Anti-inflammatory function of 4-tert-butylphenyl salicylate through down-regulation of the NF-kappa B pathway.

The salicylic acid derivative 4-tert-butylphenyl salicylate (4-TBPS) possesses anti-inflammatory activity. We demonstrated this and elucidated the mechanisms involved by using the lipopolysaccharide-stimulated Raw 264.7 mouse macrophage model. The 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, western blot, enzyme-linked immunosorbent assay, and reverse transcriptase-polymerase chain reaction were performed to explore 4-TBPS anti-inflammatory activity. We found that 4-TBPS decreased nitric oxide production without cytotoxic effects on macrophages and reduced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 in a dose-dependent manner. Additionally, mRNA expressions of iNOS and COX-2 significantly reduced, with concentrations between 1 and 15 µg/ml. Furthermore, 4-TBPS significantly inhibited the production of pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin- (IL)-1ß, and IL-6. Moreover, mRNA gene expression of TNF-α, IL-1ß, and IL-6 was attenuated in a dose-dependent manner. 4-TBPS potently inhibited translocation of nuclear factor-κB (NF-κB) into the nucleus by degrading IκB kinase (IκBα) following its phosphorylation, thereby causing NF-κB to remain inactive. Collectively, our data indicate that 4-TBPS significantly (p < 0.01) targets the inflammatory response of macrophages via inhibition of iNOS, COX-2, TNF-α, IL-1ß, and IL-6 through downregulation of the NF-κB pathway. This indicates that 4-TBPS may have therapeutic potential in inflammatory disorders.

Statistical optimization of a multivariate fermentation process for enhancing antibiotic activity of Streptomyces sp. CS392.

Antibiotic activity against various gram positive bacteria including Staphylococcus aureus and Enterococcus was ascertained from a soil-isolated microbial strain Streptomyces sp. CS392. The antibiotic activity of the strain was maximized by using a dual-stage, multivariate statistical optimization framework based on the response surface methodology considering a lab-scale fermentation process. Multiple nutrient constituents of the fermentation broth were jointly optimized in the first stage, while the fermentation culture conditions were optimized in the subsequent stage. Based on the empirical models derived from the dual-stage statistical optimization framework, 39.79 % of cumulative enhancement in the antibiotic activity was obtained (analytically) at the concurrent optimal settings (Optimal nutrient composition for the first stage of optimization: 29.82 glucose, 7.6 peptone, 4.678 MgCl2 and 0.5005 g/l casamino acid; and optimal fermentation condition for the second stage of optimization: incubation period 47.55 h; incubation temperature 29.15 °C; and pH 8.36). The analytically depicted enhancement in the antibiotic activity was validated experimentally.