Search Results (552)

Despite the undisputable ecosystem importance of honeybees, human activities have a substantial impact on their health. Since foraging is directly linked to a wide range of crops and bee-attracting flowers, plant protection products are at the forefront of chemical scrutiny, along with contamination of pollen, nectar, beehive components and water by other xenobiotics. In this study, a non-targeted Liquid Chromatography-High-Resolution Mass Spectrometry (LC-HRMS) screening was applied to 25 honeybee samples collected after reported death incidents in Greece. This approach led to the tentative annotation of over 50 compounds across various chemical classes, including pesticides, PFAS candidates not included in the EFSA “PFAS-4”, pharmaceuticals, antibiotics, industrial chemicals, and natural product constituents. In parallel, targeted pesticide residue analysis using liquid and gas chromatography coupled to tandem mass spectrometry (LC-MS/MS and GC-MS/MS) was performed, covering more than 250 active substances and providing direct quantitative results, revealing 11 active substances in concentrations ranging from <limit of quantification (LOQ) to 0.95 mg/kg, overlapping substantially with the HRMS detection. Overall, this study does not allow concrete causal attribution of mortality to specific chemicals; however, it documents complex co-occurrence patterns (pesticides together with other xenobiotics and plant bioactives), not excluding sublethal and mixture-toxicity effects. Quantified pesticide concentrations were below acute LD50-based thresholds, yet selected samples combined neonicotinoid/pyrethroid/fungicide signatures and other contaminants, supporting the need for mixture-toxicity frameworks and effect-based follow-ups. Full article

Adequate pollination of pollinator-dependent crops relies on the abundance and diversity of pollinators, and any temporal mismatch can lead to decreased productivity. Induced off-season flowering is widely used to anticipate the blooming time and to have a favorable market to generate greater economic income. However, the relationship between off-season flowering, effective pollination, and crop yield remains poorly understood. In this study, we compared pollinator and yield metrics of mango among its natural and off-season flowering across two years. We found that the composition, richness, and abundance of their effective pollinators varied across flowering seasons. Remarkably, blowflies were the floral visitors that deposited the highest number of pollen grains per visit and were the most important pollinators during the off-season, while honeybees and stingless bees were more important in the natural season. Mango yield was more positively related to the abundance of wild pollinators in both seasons than to honeybees. However, in both flowering seasons, mango trees suffered from pollen limitation and had a high incidence of malformed fruits. These findings highlight the important role of wild pollinators in maintaining and improving the mango yield and quality, mainly during the induced flowering season, improving the income to mango producers and increasing food security. Full article

Understanding how pollinators adjust their behavior to maximize reproductive success in resource-limited desert ecosystems is a fundamental ecological question. In this study, we investigated X. mongolicus using a combination of field behavioral observations, pollen identification, nutritional analysis, and morphometric measurements to systematically examine interannual variations in its flower visitation spectrum, foraging behavior, bee bread composition, and offspring body size. Our findings reveal a striking contrast: although this species exhibits polyphagy in flower visitation, it shows dietary specialization in larval nutrition—over 92% of the pollen in its bee bread originates from just two leguminous species, A. mongolicus and O. bicolor. Foraging duration increased with rising temperature and humidity, and bees adapted to strong winds by flying close to the ground. Compared with 2024, the bee bread in 2025 had lower fresh weight but higher crude protein content, and offspring body size was larger—likely due to more abundant spring rainfall in 2025, which improved the flowering performance of A. mongolicus. Collectively, these results indicate that this bee species copes with resource uncertainty in desert habitats through flexible foraging range and highly specialized food storage, with its reproductive success closely tied to the nutritional supply of key plants and precipitation patterns. This study highlights the role of precipitation timing in shaping the nutritional foundation of plant–pollinator interactions, providing a scientific basis for the conservation and management of desert pollinators. Full article

While the gut microbiota of pollen-carrying bees (e.g., honeybees and bumblebees) has been well studied, the gut microbiota of vespine wasps remains poorly understood. Unlike pollen-carrying bees, which primarily consume pollen and nectar, vespine wasp larvae mainly feed on insects, suggesting that their gut bacterial communities may be different. Therefore, this study aimed to reveal the differences in larval gut bacterial communities between pollen-carrying bees and vespine wasps. Using datasets obtained from our own samplings and public resources released by other researchers, we compared the diversity and composition of larval gut bacterial communities between vespine wasps and pollen-carrying bees. Alpha diversity and beta diversity of bacterial communities were measured. Results showed that vespine wasp larvae harbored distinct gut bacterial communities from those of pollen-carrying bees, dominated by Leuconostoc, Hafnia-Obesumbacterium and Lactobacillus. Significant differences in bacterial composition were observed at both the community level and the dominant taxa level between pollen-carrying bee larvae and vespine wasp larvae. Moreover, significant differences were also found among larval gut bacteria of vespine wasps. These findings provide insights into the bacterial composition of aculeate wasps with different dietary habits. Full article

As the predominant native pollinator across Asia, Apis cerana is essential for the maintenance of biodiversity and agricultural productivity. The gut microbiota of honeybees plays a central role in host nutrition, detoxification, and immune function. p-Coumaric acid, a widespread phenolic acid enriched in pollen and nectar, has been reported to promote honeybee health by prolonging lifespan and increasing the expression of detoxification-related genes, hence improving tolerance to pesticides. Its influence on gut microbial communities, however, remains insufficiently characterized in A. cerana. This study evaluated the effects of dietary p-coumaric acid on survival, sucrose solution consumption, and gut microbiome composition in A. cerana workers using absolute quantification sequencing. Bees were provided sucrose solutions containing p-coumaric acid at concentrations of 41.0, 82.0, and 164.0 mg/L for durations of 5 and 10 days. The results indicated no effect on survival but revealed time-dependent changes in sucrose solution consumption. p-Coumaric acid exposure altered the abundance of non-core bacterial taxa, including Bombella and Apilactobacillus, whereas the core gut microbiota (Lactobacillus, Gilliamella, Snodgrassella, Apibacter, and Bifidobacterium) remained stable. These results suggest that p-coumaric acid modulates sucrose solution consumption and selectively influences non-core gut bacteria without disrupting survival or core microbiota stability, underscoring its role in regulating host–microbe interactions in honeybees. Full article

Melissopalynological analysis is essential for determining the botanical origin of honey, corbicular pollen and bee bread, as well as detecting adulteration. However, it traditionally relies on labor-intensive and subjective manual pollen identification. As a proof-of-concept preceding full honey analysis, this study evaluates artificial intelligence methods for automated pollen grain recognition under controlled conditions. Hazel (Corylus avellana L.) and dandelion (Taraxacum officinale F.H. Wigg.) were used as model taxa to validate the proposed approach before its application to real varietal honey samples. This study introduces a novel three-stage pipeline that decouples object detection from feature extraction, utilizing YOLOv12m for region-of-interest generation and, for the first time in melissopalynology, DINOv3 ConvNeXt-B for deep feature representation. Microscopic images acquired at 400× magnification yielded 2498 dandelion and 1941 hazel pollen grains. The detector achieved an mAP@0.5 of 0.936 with an F1 score of 0.88, while the classifier reached 98.1% accuracy with good class separability (Silhouette coefficient: 0.407). The primary technical contribution is the systematic optimization of the detection-to-classification interface. Context-aware bounding box expansion (12%) and an optimized IoU-NMS threshold (0.65) significantly improve the stability of morphological feature extraction, as confirmed by ablation studies. Computational cost reporting further supports reproducible, deployment-oriented comparison. The results confirm the feasibility of this AI-based framework as an intermediate step toward automated melissopalynological analysis, with future work focusing on standardized microscopy protocols and expanded pollen databases for varietal honey authentication. Full article

Insects underpin key ecosystem services. Yet tree-associated insect communities remain comparatively poorly documented, particularly in temperate forests. This study aimed to characterize the diversity and abundance of insect assemblages associated with the predominantly insect-pollinated forest tree Tilia cordata Mill. in protected areas in Lithuania, and to assess the occurrence of known and putative pollinator groups within these assemblages. We quantified insect assemblages associated with Tilia cordata using two sampling methods but did not directly measure pollination effectiveness (e.g., pollen loads, visitation rates to flowers, or fruit/seed set). Consequently, our inferences refer to the presence and composition of potential pollinators rather than demonstrated pollination function or realized pollination services. Fieldwork was conducted over two years in six protected T. cordata sites in Lithuania using two complementary sampling methods: net sampling and sticky traps. Sampling was structured into three observation periods corresponding to T. cordata phenology: pre-flowering (I), flowering (II) and post-flowering (III). In total, 207 insect taxa from 15 orders were recorded by net sampling and 86 taxa from 11 orders by sticky traps. Net sampling showed significantly higher diversity (Shannon H = 3.81) than sticky traps (H = 2.10). Hemiptera, Coleoptera and Diptera were the most common groups, and most taxa occurred at low to moderate abundances, with only a few species showing local dominance in specific periods or sites. Taxa documented in the literature as significant pollinators were consistently present but at low relative abundances (about 5–10% in total). Insect assemblage composition and species proportions varied among phenological periods and between years, with no clear, consistent peak in overall insect abundance or diversity associated specifically with the T. cordata flowering phase. These findings indicate that T. cordata stands in protected areas harbor diverse insect assemblages typical of temperate deciduous and mixed forest habitats and include a broad spectrum of non-bees and other potential pollinators. Therefore, we did not detect a distinct peak in insect abundance or species richness during the T. cordata flowering period, indicating that flowering did not coincide with a pronounced maximum in pollinator-related insect activity. However, the quantitative patterns observed suggest that, in this context, T. cordata provides only modest support for pollinator guilds, and its role is better interpreted as one component of wider forest insect diversity rather than as a primary driver of pollination services. Full article

Phenolamides in bee pollen exhibit notable bioactivities, such as antioxidant, anti-inflammatory, and antimicrobial effects. Ulcerative colitis (UC) is a prevalent intestinal disorder, while the potential effects of phenolamides on UC remain unclear. This study aims to investigate the effects and mechanisms of phenolamide extract (PAE) from apricot bee pollen on dextran sulfate sodium (DSS)-induced UC in mice. Firstly, we analyzed the main compounds of PAE. Mice were treated with PAE (100, 200, and 400 mg/kg bw) both during the 7 days preceding 2.5% DSS induction and throughout the induction period (7 days). The results show that the primary compounds of PAE were isomers of tri-p-coumaroyl spermidine (97.78 ± 2.76%). A biochemical analysis showed that PAE decreased the levels of pro-inflammatory cytokines and increased the activities of antioxidant enzymes. Regarding the gut microbiota, PAE reduced the Bacillota/Bacteroidota ratio. Additionally, PAE elevated beneficial bacteria, including norank_f_Muribaculaceae, norank_o_Clostridia_UCG-014, and Lachnospiraceae_NK4A136_group, while reducing harmful bacteria, including Escherichia-Shigella, Clostridium, and Romboutsia. A quantitative analysis of short-chain fatty acids (SCFAs) demonstrated that PAE intervention promotes the biosynthesis of SCFAs in UC mice. This study first demonstrates that PAE attenuates DSS-induced colitis by modulating gut microbiota and SCFAs, suggesting its potential as a functional dietary supplement for colitis. Full article

Bee pollen is an extraordinary nutritional product of honeybees. Its valuable profile depends on the concentration of bioactive compounds, influenced by multiple factors, such as geographical origin and botanical species. Pollen samples produced by a single farm and collected during four different seasonal periods were first subjected to palynological analysis and then evaluated for their volatile profile and the content of selected nutraceutical compounds. The June sample, characterized by a high percentage of Castanea pollen, exhibited the higher concentration of soluble sugars, proteins, antioxidant molecules and minerals. The heatmap and hierarchical clustering confirmed a pronounced seasonal variability in bee pollen volatile composition, strongly linked to changes in floral availability. The greatest dissimilar volatilomic fingerprints are represented by samples collected in November (monofloral pollen of Hedera helix) and April (polyfloral pollen). The seasonal variability on the bioactive compounds, as well as in aromatic composition, seem to be linked to the different compositions of plant pollen, related to its botanical origin. This study expands current knowledge on the chemical characterization of bee pollen and supports the use of volatilome analysis as a complementary tool to palynological investigation for assessing botanical origin, quality, and the ecological and sensory value of this bee product. Full article

This study examined nectar and pollen production as well as pollinator visitation in Nigella damascena (Ranunculaceae), an annual ornamental and seed crop, over two flowering seasons. Flower anthesis lasted 6–7 days, with protandry: the male phase began on the first day, and pollen presentation continued until corolla senescence. Peak stigma receptivity occurred in 5-day-old flowers, resulting in a partial overlap of male and female functions between days 5 and 7. Nectar was secreted by petal-derived structures, with secretion beginning in 1-day-old flowers and steadily increasing, peaking on the day of maximum stigma receptivity. The nectar sugar composition differed between floral phases; it was sucrose-dominant in the male phase and sucrose-rich in the female phase. Significant year effects were observed for flowering abundance, nectar traits (volume, sugar production, concentration), and pollen output. Flowers were visited predominantly by honey bees, but bumblebees, solitary bees, and dipterans were also recorded. These results demonstrate that floral reward traits vary between years and contribute to differences in the temporal availability of nectar and pollen resources. Full article

Bee pollen is a natural product with multifunctional properties, containing abundant bioactive compounds, especially phenolic acids and flavonoids, which are largely responsible for its antioxidant and antimicrobial activities. In this study, the bioactive composition, antioxidant capacity, encapsulation efficiency, antimicrobial activity, and gastrointestinal stability of bee pollen extract (PE) were investigated. The pollen extract exhibited high total phenolic (2817 mg GAE/100 g) and flavonoid contents (5255 mg QE/100 g), along with strong antioxidant activity (DPPH: 4305 mg TE/100 g; CUPRAC: 3685 mg TE/100 g). To improve the stability and bioaccessibility of phenolic compounds, PE was encapsulated using β-cyclodextrin (BCD) at different weight ratios. Among the formulations, the PE:BCD ratio of 1:2 showed the highest encapsulation efficiency (64%) and favorable physicochemical properties, including higher particle size and more negative zeta potential values, indicating good colloidal stability. Antimicrobial activity was evaluated for PE, BCD-only, and the selected PE-loaded formulation (1:2, w:w). Encapsulation led to a modest reduction in antimicrobial activity compared to free PE (6.25–50 mg/mL); however, the encapsulated formulation still exhibited considerable antibacterial effects against both Gram-positive and Gram-negative strains (25–50 mg/mL). Furthermore, in vitro gastrointestinal digestion indicated that BCD encapsulation substantially enhanced the bioaccessibility of total phenolics (81%) and antioxidant capacity (DPPH: 48%; CUPRAC: 76%), particularly during the intestinal stage. Phenolic profiling showed that chlorogenic acid and quercetin derivatives remained relatively stable throughout digestion. Overall, encapsulation with BCD effectively safeguarded pollen phenolics, improved their gastrointestinal stability, and increased bioaccessibility, highlighting the potential of encapsulated bee pollen as a functional food ingredient or nutraceutical. Full article

The endemic Minuartia nifensis, the only known gynodioecious species of its genus, offers a suitable model for understanding the relationships between floral characteristics, pollination, and mating systems in species with narrow distributions and single populations. We analyzed population structure, floral morphology, pollen viability, stigma receptivity, mating system components, and pollinator assemblages using field observations, morphometric measurements, controlled pollination experiments (autogamy, allogamy, apomixis and open pollination), and standardized pollinator surveys. The population exhibited an approximately balanced hermaphrodite–female ratio (0.97:1) and clear sexual dimorphism, with hermaphrodite flowers significantly larger than female flowers. Despite this dimorphism, pollinator visitation was similar between morphs, with 52.54% of visits to hermaphrodite flowers and 47.46% to female flowers. A total of 1734 visits by seven visitor species were recorded, of which approximately 95% of potentially effective pollen transfer was attributable to three bee taxa. Pollen viability, stigma receptivity, and visitation frequency peaked between 12:00 and 14:00, accounting for 58% of total insect visits. Controlled pollination experiments showed highest reproductive success under cross-pollination and limited success under self-pollination, indicating a mixed but predominantly outcrossing mating system. Together, these results suggest that gynodioecy in M. nifensis may be supported by floral differentiation, temporal reproductive traits, and pollinator-mediated pollen transfer. Full article

Environmental toxins can impair gut microbiota and increase intestinal permeability, contributing to various health problems. While many such toxins are known to disrupt tight junctions and compromise barrier function, research specifically examining carbon tetrachloride (CCl₄) as a trigger of intestinal epithelial barrier dysfunction remains limited. In this study, 54 young Western albino male rats, weighing 180–200 g, were randomly assigned to nine experimental groups, each comprising six rats. Group 1 received 1 mL of oral saline and served as a control. Groups 2 and 3 received 0.2 g/kg body weight probiotic and prebiotic, respectively, for four weeks. CCl₄ (1 mL/kg, i.p.) was administered either at the beginning of day 1 (damage induction; Group 4) or at the end of day 28 (protection assessment; Group 7). Intervention groups received probiotics and prebiotics for 4 weeks after (therapeutic) CCl₄ exposure on day 1 in Groups 5 and 6, respectively. Groups 8 and 9 received probiotics and prebiotics for 4 weeks before CCl₄ exposure on day 28, respectively. Quantification of gut bacterial populations, serum levels of Occludin and Zonulin, as biomarkers of intestinal permeability, and histopathological analysis of intestinal tissue were conducted. CCl₄ induces significant intestinal epithelial barrier dysfunction with marked histopathological alterations. Probiotic treatment was more effective than prebiotics at normalizing serum Zonulin and Occludin levels in CCl₄-induced intestinal damage. Probiotics restore microbial balance by suppressing the overgrowth of pathogenic organisms, while prebiotics confer partial protection. CCl₄-induced gut barrier disruption is restored through probiotic supplements by restoring gut microbial balance and normalizing tight junction-associated biomarkers. Full article

Leucania loreyi (Duponchel, 1827) is a major lepidopteran pest that infests a wide range of crops worldwide. Effective mass production of insects for pest management programs depends on the availability of suitable artificial diets. Here, we evaluated 14 artificial diets (D1–D14) formulated from maize or cowpea seeds (19.5 g) plus standard diet components and supplemented with 1 g of pollen from different sources (rapeseed, date palm, maize, common hollyhock, saffron, and honey bee), along with control diets. We assessed their effects on demographic traits of L. loreyi. The maize seed–maize pollen diet (D3) and the cowpea seed–maize pollen diet (D10) produced the shortest developmental times (37.53 and 38.10 days, respectively), whereas the maize seed–saffron pollen (D5) and cowpea seed–saffron pollen (D12) diets resulted in the longest development (45.83 and 45.56 days, respectively). Diet also D3 yielded the shortest adult and total pre-oviposition periods (APOP and TROP), the greatest female longevity, and the highest fecundity and net reproductive rate (R₀) (801.69 and 88.69 offspring, respectively). In contrast, diet D12 produced the lowest fecundity and R₀ (339.73 and 68.15 offspring, respectively). Consistent with these patterns, D3 generated the highest intrinsic rate of increase (r) and finite rate of increase (λ), while diets D5 and D12 were associated with lower population growth rates. Cluster analysis further identified D3 as the most nutritionally favorable formulation under our experimental conditions, supporting its potential utility for large-scale L. loreyi rearing. Full article

Bee pollen is a complex biological matrix whose functional quality results from the interaction between botanical origin, phenolic composition and antioxidant activity. The aim of this study was to integrate palynological, chemical and antioxidant data through composite functional indices and multivariate analysis to characterize the functional quality of 24 Spanish bee pollen samples. Palynological analysis, phenolic profiling and antioxidant assays (DPPH, ABTS^+• and FRAP) were combined with biodiversity metrics to construct a Phenolic Index (PI), an Antioxidant Index (AI) and a Global Functional Index (GFI). Spearman correlation analysis, principal component analysis (PCA) and one-way ANOVA were applied for index validation and interpretation. Strong correlations were observed between AI, GFI, total phenolic content, and antioxidant assays, confirming the robustness of the composite indices. PCA revealed a dominant functional–antioxidant gradient primarily driven by the dominant botanical origin. Samples dominated by Castanea and Rubus showed higher functional indices, whereas those dominated by Cistaceae exhibited lower functional performance. ANOVA confirmed that dominant pollen type significantly affected most physicochemical, antioxidant and functional variables, while palynological diversity indices showed no significant influence. The integrative multivariate approach provides a robust framework for functional quality assessment of bee pollen, supporting authentication, quality control and the development of functional products. Full article