Allergenic Tree Species Research Articles

Comprehensive study of allergenic tree species: Palynological insights enhanced by HPLC and GC-MS profiling.

Considering the limited data available on tree species in Uzbekistan, this research aimed to provide new insights. We gathered plant samples from different locations within Samarkand city and thoughtfully selected 15 tree species that represent the country's flora. Using scanning electron microscopy, we conducted comprehensive analyses of pollen morphology, revealing a diverse range of variations in the shapes, dimensions, and surface characteristics displayed by pollen grains. Distinct ornamentations such as micro-echinate, reticulate, rugulate, gemmate-verrucate, and verrucate-scabrate patterns facilitated the differentiation of species. These scanning electron microscopy findings enhance our comprehension of tree species diversity, adaptation, and ecological roles. In addition, leaf extracts were analyzed using HPLC and GC-MS, revealing a plethora of bioactive compounds, including catechins, chlorogenic acid, vanillic acid, and others. Furthermore, GC-MS analysis revealed the presence of seven key compounds, including 1-hexadecyne, 2-chloroethanol, 1,6-heptadiene, 2-methyl-, 5-bromoadamantan-2-one, ethyl 3-(3-pyridyl) propenoate, bis (2-ethylhexyl) phthalate, and quercetin. This study demonstrates the effectiveness of this method in assessing the quality of leaf extracts from tree species by examining both microscopic characteristics and chemical composition. This multifaceted approach has deepened our understanding of the characteristics and chemical compositions of these trees, thus contributing to a more profound appreciation of their ecological significance and potential applications.

Comparison of two methods for assessing the pollen allergy risk of urban parks in Chengdu City, China

The urban green space is an important inducer of pollen allergy. In recent years, the incidence of pollen allergy in China has increased from 5 % to 17.8 %, and it still rapidly increases. However, only few assessment methods of pollen allergy risk have been developed and applied in the urban green spaces. The feasibility and the accuracies of the assessment results of these methods has been unknown. Therefore, in this paper, the two best-known methods, total pollen concentration monitoring method and urban green zone allergenicity index (IUGZA) method, were both used to assess the pollen allergy risk of the same urban park (the People’s Park of Chengdu City, China). The impact factors and prediction consistency of both models were compared. The results showed that the proportion of medium and highly allergenic tree species reached up to 75.93 % in People’s Park. The total IUGZA value of this park was 0.69. A total of 36,171 pollen grains were collected here. The average pollen concentration of this park was 125.88 grains/cm2 per day. Both methods showed that the pollen allergy risk of the People's Park was the highest in spring. Correlation analysis showed that no vegetation characteristics of this park were correlated with IUGZA values and total pollen concentration. However, pollen concentration was extremely significantly correlated with air temperature and solar radiation in autumn and winter. Kendall’s concordance coefficient identified a super high consistency between total pollen concentration and IUGZA values in this park. This result means that both methods for assessing the risk of pollen allergy are effective. Based on the total pollen concentration, a polynomial formula was established for succinctly calculating the IUGZA. A three-step greening strategy is proposed to minimize the volume of allergen production and increase the well-being of users of urban parks in Chengdu City.

Mapping of Allergenic Tree Species in Highly Urbanized Area Using PlanetScope Imagery—A Case Study of Zagreb, Croatia

Mapping and identifying allergenic tree species in densely urbanized regions is vital for understanding their distribution and prevalence. However, accurately detecting individual allergenic tree species in urban green spaces remains challenging due to their smaller site and patchiness. To overcome these issues, PlanetScope (PS) satellite imagery offers significant benefits compared with moderate or high-resolution RS imagery due to its daily temporal resolution and 3 m spatial resolution. Therefore, the primary objectives of this research were to: assess the feasibility of mapping allergenic tree species in the highly urbanized area using high-resolution PS imagery; evaluate and compare the performance of the most important machine learning and feature selection methods for accurate detection of individual allergenic tree species. The research incorporated three classification scenarios based on ground truth data: The first scenario (CS1) used single-date PS imagery with vegetation indices (VI), while the second and third scenarios (CS2 and CS3) used multitemporal PS imagery with VI, and GLCM and VI, respectively. The study demonstrated the feasibility of using multitemporal eight-band PlanetScope imagery to detect allergenic tree species, with the XGB method outperforming others with an overall accuracy of 73.13% in CS3. However, the classification accuracy varied between the scenarios and species, revealing limitations including the inherent heterogeneity of urban green spaces. Future research should integrate high-resolution satellite imagery with aerial photography or LiDAR data along with deep learning methods. This approach has the potential to classify dominant tree species in highly complex urban environments with increased accuracy, which is essential for urban planning and public health.

Atmospheric particulate matter deposition on birch catkins and pollen grains before pollination

Birch is the most allergenic tree species in Northern and Central Europe. Airborne birch pollen concentrations are observed to be on the rise for several decades. Health hazard due to birch pollen grains (BPGs) can worsen due to particulate air pollution. The prevalence of the intimate mixture of BPGs with atmospheric particulate matter (APM) at the single pollen grain level is still unraveled. In this study, APM transfer mechanisms to birch catkins and BPGs prior to pollination were investigated at an urban-industrial and a peri-urban site in Northern France. The surface of catkins was heavily polluted with micrometer-sized particles. Conversely, BPGs were relatively unpolluted with on average 0.1 particle.BPG−1. Differences in the chemical composition of adhered particles were observed as a function of the sampling sites. In contrast, no significant difference was found in terms of surface concentrations of APM adhered to BPGs and catkins between the two sites. Comparison of the number of particles deposited per pollen grain according to whether they were harvested from catkins or collected while airborne suggests that particulate pollution of pollen occurs preferentially after pollen shedding, either by impaction or coagulation mechanisms with other suspended APM or by pollen settling on dust-contaminated surfaces followed by resuspension.

Mapping abundance distributions of allergenic tree species in urbanized landscapes: A nation-wide study for Belgium using forest inventory and citizen science data

Mapping the distribution of allergenic plants in urbanized landscapes is of high importance to evaluate its impact on human health. However, data is not always available for the allergy-relevant species such as alder, birch, hazel, especially within cities where systematic inventories are often missing or not readily available. This research presents an approach to produce high-resolution abundance maps of allergenic tree species using existing forest inventories and opportunistic open-access citizen science data. Following a two-step approach, we first built species distribution models (SDMs) to predict species habitat suitability, using environmental characteristics as predictors. Second, we used statistical regressions to model the relationships between abundance, the habitat suitability predicted by the SDMs, and additional vegetation cover covariates. The combination of forest inventory data with citizen science data improves the accuracy of abundance distribution models of allergenic tree species. This produces a continuous, 1-hectare resolution map of alder, birch, and hazel showing spatial variations of abundance distributions both within the urban fabric and along the urban–rural gradient. Species abundance modelling can offer a better understanding of the existing and potential future allergy risk posed by green spaces and pave the way for a wide variety of applications at fine-scale, which is indispensable for evidence-based urban green space policy and planning in support of public health.

Establishing the twig method for investigations on pollen characteristics of allergenic tree species

The twig method in climate chambers has been shown to successfully work as a proxy for outdoor manipulations in various experimental setups. This study was conducted to further establish this method for the investigation of allergenic pollen from tree species (hazel, alder, and birch). Direct comparison under outdoor conditions revealed that the cut twigs compared to donor trees were similar in the timing of flowering and the amount of pollen produced. Cut twigs were able to flower in climate chambers and produced a sufficient amount of pollen for subsequent laboratory analysis. The addition of different plant or tissue fertilizers in the irrigation of the twigs did not have any influence; rather, the regular exchange of water and the usage of fungicide were sufficient for reaching the stage of flowering. In the experimental setup, the twigs were cut in different intervals before the actual flowering and were put under warming conditions in the climate chamber. An impact of warming on the timing of flowering/pollen characteristics could be seen for the investigated species. Therefore, the twig method is well applicable for experimental settings in pollen research simulating, e.g., accelerated warming under climate change.

Residential green space types, allergy symptoms and mental health in a cohort of tree pollen allergy patients

• We studied residential green space exposure of 157 adults with tree pollen allergy. • Residential green space was associated with reduced mental distress and perceived stress. • Allergenic tree species within 2 km distance contributed to mental distress. • Residential green space exposure was associated with more severe allergy symptoms. • Green space had mixed health effects during the pollination season.

Comparative proteomics of common allergenic tree pollens of birch, alder, and hazel.

BackgroundIn addition to known allergens, other proteins in pollen can aid the development of an immune response in allergic individuals. The contribution of the “unknown” protein allergens is apparent in phylogenetically related species where, despite of high homology of the lead allergens, the degree of allergenic potential can vary greatly. The aim of this study was to identify other potentially allergenic proteins in pollen of three common and highly related allergenic tree species: birch (Betula pendula), hazel (Corylus avellana) and alder (Alnus glutinosa).MethodsFor that purpose, we carried out a comprehensive, comparative proteomic screening of the pollen from the three species. In order to maximize protein recovery and coverage, different protein extraction and isolation strategies during sample preparation were employed.ResultsAs a result, we report 2500–3000 identified proteins per each of the pollen species. Identified proteins were further used for a number of annotation steps, providing insight into differential distribution of peptidases, peptidase inhibitors and other potential allergenic proteins across the three species. Moreover, we carried out functional enrichment analyses that, interestingly, corroborated high species similarity in spite of their relatively distinct protein profiles.ConclusionWe provide to our knowledge first insight into proteomes of two very important allergenic pollen types, hazel and alder, where not even transcriptomics data are available, and compared them to birch. Datasets from this study can be readily used as protein databases and as such serve as basis for further functional studies.

Tree pollen allergy risks and changes across scenarios in urban green spaces in Brussels, Belgium

Urban green spaces may improve human health and well-being. However, green spaces may also emit allergenic pollen and these may trigger asthma, allergic disease, and respiratory infections. How allergy risks in green spaces may be modified by environmental change is still not widely understood. This study analyzed tree inventory data of 18 urban green spaces (5940 trees; 278 taxa; 93 ha) in the Brussels Capital Region, Belgium. We investigated present tree pollen allergy risk (AR) and changes in AR driven by changes in tree species composition, allergenic potential and pollen season duration. AR was estimated by calculating the allergenicity index I UGZA (range 0–1, 1 worst) for the present situation and 13 scenarios.The average AR was 0.08 (SD 0.05; range 0.002–0.17). The AR increased by 11–27% in increased allergenic potential scenarios, and by 44% in the increased pollen season duration scenario. Preventive removal of birch, hazel and alder reduced the AR by 13%. The AR increased by 99–111% in combined scenarios with and without preventive removal of the main allergenic taxa.These findings indicate that tree pollen allergy risks could considerably rise when ongoing environmental changes lead to a combination of longer pollen seasons, increased pollen allergen potency, and increased sensitization for one or more species. The preventive removal of the main allergenic tree species cannot sufficiently counter allergy risks caused by other species and that are amplified by environmental change, highlighting the importance of careful tree species selection in urban green space policy and planning.

Tree Allergen Pollen-Related Content as Pollution Source in the City of Ourense (NW Spain)

Allergies became a major public health problem, identified as an important global pandemic with a considerable impact on the worldwide economy. In addition, a higher prevalence of pollen Type I sensitization cases in urban environments in comparison with the rural territories was detected. Our survey sought to assess the main biological pollution episodes caused by the aeroallergens of the major allergenic tree species in urban environments. A Hirst-type volumetric device was used for pollen sampling and a Burkard Cyclone sampler for the detection of tree atmospheric allergens over two years. The main allergens of Alnus, Fraxinus, Betula, Platanus and Olea, were detected in the atmosphere. Three peaks of important pollen concentrations were recorded throughout the year. The developed regression equations between pollen counts and allergen proteins registered great R2 values. The number of days with probability of allergenic symptoms was higher when the pollen and allergen data were assessed altogether. Fraxinus allergens in the atmosphere were detected using Ole e 1 antibodies and the Aln g 1 allergens with Bet v 1 antibodies, demonstrating the cross-reaction processes between the principal allergenic proteins of the Oleaceae and Betulaceae families. Long Distance Transport processes (LDT) showed that pollen from Betula populations located in mountainous areas increased the secondary peaks of pollen and allergen concentrations, and air masses from extensive olive orchards of North-Eastern Portugal triggered the highest concentrations in the atmosphere of Olea pollen and Ole e 1 allergens.

Deep Neural Network-Based Concentration Model for Oak Pollen Allergy Warning in South Korea.

PurposeOak is the dominant tree species in Korea. Oak pollen has the highest sensitivity rate among all allergenic tree species in Korea. A deep neural network (DNN)-based estimation model was developed to determine the concentration of oak pollen and overcome the shortcomings of conventional regression models.MethodsThe DNN model proposed in this study utilized weather factors as the input and provided pollen concentrations as the output. Weather and pollen concentration data were used from 2007 to 2016 obtained from the Korea Meteorological Administration pollen observation network. Because it is difficult to prevent over-fitting and underestimation by using a DNN model alone, we developed a bootstrap aggregating-type ensemble model. Each of the 30 ensemble members was trained with random sampling at a fixed rate according to the pollen risk grade. To verify the effectiveness of the proposed model, we compared its performance with those of models of regression and support vector regression (SVR) under the same conditions, with respect to the prediction of pollen concentrations, risk levels, and season length.ResultsThe mean absolute percentage error in the estimated pollen concentrations was 11.18%, 10.37%, and 5.04% for the regression, SVR and DNN models, respectively. The start of the pollen season was estimated to be 20, 22, and 6 days earlier than that predicted by the regression, SVR and DNN models, respectively. Similarly, the end of the pollen season was estimated to be 33, 20, and 9 days later that predicted by the regression, SVR and DNN models, respectively.ConclusionsOverall, the DNN model performed better than the other models. However, the prediction of peak pollen concentrations needs improvement. Improved observation quality with optimization of the DNN model will resolve this issue.

Residential green space and seasonal distress in a cohort of tree pollen allergy patients.

Residential green space may improve human health, for example by promoting physical activity and by reducing stress. Conversely, residential green space may increase stress by emitting aeroallergens and exacerbating allergic disease. Here we examine impacts of exposure to residential green space on distress in the susceptible subpopulation of adults sensitized to tree pollen allergens. In a panel study of 88 tree pollen allergy patients we analyzed self-reported mental health (GHQ-12), perceived presence of allergenic trees (hazel, alder, birch) near the residence and residential green space area within 1 km distance [high (≥3 m) and low (<3 m) green]. Results were adjusted for patients' background data (gender, age, BMI, smoking status, physical activity, commuting distance, education level, allergy medication use and chronic respiratory problems) and compared with distress in the general population (N = 2467). Short-term distress [mean GHQ-12 score 2.1 (95% confidence interval 1.5-2.7)] was higher in the study population than in the general population [1.5 (1.4-1.7)]. Residential green space had protective effects against short-term distress [high green, per combined surface area of 10 ha: adjusted odds ratio OR = 0.94 (95% confidence interval 0.90-0.99); low green, per 10 ha: OR = 0.85 (0.78-0.93)]. However, distress was higher in patients who reported perceived presence of allergenic trees near their residence [present vs. absent: OR = 2.04 (1.36-3.07)]. Perceived presence of allergenic tree species in the neighbourhood of the residence of tree pollen allergy patients modulates the protective effect of residential green space against distress during the airborne tree pollen season.

Residential green space and mental health in a prospective cohort of tree pollen allergy patients

GREEN, AIR, LMIC: PECHAKUCHA COMES TO ISEE! Johan Friso Foyer, Floor 1, August 27, 2019, 10:30 AM - 12:00 PM BACKGROUND: Green space may improve human health, for example by promoting physical activity and by reducing stress. Conversely, green space may exacerbate the burden of allergic disease by emitting aeroallergens. OBJECTIVES: We examined whether residential exposure to green space had impacts on mental health in adults sensitized to tree pollen allergens during two airborne tree pollen seasons (2017, 2018). METHODS: In this cross-sectional study, data from a prospective Belgian cohort of tree pollen allergy patients (N = 88) were analyzed using Poisson regression. The primary outcome was self-reported mental health, assessed with the standardized 12-item General Health Questionnaire (GHQ-12). Predictors of distress included perceived presence of allergenic trees near the residence (hazel, alder, birch) and cumulative green space area within 1 km distance. Results were compared to distress in a representative sample of the general population (N = 2,467). RESULTS: Short-term distress [mean GHQ-12 score 2.1 (95% confidence interval 1.5–2.7)] was higher in the study population than in the general population [1.5 (1.4–1.7)]. Distress increased with BMI {adjusted odds ratio [95% confidence interval] 1.06 (1.02–1.10)}, smoking [2.10 (1.02–4.38)] and perceived presence of allergenic trees [2.04 (1.36–3.07)]. Physical activity [>1×/week 20 minutes of activity vs. less: 0.59 (0.42–0.85)], age [0.97 (0.96–0.99)] and green space [≥ 3m tall, per combined surface area of 10 ha: 0.94 (0.90–0.99); < 3m tall, per 10 ha: 0.85 (0.78–0.93)] had protective effects against short-term distress. CONCLUSIONS: The perceived proximity to allergenic tree species modulates the protective effect of residential green space against short-term emotional distress during the airborne pollen season. Negative expectations of adults sensitized to tree pollen allergens regarding exposure to allergenic tree species may affect short-term mental health outcomes during the pollen season.

Prisustvo otrovnih drvenastih vrsta na zelenoj površini vrtića 'Suncokreti' u naselju Višnjička Banja, Beograd

On the green areas preschools and schools can find a variety of woody species, among which there are invasive, allergenic and toxic. Toxic woody species differ in their degree of toxicity. In the case of maturity in the human body of a toxic plants can cause minor, some major disruptions, and some can even lead to death. Toxic woody and shrub species are not desirable in the green areas of school and especially pre-school institutions. Despite numerous poisonous woody and shrub species are found in them, which can pose a serious threat to the health of children. The aim was to determine the presence of poisonous trees and shrub species on the surface of the green kindergarten 'Sunflowers' in the suburb Višnjička banja in Belgrade. The studies were conducted on the green area kindergarten 'Sunflowers' in the suburb Višnjička banja in Belgrade. Determination of trees and shrub species was determined according Vukicevic (1996), and Ocokoljić Ninić-Todorović (2003), Šilic (1990), Cvjetićanin and Perovic (2010). Toxic woody species are separated according Grlić (1984), Frohne, Pfänder (1997), Ivanić et al., (1996). The degree of toxicity was determined according to the type of Ivanić et al., (1996) and Frohne, Pfänder (1997). In relation to whether cause mild, severe or very severe fatal poisoning in case of entry into the body, ascertained poisonous species are divided into conditionally toxic, toxic, very toxic, and types that cause very serious, fatal poisoning. Depending on the size of wood, flowers, fruits and seeds can be more or less accessible to children, and for that reason the diameter of the elements carried by tree growth Banković and Pantić (2006). In the courtyard of the kindergarten 'Sunflowers' was recorded 26 tree species with 227 trees. There are also five species of bush habit, as well as two climbing plants. Of the total of 26 woody species 6 is one of those whose individual parts or the whole plant-toxic (Thuja orientalis, Laburnum anagyroides, Robinia pseudoacacia, Rhus typhina, virgilliana Quercus, Aesculus hippocastanum). Of the five species of woody bushy habit, 3 species belong to the poisonous (Taxus baccata, Prunus laurocerasus, Ligustrum vulgare). Differences were two poi- sonous climbing plants (Hedera helix, Clematis vitalba). In total there are 11 toxic species. It was noted that all poisonous species recorded in the studied area, or their toxic components in more or less accessible to children, and it is accordingly necessary caution educators, and education in terms of recognition of these species and to react in case of an incident. Toxic planting trees and shrub species in parks and other green areas is not necessary to avoid, but it is certainly not desirable to cultivate them in places such as school and pre-school yard where they were always available to children. Better knowledge of poisonous plants, with proper precautions can minimize the number of poisoning. Also, during the planning and design, except toxic, it would be desirable not to predict invasive and allergenic tree species in green areas nursery.

Tree pollen allergens-an update from a molecular perspective.

It is estimated that pollen allergies affect approximately 40% of allergic individuals. In general, tree pollen allergies are mainly elicited by allergenic trees belonging to the orders Fagales, Lamiales, Proteales, and Pinales. Over 25 years ago, the gene encoding the major birch pollen allergen Bet v 1 was the first such gene to be cloned and its product characterized. Since that time, 53 tree pollen allergens have been identified and acknowledged by the WHO/IUIS allergen nomenclature subcommittee. Molecule‐based profiling of allergic sensitization has helped to elucidate the immunological connections of allergen cross‐reactivity, whereas advances in biochemistry have revealed structural and functional aspects of allergenic proteins. In this review, we provide a comprehensive overview of the present knowledge of the molecular aspects of tree pollen allergens. We analyze the geographic distribution of allergenic trees, discuss factors pivotal for allergic sensitization, and describe the role of tree pollen panallergens. Novel allergenic tree species as well as tree pollen allergens are continually being identified, making research in this field highly competitive and instrumental for clinical applications.

A clinically relevant major cross‐reactive allergen from mesquite tree pollen

Prosopis juliflora (mesquite) is one of the major sources of pollinosis in tropical and semi-arid countries of the world. The present study was undertaken to purify and characterize a major cross-reactive allergen from this tree species. Mesquite pollen extract was purified using reverse-phase chromatography. Allergen characterization was done by electrophoresis, enzyme-linked immunosorbent assay (ELISA) and Western blotting. Clinical relevance of the purified protein was analyzed by in vivo (skin tests) and in vitro experiments such as ELISA, histamine release, peripheral blood mononuclear cells (PBMC) proliferation and cytokine assays. Cross-reactivity of purified protein with allergenic tree species and lima bean (food) was assessed by inhibition assays. A 66-kDa protein was purified from mesquite pollen extract using octadecyl silica resin. Purified protein recognized 90% of mesquite-sensitized patients in skin test and ELISA. It induced significant histamine release in allergic patients' blood and interleukin-4 secretion in the PBMC culture supernatants. Inhibition assays suggested close allergenic relationship of this protein with Ailanthus excelsa, Cassia siamea, Salvadora persica pollen and Phaseolus lunatus (lima bean - an edible legume). A 66-kDa major cross-reactive allergen was isolated from mesquite pollen using single-step purification procedure. The protein seems relevant for clinical applications in allergic disorders.

A long-term study of winter and early spring tree pollen in the Tulsa, Oklahoma atmosphere

Since 1986 the atmosphere in Tulsa, Oklahoma has been monitored for airborne pollen and spores with a Burkard 7-day spore trap situated on the roof of a building at The University of Tulsa. The present study specifically examined the early spring tree pollen season for several local taxa and the occurrence of pre-season pollen during December and January. Knowledge of the local pollen season will help identify the presence of out-of-season pollen and possible long distance transport (LDT) events. Average daily concentrations of airborne pollen for species ofBetula, Quercus, Ulmus, and Cupressaceae were determined for each year from 1987 to 1996. The data showed that during the early spring the precise pollination periods for these allergenic tree species are highly variable. There were considerable variations in start date, season length, peak concentration, date of peak, and cumulative season total. The start dates forUlmus, Betula, andQuercus varied by 30 days or more, while the early spring Cupressaceae pollen showed the least variation in start date (only 23 days). More research is needed to understand the mechanisms which govern the onset and magnitude of pollen release. Although several reports have documented episodes of long distance transport (LDT) of pollen, the actual contribution of out-of-season or out-of-region pollen to local air spora is poorly known. The current study also re-examined the LDT ofJuniperus ashei pollen in Oklahoma.Juniperus pollen appeared in the Tulsa atmosphere on 40% of the days in December and January with concentrations as high as 2400 pollen grains/m3 of air; however, no local populations ofJuniperus pollinate at this time of the year. High concentrations occurred on days with southerly winds suggesting thatJuniperus ashei populations in southern Oklahoma and Texas were the pollen source. Since no local pollen is present in the Tulsa atmosphere in December and January, this example of LDT has been easy to document.