Rapid discrimination of Lentilactobacillus parabuchneri biofilms via in situ infrared spectroscopy

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 304; p. 123391
• Main Authors: Bajrami, Diellza, Sarquis, Agustina, Ladero, Victor M., Fernández, María, Mizaikoff, Boris
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.01.2024
• Subjects: Biofilm formation; Cheese-isolated strains; Extracellular polymeric substances; Infrared attenuated total reflection spectroscopy; Lentilactobacillus parabuchneri; Luminescence sensing; Multivariate data analysis/classification; Partial least square-discriminant analysis; Principal component analysis; Lentilactobacillus parabuchneri; Extracellular polymeric substances; Luminescence sensing; Cheese-isolated strains; Multivariate data analysis/classification; Biofilm formation; Partial least square-discriminant analysis; Infrared attenuated total reflection spectroscopy; Principal component analysis
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2023.123391

[Display omitted] •Six cheese-isolated histamine-producing strains were examined as food contaminants.•In situ mid-infrared spectroscopy and fluorescence to understand the biofilm behavior.•Molecular mechanisms studies involved in Lentilactobacillus parabuchneri biofilm growth.•Real-time and long-term monitoring led to discrimination of biofilms.•Chemometric models rapidly differentiate weak, moderate and strong biofilm producers. Microbial contamination in food industry is a source of foodborne illnesses and biofilm-related diseases. In particular, biogenic amines (BAs) accumulated in fermented foods via lactic acid bacterial activity exert toxic effects on human health. Among these, biofilms of histamine-producer Lentilactobacillus parabuchneri strains adherent at food processing equipment surfaces can cause food spoilage and poisoning. Understanding the chain of contamination is closely related to elucidating molecular mechanisms of biofilm formation. In the present study, an innovative approach using integrated chemical sensing technologies is demonstrated to fundamentally understand the temporal behavior of biofilms at the molecular level by combining mid-infrared (MIR) spectroscopy and fluorescence sensing strategies. Using these concepts, the biofilm forming capacity of six cheese-isolated L. parabuchneri strains (IPLA 11151, 11150, 11129, 11125, 11122 and 11117) was examined. The cut-off values for the biofilm production ability of each strain were quantified using crystal violet (CV) assays. Real-time infrared attenuated total reflection spectroscopy (IR-ATR) combined with fluorescence quenching oxygen sensing provides insight into distinct molecular mechanisms for each strain. IR spectra showed significant changes in characteristic bands of amides, lactate, nucleic acids, and extracellular polymeric substances (i.e., lipopolysaccharides, phospholipids, phosphodiester, peptidoglycan, etc.), which are major contributors to biofilm maturation involved in the initial adhesion processes. Chemometric methods including principal component analysis and partial least square-discriminant analysis facilitated the rapid determination and classification of cheese isolated L. parabuchneri strains unambiguously differentiating the IR signatures based on their ability to produce biofilm. All biofilms were morphologically characterized by confocal laser scanning microscopy on relevant industrial equipment surfaces. In summary, this innovative approach combining MIR spectroscopy with luminescence sensing enables real-time insight into the molecular composition and formation of L. parabuchneri biofilms.