Changes in chemical composition and antioxidant activity of royal jelly produced at different floral periods during migratory beekeeping

S-methyl-L-cysteine sulfoxide as a characteristic marker for rape royal jelly: Insights from untargeted and targeted metabolomic analysis

Among the varieties of royal jelly (RJ), often referred to as "liquid gold", rape royal jelly (RRJ) is popular because of its superior nutritional value. However, existing physicochemical indicators fall short in identifying different types of RJ. Utilizing a UPLC-Q-Exactive Orbitrap-MS technique combined with metabolomics, this study was the first to identify S-methyl-L-cysteine sulfoxide (SMCSO) in RRJ, thereby it from other types of RJ. Subsequent to this observation, a method based on UPLC-QqQ-MS/MS, was developed and optimized for precise SMCSO quantification in RRJ, achieving a detection range of 77.55-112.68 mg/kg. Furthermore, an analysis of honey and bee bread harvested from the same batch of rape plants confirmed the presence of SMCSO, with the highest concentration detected in rape bee bread. In light of these findings, SMCSO emerges as a potent authenticity marker for RRJ.

Exploring the in vitro potential of royal jelly against glioblastoma and neuroblastoma: impact on cell proliferation, apoptosis, cell cycle, and the biomolecular content

Neuroblastoma and glioblastoma are the most commonly seen nervous system tumors, and their treatment is challenging. Relatively safe and easy acquisition of nutraceutical natural products make them suitable candidates for anticancer research. Royal jelly (RJ), a superfood, has many biological and pharmacological activities. This study was conducted to, for the first time, elucidate its anticancer efficiency, even in high doses, on neuroblastoma and glioblastoma cell lines through cell viability, apoptosis, cell cycle and biomolecular content evaluation. We performed experiments with RJ concentrations in the range of 1.25-10 mg mL-1 for 48 h. Cell viability assays revealed a notable cytotoxic effect of RJ in a concentration-dependent manner. Treatment with a high dose of RJ significantly increased the apoptotic cell population of both cell lines. Furthermore, we observed G0-G1 phase arrest in neuroblastoma cells but G2-M arrest in glioblastoma cells. All these cellular changes are closely associated with the alterations of the macromolecular makeup of the cells, such as decreased saturated lipid, protein, DNA and RNA amounts, protein conformational changes, decreased protein phosphorylation and increased protein carbonylation. These cellular changes are associated with RJ triggered-ROS formation. The clear segregation between the control and the RJ-treated groups proved these changes, obtained from the unsupervised and supervised chemometric analysis. RJ has good anticancer activity against nervous system cancers and could be safely used with current treatment strategies.

A review of fermented bee products: Sources, nutritional values, and health benefits

Bee products have garnered considerable interest due to their abundant nutritional content and versatile biological activities. The utilization of bee products as fermentation materials has shown favorable potential for increasing nutrients, altering texture, and endorsing unique tastes. This review critically examines the existing literature on fermented bee products, with a specific emphasis on the impact of fermentation on their nutritional composition and potential health benefits. The raw materials, strains, conditions, and methodologies employed in the fermentation of bee products, as well as the utilization of bee products as fermentation raw materials/excipients, are reviewed. We also present a special focus on the nutritional composition and content of bioactive substances, such as polyphenols and volatile organic compounds, in fermented bee products. Additionally, the influence of fermentation on bee product ingredients and their health benefits is summarized. Fermented bee products substantially benefit human health, with superior antioxidant, anti-inflammatory, and anti-allergic properties compared to non-fermented bee products. Finally, this article discusses the types, strains, health benefits, production processes, and market prospects of fermented bee products, which are expected to become an important part of human food culture as functional food or nutritional supplements. The aforementioned findings highlight the remarkable nutritional value and bioactive properties exhibited by fermented bee products.

Effects of different floral periods and environmental factors on royal jelly identification by stable isotopes and machine learning analyses during non-migratory beekeeping

It is crucial to monitor the authenticity of royal jelly (RJ) because the qualities of RJs produced by different floral periods vary substantially. In the context of non-migratory beekeeping, this study aims to identify rape RJ (RRJ), chaste RJ (CRJ), and sesame RJ (SRJ) based on δ13C, δ15N, δ2H, and δ18O combined with machine learning and to evaluate environmental effect factors. The results showed that δ13C (-27.62‰ ± 0.24‰), δ15N (2.88‰ ± 0.85‰), and δ18O (28.02‰ ± 1.30‰) of RRJ were significantly different from other RJs. The δ13C, δ2H, and δ18O in CRJ and SRJ were strongly correlated with temperature and precipitation, suggesting that these isotopes are influenced by environmental elements such as sunlight and rainfall. In addition, the artificial neural network (ANN) model was superior to the random forest (RF) model in terms of accuracy, sensitivity, and specificity. This study revealed that combining stable isotopes with ANN models and the unique correlation between stable isotopes and environmental factors could provide promising ideas for monitoring the authenticity of RJ.

Effects of Sucrose Feeding on the Quality of Royal Jelly Produced by Honeybee Apis mellifera L

Royal jelly (RJ) is a highly nutritious secretion of the honeybees' hypopharyngeal glands (HPGs). During RJ production, colonies are occasionally subjected to manual interventions, such as sucrose feeding for energy supplementation. This study aimed to assess the impact of sucrose feeding on the composition of RJ. The results indicated that RJ obtained from sucrose-fed colonies exhibited significantly higher levels of fructose, alanine, glycine, tyrosine, valine, and isoleucine compared to the honey-fed group. However, no significant differences were observed in terms of moisture content, crude protein, 10-HDA, glucose, sucrose, minerals, or other amino acids within the RJ samples. Moreover, sucrose feeding did not have a significant effect on midgut sucrase activity, HPGs development, or the expression levels of MRJP1 and MRJP3 in nurse bees. Unsealed stored food samples from sucrose-fed bee colonies demonstrated significantly higher sucrose levels compared to sealed combs and natural honey. Additionally, natural honey exhibited higher moisture and Ca levels, as well as lower levels of Zn and Cu, in comparison to honey collected from bee colonies fed sucrose solutions. Based on these findings, we conclude that sucrose feeding has only a minor impact on the major components of RJ.

The Composition of Fatty Acids in Bee Pollen, Royal Jelly, Buckthorn Oil and Their Mixtures with Pollen Preserved for Storage

Honey produced by A. mellifera contains minor components present in the nectar collected from plants. Various studies of honey components and all other bee products can be informative in assessing their quality. The aim of the present study was to determine the content and composition of fatty acids (FAs) in sea buckthorn oil (SBO), royal jelly (RJ) and bee pollen (BP) and the changes in FAs content in these products during storage. The diversity of FAs and the effect of storage time on FAs content was also evaluated for the prepared-for-preservation mixtures, which included the following samples: pollen mixed with honey at a ratio of 1:2 (w/w); sample BPH, a well; BPH + 1% (w/w) SBO; and BPH + 1% (w/w) SBO + 2% (w/w) RJ. Fresh bee-collected pollen and RJ were stored at -20 °C, whereas the conserved samples were stored at +4 °C in hermetically sealed jars. The data revealed that RJ demonstrated the highest diversity of fatty acids compared to BP and BP prepared for storage with honey along with SBO and RJ. Palmitic and stearic acids were found in the highest amounts out of the eight saturated fatty acids identified in the studied SBO and RJ. The amount of these fatty acids in RJ compared to SBO was 1.27 and 6.14 times higher, respectively. In total, twenty-two unsaturated fatty acids (USFA) were identified in RJ and fourteen were found in SBO. The SBO used in this study was found to be high in linoleic acid, resulting in an increased n-6 fatty acids ratio in the prepared samples. Essential fatty acids eicosapentaenoic (EPA) and docosahexaenoic (DHA) were found in RJ, as well as in BP and BP mixed with honey. These FAs were not identified in the samples prepared with SBO even in the sample supplemented with RJ. The highest decrease in docosadienoic fatty acid was found in the BPH sample compared to BP, while arachidonic acid mostly decreased in BPH + 1% SBO compared to the BPH + 1% (w/w) SBO + 2% (w/w) RJ samples stored at +4 °C. Bee-collected pollen had the greatest influence on the number of FAs in its mixture with honey.

Metabolomics Reveals Distinctive Metabolic Profiles and Marker Compounds of Camellia (Camellia sinensis L.) Bee Pollen

Camellia bee pollen (CBP) is a major kind of bee product which is collected by honeybees from tea tree (Camellia sinensis L.) flowers and agglutinated into pellets via oral secretion. Due to its special healthcare value, the authenticity of its botanical origin is of great interest. This study aimed at distinguishing CBP from other bee pollen, including rose, apricot, lotus, rape, and wuweizi bee pollen, based on a non-targeted metabolomics approach using ultra-high performance liquid chromatography-mass spectrometry. Among the bee pollen groups, 54 differential compounds were identified, including flavonol glycosides and flavone glycosides, catechins, amino acids, and organic acids. A clear separation between CBP and all other samples was observed in the score plots of the principal component analysis, indicating distinctive metabolic profiles of CBP. Notably, L-theanine (864.83-2204.26 mg/kg) and epicatechin gallate (94.08-401.82 mg/kg) were identified exclusively in all CBP and were proposed as marker compounds of CBP. Our study unravels the distinctive metabolic profiles of CBP and provides specific and quantified metabolite indicators for the assessment of authentic CBP.

Targeted and Suspect Fatty Acid Profiling of Royal Jelly by Liquid Chromatography—High Resolution Mass Spectrometry

Royal jelly (RJ) is a bee product produced by the mandibular and hypopharyngeal glands of worker honeybees which has attracted special attention because of its numerous pharmacological activities and its applications to dermatology and cosmetics. In 2020, we demonstrated a liquid chromatography–high resolution mass spectrometry (LC–HRMS) method for the determination of seven medium-chain FFAs in RJ samples. The aim of the present work was to extend our studies on FA profiling of RJ, exploring the presence of common long-chain saturated, mono-unsaturated and poly-unsaturated free FAs in RJ samples using this LC–HRMS method. Among twenty common FAs studied by a targeted approach, palmitic acid, stearic acid and oleic acid were found at concentrations higher than the rest of the FAs (the concentrations of these three acids ranged from 37.4 to 48.0, from 17.7 to 24.0 and from 9.4 to 11.1 mg/100 g of fresh RJ, respectively). The high mass accuracy of LC–HRMS allowed the application of a suspect approach, which enabled the exploration of various C9 and C11 FAs, as well as hydroxylated C12 FAs. Nonenoic acid was indicated as the most abundant among these acids. In addition, for the first time, the presence of a variety of regio-isomers of hydroxymyristic, hydroxypalmitic and hydroxystearic acids was demonstrated in RJ samples.

Effects of Major Royal Jelly Proteins on the Immune Response and Gut Microbiota Composition in Cyclophosphamide-Treated Mice

Increasing evidence suggests that royal jelly (RJ) has exceptional biological properties, and that major royal jelly proteins (MRJPs) are the key active factors in RJ. The objective of this study was to compare the difference in the protein content between RJ and MRJPs using non-labeled, quantitative proteomics technology, and to investigate the adjustment features and mechanisms of MRJPs on murine immune functions and the composition of intestinal flora in cyclophosphamide-treated mice. Results showed that, during the process of extracting MRJPs, the ratio of the protein types in the main protein and other proteins decreased significantly, except for MRJP1 and MRJP7, which demonstrated that an enriching effect of MRJP1 and MRJP7 was present during the extraction process. Cyclophosphamide-induced mice were orally administered MRJPs. Results showed that the middle-dose group, which received 0.25 g/(kg·bw) of royal jelly main protein, demonstrated a clear impact on the development of the spleen and liver, the quantity of peripheral blood leukocytes, immunoglobulin content, immune factor level, and the proliferation ability of spleen lymphocytes. A 16S rRNA high-throughput sequencing technology analysis showed that MRJPs could improve the component and richness of intestinal flora and raise the immunity of mice. The above-mentioned results indicated that the application of MRJPs is very likely to have an advantage effect on murine immune functions.

Effect of queen cell numbers on royal jelly production and quality

Royal jelly (RJ) is a popular functional food with a wealth of health-promoting effects. Over 90% of the global RJ is produced in China mainly by a high RJ-producing honeybee (RJB) strain that can accept and feed a great number of queen larvae for RJ production. To elucidate RJ changes due to queen cell numbers (QCNs), we compared the yield, larval acceptance rate, metabolic and proteomic profiles, and antioxidant activities of RJ from 1 to 5 strips of queen cells (64 per strip) in RJB colonies. As QCNs increased, the larval acceptance rate was not found to vary (p = 0.269) whereas the RJ weight per cell began to significantly decline in the 5-strip colonies (p < 0.05). Increased QCNs had a profound impact on RJ metabolic profiles and mainly reduced fatty acid levels. Remarkably, the 10-hydroxy-2-decenoic acid (10-HDA) content, a most important indicator of RJ quality, declined gradually from 2.01% in the 1-strip colonies to 1.52% in the 5-strip colonies (p < 0.001). RJ proteomic profiles were minimally altered and antioxidant activities were not significantly changed by QCNs. Collectively, the metabolomics and proteomics data and the antioxidant activity test represent a global evaluation of the quality of RJ produced with different QCNs. Our findings gain new insights into higher-quality RJ production using the high-yielding RJBs.