metals (Zn, Cd) accumulated in the shoot and foliage of early-successional species with acquisitive ecological strategy only, whereas the late-successional species blocked the transfer of all metals from the roots to the aboveground organs. All species showed good tolerance to metal contamination, with large interspecific differences regarding the biomass production and some nutrient concentrations, in apparent relation to the varying species' ecological strategies and independent of the metal treatment. Zn allocation within fine root tissues could enhance transient spatial and temporal metal immobilisation, especially when associated with protective or defence structures, which also contributed to metal detoxification. Higher transfer of mobile metals to aboveground organs in pioneer tree species was clearly related to their acquisitive ecological strategies, in the context of higher nutrient demand in foliage and lesser defence and protection of vegetative organs. The implications of findings for phytostabilisation applications are discussed.

Abstract In the context of anthropogenic eutrophication of the biosphere, understanding the impact of nutrient addition on plant diversity–productivity relationships remains a major challenge. In particular, the indirect effect of nutrient addition on productivity in tree mixtures via changes in the functional structure of tree communities has never been experimentally quantified and may play an important role in mediating diversity–productivity relationships. Here, we present results from young experimental tree communities 4 years after planting, including monocultures and two‐ and four‐species mixtures of six European species ( Acer platanoides, Betula pendula, Larix decidua, Picea abies, Pinus sylvestris and Quercus robur ) with or without 4 years of mineral fertilizer addition. Using a response‐effect trait framework that links plant functional traits with ecosystem processes, we specifically examined how functional diversity (FD) and community weighted means (CWM) of tree height (H) and specific leaf area (SLA) were influenced by fertilization and to what extent they mediated the fertilization effect on above‐ground productivity in woody tissues. The overall fertilization effect on the degree of community‐level overyielding was marginally positive, yet the influence of fertilization varied significantly depending on species composition. Fertilization affected community functional trait structure primarily by increasing CWM of SLA through dominance of species with high SLA, rather than through intraspecific trait variability. Interestingly, the fertilization‐induced change in CWM of SLA reduced community‐level overyielding. Irrespective of fertilization, CWM of H and SLA influenced community‐level overyielding, while FD had no significant effects. Our results indicate that changes in nutrient availability can influence the magnitude of overyielding indirectly through dominance of species with high SLA in young tree communities. This result improves our understanding of the context dependency of diversity–productivity relationships, which strongly depends on nutrient availability influencing the competitive relationships among tree species. The occurrence of such effects early after tree planting could potentially produce long‐term consequences for tree community composition, and even more so in naturally regenerating forests with less control on tree species selection. Read the free Plain Language Summary for this article on the Journal blog.

ABSTRACT With increasing competition for wood resources, the importance of using small-diameter timber, which consists predominantly of juvenile wood (JW), is growing. The manufacturing of glued products is one way to make rational use of small-diameter wood assortments. However, the properties of JW differ considerably from those of mature wood (MW) and can affect product performance. Radial profile analyses of anatomical structural elements were performed, and based on the fibre length results, the cambial ages of 17 years for silver birch (B. pendula Roth.) and 23 years for Scots pine (P. sylvestris L.) were determined to distinguish between JW and MW. The results showed that the JW of both species had a lower density and higher transverse swelling anisotropy. Lamellae of JW and MW were glued into beams using two one-component polyurethane adhesives and different assembly regimes. The glued beams were then used to prepare samples for delamination tests, performed according to the EN 302-2 standard method for Type I adhesive. Higher resistance to delamination was observed for the JW of both wood species, implying an advantage of laminated products from JW regarding bond-line stability under varying moisture conditions. For pine JW, shorter open assembly times resulted in significantly less delamination.

Post-glacial recolonisation of Fennoscandia created secondary contact zones in many species, offering opportunities to study how gene flow and selection contribute to their establishment and maintenance. Here, we analyse genomic data from three boreal tree species-Picea abies, Betula pendula and Pinus sylvestris-sampled along a latitudinal gradient in Sweden. Despite differences in colonisation timing and dispersal ecology, all three species exhibit north-south genetic structuring aligned with environmental gradients. Most notably, the two main genetic clusters within each species overlap in a shared contact zone, corresponding to the climatic transition between Sweden's two major environmental zones. The extent and structure of the contact zone differ among species: P. abies shows stronger genetic structure and moderate gene flow, B. pendula exhibits intermediate differentiation and gene flow, and P. sylvestris displays the weakest structure with stronger gene flow. All three species also show genomic signatures of local adaptation, with distinct underlying architectures. In P. abies, adaptive loci are broadly distributed across the genome, while, strikingly, they are mostly found within an inversion on chromosome 1 in B. pendula. In P. sylvestris, local adaptation likely relies on subtle allele frequency shifts across many loci with weak signals. These patterns align with theoretical expectations for polygenic local adaptation under varying migration regimes. Our comparative approach demonstrates how gene flow and selection jointly shape genomic landscapes in shared environments and contribute to understanding local adaptation in forest trees, with implications for predicting species' responses to climate change.

ABSTRACT Weevils are notorious pests in conifer regeneration, yet their impact on broadleaved species such as silver birch (Betula pendula) remains poorly understood. This study investigated the incidence and severity of weevil damage on newly planted birch saplings in southern Sweden and tested the effectiveness of Hylonox, a mechanical coating, against weevil attack. A field experiment was established across fresh and one-year-old clear-cuts and damage assessments were conducted over two growing seasons. Strophosoma melanogrammum was the most frequently observed weevil species, followed by Otiorhynchus carinatopunctatus, Hylobius abietis and Hylobius pinastri. Overall, 62% of the birch saplings showed bark damage by weevils, with mortality reaching 16% among the damaged individuals. Mortality was significantly higher in untreated saplings (30%) than in treated ones (21%). Weevil-associated leaf feeding affected 87% of saplings in 2024 and 49% in 2025, but severity was predominantly minor (<20% leaf area affected). Initial sapling height significantly affected both the incidence of bark damage and mortality, with shorter saplings experiencing higher mortality. Ungulate browsing was frequent (45% of saplings), often affecting terminal shoots. The results of this study suggest that weevils can damage birch during early establishment, although mortality is modest relative to that in conifers.

ABSTRACT Herbivory is a source of damage for Fennoscandia commercial stands. Silver birch (Betula pendula Roth) plantations are of increased interest to address the climate and biodiversity crises, but there are concerns about browsing risk. We inventoried 92 planted silver birch stands from a survey focused on browsing variables (e.g. symptom, severity, cause, and position), and one on tree measurements. We estimated ungulate density from national surveys and pellets observation. We assessed landscape characteristics (neighbouring land use/land cover classes and distance to roads). We observed considerable browsing risk for silver birch plantations, with 38 ± 35% and 23 ± 19% of planted birches browsed in younger and older stands, respectively, with mean height <5 and >5 m. Moose were considered responsible for almost half of browsing (44%), while other species accounted for a small amount (4.1%), the majority by unidentified cervids. Especially, crown damage in younger stands developed into vertical branches in older stands, leading to low stem external quality. In a model predicting the number of browsed stems at stand level, damage occurrences were dependent only on stand characteristics and abundance of browsing animals. Our analysis could not provide site selection recommendations for lower browsing risk sites. However, avoiding early damage seems the most crucial step.

Morphological characteristics of pollen grains, including shape, size, pore number, and exine thickness, vary significantly among species and enable the reliable use of palynological data in taxonomic studies. In this context, the present study investigates the pollen morphology of seven Betulaceae taxa (Alnus glutinosa, Betula pendula, Carpinus betulus, Carpinus orientalis, Corylus avellana, Corylus colurna, and Ostrya carpinifolia). Detailed morphometric measurements were carried out using Light Microscopy (LM), and high-resolution images were obtained using Scanning Electron Microscopy (SEM). For each taxon, thirty measurements were taken for the main pollen characters, including polar axis length (P), equatorial diameter (E), pore length (plg), pore width (plt), and exine thickness (Ex). Interspecific differences were evaluated using one-way ANOVA, Tukey's HSD test, and Principal Component Analysis (PCA), and a diagnostic pollen identification key was developed for the investigated species. The results demonstrate statistically significant interspecific variation in pollen size, pore characteristics, and exine thickness. In the PCA ordination, the first principal component (PC1) was mainly associated with pollen size (P and E), clearly separating Carpinus betulus from the remaining taxa. The second principal component (PC2) was primarily related to pore length (plg) and contributed to the separation of Alnus glutinosa from the other small-pollen species. These results show that quantitative pollen morphological characters provide reliable criteria for distinguishing closely related Betulaceae taxa.

The transition from pure to mixed-species forest stands is increasingly promoted to enhance ecosystem stability and multifunctionality. The growth conditions may influence the physical and mechanical properties of wood. This study evaluated wood density in pure and mixed stands of silver birch, Norway spruce, and Scots pine in Lithuania and analyzed its relationships with tree allometric parameters. Nine study plots representing pure (100%) and mixed (70/30%) stands were established under comparable site conditions. Wood density at breast height was assessed using resistance drilling (IML Resi PD500), and the increment core samples were analyzed with the LIGNOSTATION™ system. The mean values of wood density for silver birch differed by 11%, depending on the wood density determination method used. Differences between pure and mixed stands were insignificant and generally did not exceed 6%–10%. No consistent trend that was attributable to species mixing was identified. The combined data from pure and mixed stands indicate that the mean wood density, converted from microdrilling measurements, was highest in silver birch (546 kg m−3 ± 1.87 kg m−3), followed by Scots pine (476 kg m−3 ± 1.85 kg m−3) and Norway spruce (437 kg m−3 ± 1.66 kg m−3). Resistance drilling showed a moderate relationship with the core samples’ wood density (R2 = 0.59), supporting its suitability as a semi-nondestructive method. Diameter at breast height was the only tree parameter that was consistently significant across all predictive models. The combined model for all species explained up to 43% of wood density variation, while species-specific models had lower explanatory power. Overall, the results indicate that species mixing has a limited effect on wood density under the studied conditions and is unlikely to substantially alter wood quality in terms of wood density.

Birch tar is well-documented for its use as an adhesive in the Middle Palaeolithic of Europe, but other uses remain poorly explored. Drawing from recent arguments suggesting multimodal uses of products such as ochre and birch tar, this study tests the antibiotic properties of birch tar produced experimentally with methods reconstructed from Middle Palaeolithic birch tar finds from Europe. Made from the bark of Betula pendula and Betula pubescens, widely documented for the European Late Pleistocene, we produced birch tar samples using an underground pit method, a condensation method, and a modern tin can method. The birch tar samples were tested for antibiotic properties using the modified Kirby-Bauer disc diffusion antibiotic assay. The resulting inhibition zones, ranging from no effect to 10.5 ± 0.7 mm with a mean of 7.5 ± 0.17 mm, indicate a moderate effect against the Gram-positive Staphylococcus aureus, a bacterium widely known for its role in wound infections. We further establish that the efficacy of antibiotic properties is not related to the production method, with all methods showing a degree of variation. This supports a coevolutionary relationship between medicinal and technological use and production of birch tar during the Pleistocene. The antibiotic properties documented in this study are consistent with the use of birch tar as a wound dressing and skin ointment in Mi’kmaq communities in Eastern Canada, and the use of birch tar in Saami communities of Lapland. Arguing from an underexplored angle between experimental archaeology and ethnopharmacology, we suggest that similar to the ethnographic examples, a use of birch tar beyond exclusively technological contexts must be considered for the Middle Palaeolithic.

ABSTRACT Mixed forests are expected to be highly productive carbon (C) sequestering ecosystems. The study reports the effect of stand age on net ecosystem production (NEP) in a hemiboreal mixed forest chronosequence composed of silver birch and Norway spruce. The biometric C budgeting method was applied in seven chronosequence mixed stands aged between 20 and 70 years. Average NEP across the studied development classes ranged from 3.8 to 5.3 tC ha−1 yr−1. The highest value of NEP, 7 tC ha−1 yr−1, was estimated for a 30-year-old middle-aged stand. The main driver shaping the annual NEP of the stands along the successional gradient was the net primary production (NPP) of trees, while the contribution of the ground vegetation was minor. Annual cumulative soil heterotrophic respiration (Rh) varied between 4.1 and 5.5 tC ha−1, irrespective of stand age. Birches produced the major share (61%) of the annual aboveground litter input to the soil while the belowground C input through fine root production was largely formed of spruces (63%). The studied birch-spruce mixed stands on fertile soils acted as strong C sinks. Still compared to the literature data for corresponding pure stands, no overyielding effect of mixed stands was revealed.

Sustainable glycerol-based extraction of bioactive compounds from tree bark for transdermal applications

The article presents the results of a study of constructed composites based on degradable poly(3-hydroxybutyrate) (P(3HB)) filled with plant materials of 30, 50, and 70% of different origin-wood flour (WF) from birch (Betula pendula), hemp hurds (HH) or hemp fiber (HF) (Cannabis sativa). Composite bar samples were obtained by hot pressing homogeneous mixtures of polymer and fillers at 170 °C and a specific pressure of 6.13 MPa. The influence of the filler type and the polymer/filler ratio on the temperature characteristics of the samples, density, microstructure, surface properties, water absorption, physical and mechanical properties, and degradability in soil was determined. The Young's modulus of the samples ranged from 2640 to 3715 MPa, depending on the composition. The maximum degradation of the composites after 120 days of exposure to soil was recorded at 70% WF, HH, or HF filling, amounting to 77.4, 63.5, and 38.6%, respectively. Perspective biodegradable composites based on P(3HB) filled with various plant-based fillers were obtained and characterized, along with new knowledge about their properties, the lack of which currently hinders the active development and commercialization of such in-demand materials.

IntroductionPolymerized allergen extracts are widely used in allergen immunotherapy (AIT) to reduce allergenicity and enhance safety. However, the impact of cross-linking stoichiometry on the structural and allergenic properties of these polymers remains insufficiently characterized. This study systematically investigates how varying glutaraldehyde-to-protein ratios influence the resulting polymers and their potential relevance for AIT.MethodsPollen extracts from Phleum pratense and Betula verrucosa were polymerized using five different glutaraldehyde-to-protein ratios. The resulting polymers were structurally characterized using SDS-PAGE, nuclear magnetic resonance (NMR), transmission electron microscopy (TEM), and mass spectrometry (MS). Allergenicity was evaluated by measuring the immunoglobulin E (IgE) reactivity through enzyme-linked immunosorbent assay (ELISA), Western blotting, and mast cell activation test (MAT). Immunogenicity was assessed by analyzing the serum-specific IgG and ex vivo lymphocyte responses in mice immunized with the least allergenic polymer formulation.ResultsAll cross-linking conditions produced polymers with distinct differences in size, morphology, and yield. Despite retaining similar peptide profiles to native allergens, as confirmed by MS, the polymers exhibited increased stability, as shown by NMR, and significantly reduced allergenicity, according to ELISA and MAT. Notably, increased polymer size and density, as determined by NMR and TEM, correlated with lower allergenicity. The most extensively cross-linked high-density polymers, optimized for minimal allergenicity, elicited immunogenic responses comparable to those induced by native extracts when tested against unmodified allergens.ConclusionCross-linking stoichiometry critically shapes the structural and immunological properties of polymerized allergen extracts. Adjusting the glutaraldehyde-to-protein ratio to produce highly polymerized, dense polymers enables a well-balanced profile of safety and efficacy for use in AIT.