Royal jelly from different floral sources possesses distinct wound-healing mechanisms and ingredient profiles

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.

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.

Integrated microbiomic and metabolomic analyses reveal the mechanisms by which bee pollen and royal jelly lipid extracts ameliorate colitis in mice

Bee pollen (BP) and royal jelly (RJ) have shown therapeutic effects against colitis, but the functional components contained therein remain elusive. Here, we used an integrated microbiomic-metabolomic strategy to clarify the mechanism by which bee pollen lipid extracts (BPL) and royal jelly lipid extracts (RJL) ameliorated dextran sulfate sodium (DSS)-induced colitis in mice. Lipidomic results showed that levels of ceramide (Cer), lysophosphatidylcholine (LPC), phosphatidylcholine (PC), and phosphatidylethanolamine (PE) were significantly higher in BPL than in RJL. The anti-inflammatory efficacy of BPL surpassed that of RJL, although both BPL and RJL could attenuate DSS-induced colitis through several mechanisms: reducing the disease activity index (DAI); decreasing histopathological damage; inhibiting the expression of genes encoding proinflammatory cytokines; improving intestinal microbial community structure, and modulating host metabolism. These findings demonstrated that BPL and RJL have great potential as functional ingredients for the production of dietary supplements to prevent early colitis.

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.

Enhancement of the Antioxidant Capacity of Thyme and Chestnut Honey by Addition of Bee Products

Honey consumption and imports have increased in recent years, and it is considered by consumers to be a healthy alternative to more commonly used sweeteners. Honey contains a mixture of polyphenols and antioxidant compounds, and the botanical origin and geographical area of collection play an important role on its chemical composition. The present study investigated the physicochemical properties, total phenolic content and antioxidant capacity of Spanish thyme honey and chestnut honey, and their mixtures with royal jelly (2% and 10%) and propolis (2% and 10%). The analysis of the physicochemical parameters of both honey samples showed values within the established limits. Propolis showed the highest value of total phenolic content (17.21–266.83 mg GAE/100 g) and antioxidant capacity (DPPH, ORAC and ABTS assays; 0.63–24.10 µg eq. Tx/g, 1.61–40.82 µg eq. Tx/g and 1.89–68.54 µg eq. Tx/g, respectively), and significantly reduced ROS production in human hepatoma cells. In addition, mixtures of honey with 10% of propolis improved the results obtained with natural honey, increasing the value of total phenolic content and antioxidant capacity. A significant positive correlation was observed between total phenolic compounds and antioxidant capacity. Therefore, the antioxidant capacity could be attributed to the phenolic compounds present in the samples, at least partially. In conclusion, our results indicated that thyme and chestnut honey supplemented with propolis can be an excellent natural source of antioxidants and could be incorporated as a potential food ingredient with biological properties of technological interest, added as a preservative. Moreover, these mixtures could be used as natural sweeteners enriched in antioxidants and other bioactive compounds.

The in vitro and in vivo antibacterial activities of uniflorous honey from a medicinal plant, Scrophularia ningpoensis Hemsl., and characterization of its chemical profile with UPLC-MS/MS

ETHNOPHARMACOLOGICAL RELEVANCE

According to the Compendium of Materia Medica, honey has been used as a traditional medicine in treatment against mucositis, tinea, hemorrhoids and psoriasis. In complementary medicine, due to its significant antimicrobial activity, honey has been widely used as a remedy for skin wounds and gastrohelcosis for thousands of years.

AIM OF THE STUDY

This study is aimed at exploring the antimicrobial activity and mechanisms of honey sourced from medicinal plants, and revealing the composition-activity relationship, to facilitate their complementary and alternative application in the therapy of bacterial infectious diseases.

MATERIALS AND METHODS

Eight kinds of medicinal plant-derived uniflorous honey, native to China, were gathered. Their antimicrobial activities were evaluated in vitro, and then in vivo with the systemically infected mouse model and the acute skin infection model. SYTOX uptake assay, scanning electron microscopy, DNA binding assay, and quantitative real-time PCR, were carried out to elucidate the antibacterial mechanisms. This was followed by an investigation of the componential profile with the UPLC-MS/MS technique.

RESULTS

It was found that Scrophularia ningpoensis Hemsl. (figwort) honey (S. ningpoensis honey) exhibited broad-spectrum and the strongest antibacterial potency (MICs of 7.81-125.00%, w/v), comparable to manuka honey. In the in vivo assays, S. ningpoensis honey significantly decreased the bacterial load of the muscles under the acute MRSA-infected skin wounds; the sera level of TNF-α in the S. aureus and P. aeruginosa-infected mice decreased by 45.38% and 51.75%, respectively, after the treatment of S. ningpoensis honey (125 mg/10 g). It was capable of killing bacteria through disrupting the cell membranes and the genomic DNA, as well as down-regulating the expression of genes associated with virulence, biofilm formation and invasion, including icaA, icaD, eno, sarA, agrA, sigB, fib and ebps in S. aureus, and lasI, lasR, rhlI, rhlR and algC in P. aeruginosa. Apart from H₂O₂, some other nonperoxide compounds such as adenosine, chavicol, 4-methylcatechol, trehalose, palmitoleic acid and salidroside, might play a vital role in the antibacterial properties of S. ningpoensis honey.

CONCLUSIONS

This is the first study to thoroughly investigate the antibacterial activity, mode of action, and componential profile of S. ningpoensis honey. It suggested that S. ningpoensis honey might be a potential supplement or substitute for manuka honey, for the prevention or treatment of bacterial infections. It will facilitate the precise application of medicinal plant-sourced honey, provide a new thread for the development of antibacterial drugs, and assist in the distinction of different kinds of honey.

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

Over 90% of global royal jelly (RJ), a functional food with various health benefits, is produced in China mainly by migratory beekeeping of a high RJ-producing honeybee (RJB) strain. To explore quality changes of RJ produced by migratory RJBs at different floral periods, we performed metabolomics and proteomics analysis and assessed RJ antioxidant activity. Overall, the RJ metabolic and proteomic profiles were observed to vary with floral periods. Minor sugars (raffinose, erlose, and sucrose) and major RJ protein 5 (MRJP5) were identified among the discriminating components mainly contributing to the altered profiles. Water, crude protein, and the trans-10-hydroxy-2-decenoic acid (10-HDA) content fulfill the requirements of the International Organization for Standardization regardless of floral periods. Notably, the 10-HDA content increased 11.05%-19.65% during tea blooming. Moreover, changes in antioxidants resulted in significant difference in RJ antioxidant activity. The integrated omics data provide a detailed view of chemical composition for RJ quality evaluation.