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.

Effects of covalent conjugation with quercetin and its glycosides on the structure and allergenicity of Bra c p from bee pollen.

Profilin family members are potential pan-allergens in foods, presenting public health hazards. However, studies on the allergenicity modification of profilin allergens are limited. Herein, quercetin and its glycosides (isoquercitrin and rutin) were applied to modify the allergenicity of a profilin allergen (Bra c p) from Brassica campestris bee pollen. Results showed that only quercetin can be closely covalently bound to Bra c p among the three, and the binding site was located at the Cys98 residue. After covalently conjunction, the relative content of α-helix structure in Bra c p was reduced by 40.05%, while random coil was increased by 42.89%; moreover, the Tyr and Phe residues in Bra c p were masked. These structural changes could alter the conformational antigenic epitopes of Bra c p, resulting in its allergenicity reduction. Our findings might provide a technical foundation for reducing the allergenicity of bee pollen and foods containing profilin family allergens.

Identification of characteristic markers for monofloral honey of Astragalus membranaceus var. mongholicus Hsiao: A combined untargeted and targeted MS-based study.

Astragalus membranaceus var. mongholicus Hsiao (Am) is a widely used traditional Chinese herbal medicine. The monofloral honey from Am plant nectar collected by honeybees (MH-Am) has potential medicinal activities. Quality control of MH-Am requires discovery of characteristic markers. In this study, calycosin and formononetin were identified as reliable chemical markers for MH-Am authentication, which were shared with its plant (P-Am), but absent in other honeys based on untargeted mass spectrometry (MS) analysis. The contents of calycosin and formononetin in MH-Am, other honeys and P-Am were determined through a targeted MS-based quantitative approach. Furthermore, free radical scavenging assays showed that calycosin functioned directly in the antioxidative activity of MH-Am. Thus, calycosin has great potential to be certified as a bioactive marker contributing to future quality control of commercial MH-Am products.