Fermentative Production, Kinetic Analysis, Characterization, and Biological Evaluation of Phenazine‐1‐Carboxylic Acid from <i>Pseudomonas chlororaphis</i> subsp. <i>Aureofaciens</i>

ABSTRACT This study investigates phenazine‐1‐carboxylic acid (PCA) production by Pseudomonas chlororaphis subsp. aureofaciens under submerged batch fermentation. This nonpathogenic, flexible carbon‐utilizing strain was selected as a safer and industrially adaptable PCA producer. Chemical and physical parameters were optimized, and phenazines were isolated by chloroform extraction followed by adsorption chromatography and characterized using UV–vis, FTIR, and 1 H‐NMR analyses. PCA production was identified as growth‐associated, yielding 129.45 µg/mL—comparable to wild‐type Pseudomonas strains despite the use of low‐cost glycerol medium‐highlighting the process's industrial relevance. Key kinetic parameters were determined as Y XS = 0.64 mg/mg, Y PS = 0.12 mg/mg, Y PX = 0.35 mg/mg, and μ = 0.39 h − 1 . PCA exhibited antimicrobial activity against Klebsiella pneumoniae (10 mm) and Micrococcus luteus (22 mm) at 150 µg/mL. Cytotoxicity was evaluated via MTT assay on A549 and SKOV3 cells, yielding IC 50 values of 17.30 ± 1.72, 13.04 ± 0.76, and 5.69 ± 0.35 µg/mL at 24, 48, and 72 h, respectively, with notable effects also observed in SKOV3 cells. Overall, the findings demonstrate that PCA possesses significant antimicrobial and anticancer potential, supporting its further development as a natural bioactive compound.