Butterfly-layered covalent organic polymers loaded with essential oils of <i>Cyperus rotundus</i> L.

Abstract Cyperus rotundus L. essential oil (CEO) was loaded into covalent organic polymer materials (PdIs) and characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller theory (BET), and Thermogravimetric Analysis (TG). The main components of CEO were identified as cyperenone (13.43 %), cyperene (10.01 %), α -cyperone (5.83 %), caryophyllene oxide (3.15 %), Zierone (2.97 %), and Cyperene epoxide (2.07 %). The stability of PdIs/CEO was systematically investigated. The antioxidant activities of CEO and PdIs/CEO were evaluated based on their ability to scavenge DPPH and ABTS free radicals. A CCK-8 assay was employed to determine the concentrations of sample, and a lipopolysaccharide (LPS)-induced RAW264.7 cell model was established to assess their anti-inflammatory effects. Both CEO and PdIs/CEO exhibited strong antioxidant activity. They significantly inhibited the production of nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). At a concentration of 150 μg/mL, the maximum inhibition rates for TNF-α, and IL-6 reached 91.63 % and 96.23 %, respectively. This study demonstrates that PdIs/CEO has promising potential for applications in food, pharmaceutical, and related fields.