Development and validation of LC/MS/MS quantification method for plantaricins in culture supernatant

Bacteriocins are a group of small antimicrobial peptides that are ribosomally synthesized and secreted by lactic acid bacteria (LAB). These peptides exhibit high inhibitory activity at low concentrations in the nanomolar range and possess relatively narrow-spectrum antimicrobial activity, making them attractive for various applications, especially as natural food preservatives. Here, we report a novel nano-LC/MS-based analysis method for the simultaneous quantification of plantaricin E, F, J, and K in the culture supernatants of their producer LAB strain ABG0035. This method enables accurate quantification of the bacteriocins of interest, even in the presence of high concentrations of sample matrices commonly found in the culture medium. Furthermore, this approach is promising for the analysis of bacteriocins in diverse environments, including cultured bacteria and food matrices.