Search Results (177)

Essential oils obtained from Siparuna plants, e.g., S. guianensis and S. gesnerioides, have potential for use as biorational insecticides. However, the activities of S. gesnerioides oils remain largely unexplored compared to S. guianensis oils. Using an integrative approach combining toxicological bioassays, geometric morphometrics, and in silico modeling, we assessed the adulticidal potential, selectivity, and the effects of early-life exposure to these oils on the larval susceptibility and adult wing morphometry of Aedes aegypti. Adulticidal assays revealed high toxicity, with S. guianensis (LC₅₀ = 15.0 nL/mL) being 15-fold more potent than S. gesnerioides (LC₅₀ = 233.0 nL/mL). Beyond acute lethality, early-life (i.e., eggs to L2 larvae) exposure to sublethal concentrations (S. guianensis = 7.4 nL/mL and S. gesnerioides = 118.0 nL/mL) was associated with wing morphometric disruptions and increased fluctuating asymmetry in Ae. aegypti adults, especially in those exposed to S. gesnerioides essential oil. Furthermore, early-life exposure to S. gesnerioides modulated L4 larvae susceptibility, which was associated with lower mortality in subsequent exposures. Selectivity assays demonstrated low acute oral toxicity in initial laboratory screenings with Apis mellifera, while molecular docking approaches predicted higher affinity of bicyclogermacrene and α-copaene for Ae. aegypti TRPV channels. Collectively, while S. gesnerioides oil was less acutely toxic, early-life sublethal exposures reduced fourth instar larvae (L4) susceptibility, which may have contributed to developmental instability and morphological alterations in adults. Our findings highlight the potential of Siparuna essential oils in mosquito management by impacting mosquito fitness beyond acute mortality. Full article

Honeybee (Apis mellifera) health is governed by the integrated action of detoxification, immunity, and microbiota within complex environmental contexts. The coordinated detoxification system (DETOXome), primarily active in the midgut, fat body, and Malpighian tubules, includes cytochrome P450s, glutathione S transferases, carboxylesterases, and ABC transporters, and functions in concert with innate immune pathways such as Toll, Imd, Jak/STAT, JNK, antimicrobial peptides, and RNA interference. Cellular maintenance mechanisms, including heat shock proteins, proteostasis, and antioxidant defenses, support these systems under chemical, thermal, and pathogen-induced stress. Multi-stressor exposures encompassing pesticides, pathogens, nutritional limitations, and climate variations interact to affect physiological resilience, behavior, and colony function. This review synthesizes molecular, organ-specific, and colony-level evidence to provide a mechanistic framework connecting environmental stressors to detoxification and immune responses. Predictive markers derived from transcriptomic, proteomic, and microbiome analyses offer early detection of sublethal stress, while genomic and selective breeding strategies hold the potential to enhance honeybee resilience. By integrating stress pathways across biological scales, this review advances a unified model of honeybee health that moves beyond descriptive lists to highlight cross-system interactions driving colony survival. Full article

Beekeepers widely recognize Varroa destructor (Mesostigmata: Varroidae) as one of the most serious threats to honey bee (Apis mellifera) health. To control V. destructor, beekeepers routinely use chemical treatments that reduce mite populations, benefiting colonies. However, these treatments also expose honey bees to compounds that may cause unintended harm. Honey bees and V. destructor share biological structures that are targeted by acaricides. In this review, we describe the main modes of action of commonly used synthetic and natural chemicals and discuss differences between mites and honey bees that explain selectivity. In addition, exposure to non-lethal doses can potentially disrupt honey bee functions outside the treatment’s primary targets. Here, we synthesize current knowledge on the effects of V. destructor control chemicals on honey bee health at the molecular level, the individual level (including larvae, workers, queens, and drones), and the colony level. Unfortunately, not all tissues and colony functions have been studied for every compound. Therefore, this review also identifies knowledge gaps where the effects are still unknown. We believe that a better understanding of the effects of V. destructor treatments on honey bee colonies will help beekeepers manage these treatments more carefully, benefiting both beekeepers and honey bees. Full article

Antimicrobial resistance (AMR) is a growing global concern, exacerbated by the overuse of antibiotics in livestock farming. Honey bees (Apis mellifera), widely used as bioindicators of environmental contamination, may also serve as sentinels for monitoring the environmental spread of antibiotic resistance genes (ARGs). This study investigated the presence of ARGs and the gut microbiota composition of honey bees sampled from 11 apiaries located in a region of Northwestern Italy characterized by intensive livestock farming. PCR and Sanger sequencing analyses revealed a widespread presence of tetracycline resistance genes—particularly tetB and tetC—as well as occasional detection of blaTEM, qnrB, and int1 genes. tetB and tetC were also identified in three bacterial colonies isolated from bee guts, notably in Hafnia spp. 16S rRNA gene sequencing of the gut microbiota revealed dominance of genera such as Bartonella, Snodgrassella, Gilliamella, Bombilactobacillus, and Lactobacillus. Some samples showed shifts in the microbial diversity. The findings confirm the potential of honey bees as bioindicators for environmental AMR surveillance and underscore the need for further research to elucidate correlations between ARG presence and microbial community structure in honey bees from various ecological contexts. Full article

Honey bees rely on a specialized gut microbiota for nutrition, detoxification, and immune function, yet the effects of emerging insecticides on this symbiotic system remain poorly understood. We compared the acute toxicity and short-term gut microbiota responses of Apis mellifera ligustica workers exposed to two insecticides with contrasting toxicity classes: the highly toxic emamectin benzoate-lufenuron (EB-LFR) and the low-toxicity ecdysone agonist RH-5849. EB-LFR was associated with observed reductions in core gut symbionts (Gilliamella, Snodgrassella, Lactobacillus), a transient increase in Bifidobacterium, and the detection of opportunistic taxa such as Serratia marcescens and Enterobacter hormaechei. In contrast, RH-5849 was associated with broad reductions in beneficial bacteria without detectable pathogen emergence, suggesting a more moderate alteration of microbiota composition. Because microbiota analyses were based on single pooled samples per treatment, these results represent exploratory, qualitative insights into early microbial responses. Together with acute toxicity data, the findings suggest that insecticides with contrasting toxicity classes may differentially affect gut microbiota composition in honey bees and highlight the value of incorporating gut microbiota endpoints into pesticide risk-assessment frameworks to better anticipate sublethal effects on pollinator health. Full article

The western honey bee (Apis mellifera) represents a key pollinator for both crops and wild plants, and its global decline raises serious concerns for ecosystem stability and agricultural productivity. Several biotic and abiotic factors are responsible for colony losses, including alterations in the bee microbiota, which is essential for host metabolism, development, and immune responses. In this study, we employed both molecular protocols and metagenomic approaches based on Next-Generation Sequencing (NGS) to characterize the microbial composition and identify commensal, symbiotic, and pathogenic microorganisms, both known and emerging, associated with A. mellifera colonies from 20 apiaries across the Italian territory. Molecular screening revealed Vairimorpha ceranae, Lotmaria passim, Crithidia mellificae and several viruses, including Sacbrood virus (SBV), Black Queen Cell virus (BQCV), Deformed Wing virus (DWV), Chronic Bee Paralysis virus (CBPV) and Acute Bee Paralysis virus (ABPV). 16S rRNA gene sequencing highlighted a bacterial community mainly composed of the Lactobacillus, Gilliamella, and Snodgrassella genera. Virome analysis detected members belonging to the families Dicistroviridae and Iflaviridae, as well as previously unreported viruses in Italy, such as Apis rhabdovirus (ARV-1, ARV-2), Bee Macula-like virus (BeeMLV), and Lake Sinai virus (LSV). This research expands current knowledge of the A. mellifera metagenome, offering valuable insights for epidemiological surveillance and diagnostic assay development. Full article

Climate change is intensifying winters in temperate regions, posing a serious threat to Apis mellifera health. The gut microbiome, a distinct community of core bacterial species, is central to overwintering success by supporting immune function, nutrient assimilation, and pathogen resistance, but is highly sensitive to environmental stressors such as cold temperatures and dietary shifts. Stress-induced perturbations can reshape the composition and relative abundance of the gut microbiome in honey bees, leading to adverse effects on host health, physiological functions, and overwinter survival. Cold temperatures and additional stressors further destabilize the microbiome, compounding these effects. This review is the first to synthesize current knowledge on how extrinsic factors, such as diet, antibiotics, and pathogens, and intrinsic factors, including age and strain, influence the composition and function of the honey bee gut microbiota during the overwintering period. Given the increasing severity of winter conditions under climate change, a deeper understanding of microbiome–host–environment interactions is essential for improving honey bee resilience. By integrating evidence on the microbiome’s roles in nutrient utilization, immune modulation, and pathogen defense, this review outlines a framework to guide future research aimed at sustaining pollinator health and nutrition in a changing global climate. Full article

This study evaluated Apis mellifera brood fat extracts as a sustainable alternative to beeswax for anti-inflammatory topical delivery, including their formulation into nanostructured lipid carriers (NLCs). Brood fat was extracted using acetone, ethyl acetate (EA), and hexane, and the resulting extracts were characterized for fatty acid composition and physicochemical properties. Safety was assessed using the hen’s egg chorioallantoic membrane test and cytotoxicity testing in RAW 264.7 macrophages. Anti-inflammatory activity was assessed by inhibition of lipopolysaccharide-induced interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) production. The most suitable extract was formulated into NLCs using sugar squalane as liquid lipid, and the effects of lipid ratio and preparation method were investigated. The results showed that the ethyl acetate extract had the highest yield. Compared with beeswax, all fat extracts exhibited a favorable oleic acid–rich fatty acid profile with comparable crystallinity and thermal behavior, while showing significantly enhanced anti-inflammatory activity (p < 0.05). All extracts and their NLCs were non-irritating and non-cytotoxic. Ethyl acetate extract-based NLCs exhibited favorable particle sizes (72.1 ± 0.3 nm) and narrow polydispersity (0.14 ± 0.00), with high-pressure homogenization producing smaller particles compared to probe sonication without affecting IL-6 or TNF-α inhibition. Therefore, A. mellifera brood fat extract is a sustainable anti-inflammatory lipid source with strong potential as an alternative to beeswax in topical nano-formulations. Full article

Honey bees (Apis mellifera L.) are considered highly significant economic insects. It is a source of valuable food and medicinal products such as honey, bee pollen, royal jelly, bee brood, and beeswax, which possess excellent nutritional and pharmacological properties. Nevertheless, honey bee health and productivity were often challenged by various environmental factors. Therefore, bee colony management is of the utmost importance. In this light, bee supplements and gut microbiota are crucial to ensure that bees receive sufficient nutritional value to maintain their health and productivity. In this study, we isolate and characterize lactic acid bacteria from the hindgut of the worker bee. 16S rRNA sequencing revealed that three isolated bacteria were Apilactobacillus kunkeei (AK), Lactiplantibacillus sp. (LP), and Lactobacillus brevis (LB). Three species of lactic acid bacteria were investigated for potential probiotic properties by supplementing 50% (w/w) sucrose syrup in the form of a direct-fed microorganism (DFM). The supplement with DFM had no negative effect on average lifespan. Examination took place of the impact of probiotics on the development of the hypopharyngeal glands (HPGs) in the bee’s head at days 3, 6, and 9 post-treatments. The cage-bees fed by pollen and DFM syrup exhibited acini surface areas ranging from 0.020 to 0.023 mm². The L. brevis (LB) group exhibited enhanced HPG development, with an average acini size of 0.027 ± 0.007 mm² at day 6, while the non-treatment control had an average acini size of 0.023 ± 0.006 mm². The significant size differences were maintained throughout the 9-day period. In addition, the DFM syrup enhanced microbial protein content in the bee head, digestibility, and community complexity compared with the negative control groups. Therefore, the DFM syrup with a potential strain of probiotic may enhance overall honey bee health status. Full article

Behavioral maturation is essential for the proper functioning of honey bee societies and is regulated by multiple factors such as juvenile hormone (JH) and nutritional deficiency. Although recent studies have shown that surface-associated microbiota in insects can modulate host behavior, the relationship between body surface microbiota and behavioral maturation in honey bees remains largely unexplored. This study aimed to determine whether the surface microbial communities of honey bees shift with behavioral maturation. By using 16S rRNA gene amplicon sequencing, we analyzed the surface microbiota of worker bees at different behavioral stages (newly emerged bees, nurses, and foragers) in both Eastern honey bee Apis cerana and Western honey bee Apis mellifera. The results showed that in both honey bee species, nurse bees exhibited the lowest microbial diversity, while forager bees showed the highest, and newly emerged bees had an intermediate level of microbial diversity. Moreover, beta diversity analyses revealed that the body surface microbiota of worker bees significantly varied across behavioral stages in both bee species and differed between the two bee species at the same behavioral stage. Additionally, in both bee species, at the phylum level, Pseudomonadota, Bacillota, and Actinobacteriota dominated the worker bee body surface microbiota; at the genus level, foragers had more Gilliamella, while nurses harbored more Lactobacillus. Together, our findings reveal the emergence of distinct microbial signatures on honey bee body surfaces during behavioral maturation. Full article

This study provides an updated overview of Anthophila (wild bees and honey bees) diversity and conservation status in Algeria, explicitly distinguishing between the managed honey bee (Apis mellifera) and native wild Anthophila species. Using a systematic PRISMA-based literature analysis, more than 179 bee species have been documented across Mediterranean and semi-arid ecosystems, confirming their irreplaceable contribution to ecosystem resilience and crop pollination and beekeeping systems. The majority of Algeria’s Anthophila diversity is represented by endemic and native wild bees that sustain natural ecosystems. However, they are under growing human-caused (anthropogenic) pressures in the Anthropocene, including pressure from habitat loss and fragmentation, agricultural intensification, widespread pesticide use, and climate change. In addition, pathogenic threats such as Varroa destructor, Nosema, and associated viruses are well documented in honey bees, while evidence for their presence and impact in wild bees in Algeria remains very limited. These stressors not only weaken specialist species but also accelerate biotic homogenization dominated by A. mellifera. Recent genomic research on native honey bee populations has revealed adaptive signatures linked to immunity and social behavior, offering new opportunities for innovative conservation strategies based on molecular and genetic tools. Such insights highlight the value of preserving local strains, which may hold key traits for resilience under changing environmental conditions. To safeguard Anthophila biodiversity, this study underscores the urgent need for Algeria to implement proven conservation strategies, including habitat restoration initiatives and Anthophila-friendly farming approaches, which are common internationally but remain largely unaddressed at the national scale. By integrating cutting-edge genetic research, ecological restoration, and sustainable innovation, Algeria, with its diverse habitats and largely unexplored Anthophila fauna, holds considerable potential for advancing biodiversity conservation strategies that also support food security. However, this potential can only be realized through further in-depth research and comprehensive species inventories. Full article

Pollen acts as both a gametophyte for plant reproduction and a vital nutrient source for bees. Adult honey bees (Apis mellifera) mix pollen with nectar, enzymes, and microbes to create ‘bee bread’, diverting pollen from plant reproduction and re-appropriating it as larval food. However, the point at which corbicular pollen becomes nonviable is largely unknown. This question is important not only because it explicitly addresses pollen viability while bees pollinate, but also because it informs the food vs. fertilization tradeoff at the center of bee–angiosperm mutualisms. Here, we investigated changes in pollen viability during foraging bouts of honey bees. We observed pollen germination across two plant species: Allium tuberosum and Solidago rigida. Bee-collected pollen was contrasted against fresh pollen directly from floral anthers, de-ionized water-soaked pollen, and sucrose solution-washed pollen (a nectar substitute). The bee-collected pollen exhibited significant reductions in germination for both A. tuberosum and S. rigida pollen, compared to controls and the sucrose solution. Pollen viability, therefore, was greatly reduced while the bees in our study were foraging, suggesting that honey bees render pollen nonviable as they pollinate. These findings reveal why corbicular pollen contributes little to plant fertilization, highlighting the importance of non-corbicular ‘body pollen’. Full article

Beekeeping is a widespread economic activity in rural Tanzania, supporting over 2 million livelihoods. The country’s forests and woodlands, covering approximately 55% of its land area, provide habitat for an estimated 9.2 million honeybee colonies. This positions Tanzania as the second-largest honey producer in Africa and tenth globally. Absence of current information and effective policies hinders exploitation of the industry’s potential. This review presents scientific insights into Tanzania’s beekeeping sector, focusing on honeybee species, bee products, management practices, and conservation. Among three documented subspecies of Apis mellifera (Linnaeus, 1758), A. m. scutellata is the most widespread and commonly managed by indigenous beekeepers. Tanzania annually produces over 31,000 tonnes of honey and 1800 tonnes of beeswax, generating approximately USD 77.5 million and contributing about 1% to national GDP. The industry supports livelihoods, food security, and biodiversity conservation. Its sustained growth requires effective legal and administrative support, expanded scientific research, enhanced innovation, coordinated partnerships, and integrated nationwide initiatives. Full article

Many biomedical applications require a detailed understanding of the action of antimicrobial peptides on biological membranes. The cationic hemolytic peptide melittin, a major component of European honey bee (Apis mellifera) venom, is considered a model for elucidating lipid–protein interactions that are important for the function of biological systems. Here, we address the surface properties of human erythrocytes and rat liver mitochondrial membranes under in vitro melittin treatment. These membranes are negatively charged at neutral pH and represent primary targets of melittin’s effects in the onset of inflammatory diseases. The correlation between the functional activity of membrane systems and their surface electrical charge was assessed using microelectrophoresis, hemolysis assays, membrane transport measurements, lipid peroxidation analysis, and fluorescence microscopy. A mechanistic hypothesis for the divergent effects of sub-lytic, pre-pore doses of melittin on erythrocytes and mitochondria is discussed. At low concentrations, melittin interacts electrostatically with erythrocyte membranes, resulting in altered proton transport through the Band 3 protein. Melittin also induces changes in erythrocyte morphology and malondialdehyde content, as well as aggregation of mitochondrial vesicles. The electrokinetic mechanism of melittin action, associated with membrane stability, provides a novel perspective on its potential relevance to biomedical applications. Full article

The conservation and breeding of the western honey bee (Apis mellifera) is central dependent on accurate subspecies assignment, but the most commonly used methods are labor-intensive classical morphometrics and costly molecular assays. We developed an XGBoost-based classification framework using a compact set of routinely measurable characters. A curated dataset of labeled workers was measured under harmonized protocols; features were screened according to embedded importance, and model performance was assessed using five-fold cross-validation, outperforming standard machine learning baselines. The resulting model using only the top 10 characters—primarily forewing venation angles and abdominal plate metrics—achieved high performance (accuracy = 0.98; F1 = 0.99) and an area under the receiver operating characteristic curve (AUC) of 0.99 (95% CI = 0.995–0.999). SHAP analyses confirmed the discriminatory contributions of these features, while error inspection suggested that misclassifications were concentrated in morphologically overlapping lineages. The model’s performance supports its use as a rapid triage tool alongside genetic testing, providing a scalable and interpretable tool for researchers to create and deploy custom morphometric models, demonstrated here for A. mellifera but portable to other insect taxa. Full article