Royal jelly is a substance secreted by the hypopharyngeal and mandibular glands of nurse honey bees, serving as crucial nutritional source for young larvae, queen honey bees, and also valuable product for humans. In this study, the effect of the feed supplements on the nutritional composition and qualities of royal jelly was investigated. Two types of royal jelly samples were acquired: one from honey bees fed with sugar syrup as a feed supplement and the other from honey bees fed with honey. The production, harvesting, and storage of all royal jelly samples followed standard procedures. Parameters for quality assessment and nutritional value, including stable carbon isotopic ratio, moisture content, 10-hydroxy-2-decenoic acid (10-HDA) level, carbohydrate composition, amino acid composition, and mineral contents, were analyzed. The results revealed that despite variability in moisture content and carbohydrate composition, fructose was lower (2.6 and 4.1 g/100 g as is for sugar-fed and honey-fed royal jelly, respectively) and sucrose was higher (7.5 and 2.7 g/100 g as is for sugar-fed and honey-fed royal jelly, respectively) in the sugar-fed group. The stable isotope ratio (−16.4608‰ for sugar-fed and −21.9304‰ for honey-fed royal jelly) clearly distinguished the two groups. 10-HDA, amino acid composition, and total protein levels were not significantly different. Certain minerals, such as potassium, iron, magnesium, manganese, and phosphorus were higher in the honey-fed group. Hierarchical analysis based on moisture, sugar composition, 10-HDA, and stable carbon isotopes categorized the samples into two distinct groups. This study demonstrated that the feed source could affect the nutritional quality of royal jelly.

Honey bees (Apis mellifera) are major pollinators, playing a critical role in global food production, biodiversity, and ecosystem stability. However, their populations are increasingly threatened by multiple interacting stressors, including pesticide exposure. Among these, agricultural insecticides and anti-Varroa acaricides such as dinotefuran and amitraz can persist in hive matrices, resulting in chronic and combined exposure. This study investigates the low lethal (LC₁₀ and LC₃₀) effects of these compounds, individually and in combination, on honey bee survival, immune function, oxidative stress responses, detoxification pathways, and hypopharyngeal gland morphology. Both pesticides negatively affected honey bee health at low lethal concentrations, with dinotefuran showing higher toxicity. Exposure led to the reduced survival, suppression of vitellogenin expression, and dysregulation of genes related to antioxidant defense, immunity, and detoxification. Additionally, high concentrations of dinotefuran and its combination with amitraz impaired hypopharyngeal gland morphology. Notably, co-exposure resulted in synergistic toxic effects, exacerbating physiological damage beyond individual treatments. These findings emphasize the potential risks of combined exposure to agricultural and beekeeping pesticides. A more comprehensive risk assessment and stricter regulations are urgently needed.

Monofloral honeys are widely recognized for their distinct chemical characteristics which are largely influenced by botanical origin. This study aimed to compare the physicochemical and functional properties of monofloral honeys produced in South Korea. Five monofloral honey types, Castanea crenata, Robinia pseudoacacia, Toxicodendron spp., Hovenia dulcis, and Styrax japonicus, were analyzed, and their floral origins were confirmed through melissopalynological analysis. Physicochemical parameters (moisture content, total soluble solids, hydroxymethylfurfural content, stable carbon isotope ratio, free acidity, pH, color, and sugar composition), along with amino acid profiles, predicted glycemic index (GI), and antioxidant activity, were determined. Most physicochemical parameters showed statistically significant differences among honey types. Amino acid composition differed markedly among honey types, with Castanea honey exhibiting higher levels of proline, phenylalanine, and leucine compared to Robinia and Styrax honeys. Predicted GI values were predominantly within the low-GI range, with no statistically significant differences observed among floral origins. Antioxidant activity showed a similar trend to amino acid content, with Castanea honey displaying the highest antioxidant values. These findings demonstrate that botanical origin is a key determinant of the physicochemical and in vitro functional attributes of honey, including antioxidant activity and predicted GI, and provide a scientific basis for the characterization of South Korean monofloral honeys.

Pollen limitation compromises honey bee health and pollination services, and existing pollen substitutes are typically formulated around crude protein content while lacking the long-chain omega-3 fatty acids naturally present in pollen and bee-collected re-sources. To address both protein and fatty acid gaps in current substitutes, this study evaluated marine-protein and insect-larvae-based diets. We assessed how formulations using Asian seabass (Lates calcarifer) and insect larvae affect the nutrition, physiology, longevity, and gut microbiota of Apis mellifera L. Newly emerged bees were fed for 35 days on: sugar syrup (negative control), sugar syrup and natural pollen (positive control), or four experimental diets: seabass-based (SB), or SB supplemented with meal-worm (SBM), or wax moth (SBW), or black soldier fly (SBB). Experimental diets (12.48–15.59% crude protein, vs. 17.24% in natural pollen) while SB supplied eicosapentaenoic acid (39.3–53.3 mg/100 g) and docosahexaenoic acid (37.2–52.3 mg/100 g), and SBB was additionally rich in lauric acid (604.3 mg/100 g). SBB- and SBM-fed bees exhibited the greatest hypopharyngeal gland development (0.123 mm and 0.115 mm, respectively, vs. 0.060 mm in sugar-only controls), with no significant difference from SB alone. All SB-based diets supported significantly greater survival than the sugar-only control (log-rank p < 0.0001) and did not differ significantly from the natural pollen treatment with SBB showing the highest and most consistent day-35 survival (81.1%). All sea-bass-based diets significantly altered the gut microbial community structure, promoting short-chain fatty acid (SCFA)-associated bacteria such as Faecalibacterium prausnitzii and Blautia wexlerae. This enrichment may reflect not only the omega-3 and lauric acid content of the diets but also the presence of substrates that can be utilized by gut microbes, which may exert prebiotic-like effects by favoring SCFA-producing bacteria. These results demonstrate that marine and insect-derived nutrients can supply protein while also providing beneficial lipids and microbially utilizable substrates that promote the enrichment of beneficial SCFA-associated bacteria not typically dominant in the honey bee gut. These enriched diets, particularly SBB, are promising candidates war-ranting further evaluation at the colony and field levels.

The rhinoceros beetle (Xylotrupes gideon) requires safe and nutritious flake soil substrate for commercial rearing in northern Thailand, yet optimal lignocellulosic formulations remain undefined. This study evaluated five flake soil formulations substituting lignin-rich cadamba sawdust (0–100%) with cellulose-rich corn stover, plus cattle manure and rice bran, fermented for 90 days. Fermentation engineered the cellulose-lignin-hemicellulose matrix, reducing lignin from 25.07% to 7.30% while enriching cellulose from 29.73% to 33.83% and hemicellulose from 6.67% to 17.42%. Increasing corn stover enhanced crude protein (5.46–7.53%) and nitrogen-free extract (24.17–34.14%), creating T1 (25% substitution) as the optimal cellulose-based composite for X. gideon rearing. Microbial analysis showed T1-T2 supported highest α-diversity and lactic acid bacteria enrichment, suppressing pathogens like Escherichia coli and Salmonella enterica. Fermentation degraded >99% glyphosate residues (from 106 mg/kg to <0.25 mg/kg or undetectable). T1 is recommended as the optimal, sustainable flake soil for X. gideon rearing, balancing nutrition, microbiology, and safety while valorizing agricultural wastes.