2.9. Determination of Proinflammatory Cytokine Levels

The concentrations of IL-6 and TNF-α were determined by using ELISA. RAW 264.7 cells (1 × 10⁶ cells/well) were seeded in 6-well plates and preincubated for 16 h; subsequently, the samples were treated with LPS (1 μg/mL) for 24 h to induce the production of cytokines. The supernatant was evaluated using an ELISA kit (Youngin Frontier, Seoul, Korea) in accordance with the manufacturer's instructions. The cytokine concentrations were quantified by measuring the absorbance at 450 nm.