Figure 9.

Cytokine concentration test. (a) IL-1β; (b) IL-6; (c) IL-18; (d) TNF-α. In cytokine test experiments, TNF-α, IL-1β, IL-6, IL-18 in the RAW264.7 cell culture supernatant were assayed with the corresponding sandwich enzyme-linked immunosorbent assay (ELISA). LPS was used as a positive reference drug in the test. Absorbance of each well at 450 nm was recorded using a microplate reader within 30 min. All tests were performed in triplicate and repeated at least once, and the results were expressed by their means ± SD (standard deviation). Statistical significance of the treatment effects was determined by Duncan’s multiple range t-test. * (p < 0.05), ** (p < 0.01)