AUTHOR=Singh Niharika , Gulhane Rohini Devidas , Singh Anamika , Goel Maitri , Udelal Pudke Payal , Sangwan Vikas , Sihag Manvesh Kumar , Goel Gunjan , Panwar Harsh , Puniya Anil Kumar 

TITLE=Exploring the antimicrobial potential of lactobacilli against early-stage and mature biofilms of Staphylococcus aureus and Pseudomonas aeruginosa

JOURNAL=Frontiers in Chemistry

VOLUME=Volume 13 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2025.1425666

DOI=10.3389/fchem.2025.1425666

ISSN=2296-2646

ABSTRACT=Bacterial biofilms are dynamic, complex, and very adaptive, and they can cause health problems in both humans and animals while also posing a serious threat to various industries. This study explores the potential of cell-free preparations of lactobacilli isolated from breast milk (HM; n = 11) and infant fecal (IF; n = 15) samples to impact the growth of Staphylococcus aureus and Pseudomonas aeruginosa biofilms. The anti-biofilm activity of three distinct cell-free preparations, namely, untreated cell-free supernatant (CFS), pH-neutralized CFS (N-CFS), and heat-treated CFS (H-CFS), was examined against both early-stage and mature biofilms. The post-incubation strategy examined the impact on mature biofilms, while the co-incubation treatment assessed the impact of CFS on adhesion and initial colonization. Compared to post-incubation treatment (HM3, 67.12%), the CFSs exhibited greater inhibitory activity during co-incubation (IF9, 85.19%). Based on the findings, untreated CFS exhibited the most promising biofilm inactivation, although its activity was not completely lost upon pH neutralization and heat treatment. Treatment with H-CFSs and N-CFSs moderately reduced the population of S. aureus and P. aeruginosa bacterial cells within the biofilm by 40%–60%. Microscopic observations showed that after CFS treatment, the integrity of the biofilm conformation was disrupted. According to principal component analysis (PCA) (significance level at p < 0.05), the most promising anti-biofilm activity against both test pathogens was found in the CFS of Lacticaseibacillus paracasei HM1.