Production, characterization and biomedical application of pyocyanin pigment produced by competent Pseudomonas species.

Pyocyanin is an extracellular diffusible pigment conferring virulence to Pseudomonas strains for their survival. Surge in antimicrobial resistance demands alternate potential candidates of biological origin. Combining the virulence and antagonistic potential, pyocyanin pigment shall be developed as a biocontrol agent with experimental studies. Media optimization and cross streak method were employed to screen the competent strain and identified using 16 S rRNA sequencing. Agar diffusion, broth dilution and MTT assay were adopted to determine the antimicrobial potential and biocompatibility of pyocyanin. Further, UV–vis spectrophotometry, GC-MS and 1H NMR analyses were used to validate the structural identity of pyocyanin. Results revealed that Potato glycerol broth supported maximum pyocyanin production from competent Pseudomonas aeruginosa WS1. Significant antimicrobial activity in a dose dependent fashion was observed with MIC 64 – 32 μg / mL. Cytotoxicity with IC 50 @ 108.5 mg L−1 was found to be associated with clumping and cell rounding with consistent lactate dehydrogenase (LDH) assay result. The mass spectrum (m/z) at 210 and N–CH 3 proton resonating at 1.4229 ppm and 7.4 – 7.5 ppm confirmed the condensed nitrogen aromatic ring of pyocyanin. These findings suggest that the combined virulence and antagonistic potential of pyocyanin interfering with the ETC may serve as a promising bio-control agent. [Display omitted] • Phenotypic and genotypic characterization of potential Pseudomonas strains. • Biochemical, molecular and structural elucidation of pyocyanin pigment. • Evaluation of clinical efficacy against toward bacteria and fungi. • Cytotoxicity study of pyocyanin for biomedical and clinical applications. [ABSTRACT FROM AUTHOR]