Pyocyanin

Pyocyanin has been used as a biomarker to detect Pseudomonas aeruginosa.

Pyocyanin, a blue-green pigment belonging to phenazine pigments, is a redox-active phenazine. Pyocyanin is an electron receptor, which stimulates redox cycling in bacteria, liver cells, and human epithlial cell lines. Pyocyanin enhances the oxidative metabolism, which in turn increases the formation of intracellular reactive oxygen species (ROS) via reduction of NADPH. Pyocyanin also increases the release of IL-8 by airway epithelial cells both in vitro and in vivo. This involves signal transduction pathways that include oxidants, protein tyrosine kinases, and MAP kinases. IL-8 secretion by these cells is in synergy with inflammatory cytokines. Pyocyanin has been shown to accelerate neutrophil apoptosis in vitro, resulting in resolution of acute inflammation, which is beneficial for bacteria survival.

For the preparation of an aqueous solution, dissolve pyocyanin in ethanol using 10% of the final required volume and then add distilled water to complete the volume.