Figure 3.

(A) Structures and nomenclature for Bauer Ketones identified in Fraction 3 from E. pallida. (B) Significant inhibition of LPS induced PGE₂ and NO production in RAW264.7 cells after treatment with chemically synthesized Bauer Ketones 21 and 23. The black bars represent PGE₂ levels and the white bars represent NO levels after induction with 1 μg/ml LPS and treatment with a ketone (n = 3). All treatments + LPS were compared to media + DMSO + LPS control that was set at 100 % PGE₂ production (3.7 ng/ml) and NO production (12.4 ng/ml). Treatments were also performed without LPS induction showing significant reduction of PGE₂ production with Bauer Ketone 21 at 1 μM (p = 0.046). The treatments without LPS were compared to the media + DMSO control set at 100 % PGE₂ production (0.02 ng/ml). There was no significant difference in NO production in treatments without LPS. Quercetin was used as a positive control for both studies and showed significant inhibition of PGE₂ and NO production (p<0.0001). * and ** are representative of p<0.05 and p<0.001. Each bar represents % of control ± standard error. Parallel cytotoxicity screens were conducted yielding no significant cytotoxicity with any of the chemically synthesized Bauer Ketones (data not shown)