Impairment of Cronobacter sakazakii and Listeria monocytogenes biofilms by cell-free preparations of lactobacilli of goat milk origin

• Published in: Folia microbiologica Vol. 65; no. 1; pp. 185 - 196
• Main Authors: Singh, Niharika, Kaur, Ravinder, Singh, Brij Pal, Rokana, Namita, Goel, Gunjan, Puniya, Anil Kumar, Panwar, Harsh
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.02.2020; Springer Nature B.V
• Subjects: Antimicrobial agents; Applied Microbiology; Bacterial diseases; Biofilms; Biomedical and Life Sciences; Cronobacter sakazakii; Environmental Engineering/Biotechnology; Fluorescence; Food industry; Goat's milk; Goats; Health services; Heat treatment; Immunology; Lactobacilli; Lactobacillus; Life Sciences; Listeria; Listeria monocytogenes; Medical treatment; Microbiology; Microorganisms; Milk; Original Article; Pathogenesis; Anti-biofilm; Probiotics; Lactic acid bacteria; Listeria monocytogenes; Cronobacter sakazakii
• ISSN: 0015-5632; 1874-9356
• DOI: 10.1007/s12223-019-00721-3

Biofilm-associated bacterial infections represent one of the major threats to modern medical treatments. Bacteria encased in biofilm matrix are more resistant towards antimicrobials and thus the capability of microbes to persist and nurture in a biofilm seems to be the foremost aspect of pathogenesis and therapeutic failure. Therefore, there is a pressing demand for new drugs active against microbial biofilms. In the current study, anti-biofilm potential of Lactobacillus spp. cell-free supernatants (CFSs) against Cronobacter sakazakii and Listeria monocytogenes was characterized using crystal violet staining and MTT assay. CFSs of goat milk origin lactobacilli not only prevented biofilm formation but also disrupted preformed biofilms. Neutralized and heat-treated preparations of Lactobacillus CFSs also inhibited biofilm formation by test pathogens. The results were quantitatively confirmed by light and fluorescent microscopy observations. Biofilms developed under static conditions displayed typical compact microcolonies with uniform distribution over the surface, while upon CFS challenge, biofilms were disrupted with presence of dead cells. These findings highlight the anti-biofilm potency of Lactobacillus spp. strains of goat milk origin and their potential application in food industries.