Lu, C.-y. | bioRxiv Science

bioRxiv2025

Metabolite Profiling of Epimedium sagittatum Bee Pollen: Identified Bioactive Flavonoids with Multi-Disease Functional Food Potential

Epimedium sagittatum bee pollen (EBP) is a bee pollen product of a medicinal plant, but its chemical characteristics remain unclear. In this study, EBP was systematically characterized by biochemical analysis and UPLC-MS/MS, using Brassica rapa bee pollen (BBP), Camellia sinensis bee pollen (CBP), and Epimedium leaves for compari-son. A total of 1,073 secondary metabolites were identified in EBP, mainly flavonoids (330, 30.8%) and phenolic acids (165, 15.3%). EBP showed the highest total flavonoid content among the three bee pollen types (4.75 mg/g) and was clearly separated from BBP and CBP in multivariate analysis. EBP contained 19 unique metabolites, fewer than CBP (271), but these included several high-content flavonoid compounds, such as cacticin, brassicin, and tricetin-4'-methyl ether-3'-{beta}-D-glucoside. Differential metabolite analysis identified 449 and 1,085 metabolites that differed between EBP and BBP, re-spectively, with flavonoid compounds forming the main differential class. Among the shared differential metabolites, 45 flavonoids were consistently higher in EBP, in-cluding kaempferol, tamarixetin, and sinensetin. Network pharmacology screening further suggested that flavonoid metabolites, especially kaempferol, tamarixetin, and sinensetin, deserve particular attention in future studies of EBP. Compared with Epimedium leaves, characteristic leaf flavonoids such as icariin and epimedins A-C were present at very low levels or were not detected in EBP. Overall, EBP is charac-terized by a distinct, relatively concentrated flavonoid chemical profile, distinct from both common commercial bee pollens and Epimedium medicinal tissues. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=160 SRC="FIGDIR/small/679240v2_ufig1.gif" ALT="Figure 1"> View larger version (56K): org.highwire.dtl.DTLVardef@1587d35org.highwire.dtl.DTLVardef@8461d6org.highwire.dtl.DTLVardef@1336149org.highwire.dtl.DTLVardef@381ae8_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗

bioRxiv2019

Combination antibiotic delivery in PMMA provides sustained broad-spectrum antimicrobial activity and allows for post-implantation refilling

Antibiotics are commonly added to poly(methyl methacrylate) (PMMA) by surgeons to locally treat infections such as in bone cement for joint replacement surgeries, but also as implantable antimicrobial "beads". However, this strategy is of limited value in high risk patients where infections can be recurrent or chronic and otherwise hard to treat. Also when only one drug is incorporated and applied toward poly-microbial infections (multiple bacterial species), there is a high risk that bacteria can develop antibiotic resistance. To combat these limitations, we developed a combination-antibiotic PMMA composite system comprised of rifampicin-filled {beta}-cyclodextrin ({beta}-CD) microparticles added into PMMA filled with a second drug. Different formulations were evaluated through Zone-of-Inhibition, drug activity, antibiotic release and re-filling, as well as mechanical studies. Our combination-antibiotic PMMA composite system achieved up to an eight-fold increase in duration of antimicrobial activity in comparison to clinically used antibiotic-filled PMMA. Inclusion of CD microparticles also allowed for refilling of additional antibiotics after simulated implantation, resulting in additional windows of therapeutic efficacy. Mechanical testing showed that our tested formulations did have a small, but significant decrease in mechanical properties when compared to unmodified controls. While further studies are needed to determine whether the tested formulations are still suitable for load-bearing applications (e.g. bone cement), our composites are certainly amenable for a variety of non-load bearing applications (e.g. antimicrobial "beads" and temporary spacer in two-stage arthroscopic revisions).

bioengineering↗