title: Change in cell surface properties of Lactobacillus casei under heat shock treatment.
abstract: We undertake this study in the aim to give new insight about the change in cellular physiological state under heat shock treatment and probiotic strain screening procedure. Different cell properties have been studied like adhesive ability to biotic and abiotic surfaces, the cell surface hydrophobicity and the fatty acids profiles. Compared to the normal cells, the heated cells increased their adhesive ability to biotic surface. However, the adhesion to abiotic surface was decreased. The cell surface hydrophobicity of the heated strains showed a significant decrease (P < 0.05). Our data revealed that high temperature change the fatty acids profiles of the treated cells, especially the proportions of unsaturated and saturated fatty acid. In fact, the ratio of saturated to unsaturated fatty acids of the heated Lactobacillus casei cells was significantly higher than that of the control cells (P < 0.05). The present finding could firstly add new insight about the response of probiotic to stressful conditions, such us the important role of cell membrane, considered as the first main structure to be damaged by physicochemical stress, in stress resistance because of their composition that can change in adaptation to harsh conditions. Secondly, there is no relationship between changes in membrane composition and fluidity induced by heat shock treatment and adhesion to biotic and abiotic surface.
authors.affiliation: Laboratory of Analysis, Treatment and Valorization of the Pollutants of the Environment and Products, Faculty of Pharmacy, University of Monastir, Monastir Avicenne Street, Monastir 5000, Tunisia najla_haddaji@yahoo.fr.
authors.forename: Najla
authors.initials: N
authors.lastname: Haddaji
authors.affiliation: Laboratory of Analysis, Treatment and Valorization of the Pollutants of the Environment and Products, Faculty of Pharmacy, University of Monastir, Monastir Avicenne Street, Monastir 5000, Tunisia.
authors.forename: Abdel Karim
authors.initials: AK
authors.lastname: Mahdhi
authors.affiliation: Laboratory of Analysis, Treatment and Valorization of the Pollutants of the Environment and Products, Faculty of Pharmacy, University of Monastir, Monastir Avicenne Street, Monastir 5000, Tunisia.
authors.forename: Boubaker
authors.initials: B
authors.lastname: Krifi
authors.affiliation: Laboratory of Biophysics, Faculty of Medicine, University of Monastir, Monastir Avicenne Street, Monastir 5000, Tunisia.
authors.forename: Manel Ben
authors.initials: MB
authors.lastname: Ismail
authors.affiliation: Laboratory of Analysis, Treatment and Valorization of the Pollutants of the Environment and Products, Faculty of Pharmacy, University of Monastir, Monastir Avicenne Street, Monastir 5000, Tunisia.
authors.forename: Amina
authors.initials: A
authors.lastname: Bakhrouf
mesh_terms: D000222:Adaptation, Physiological; D001422:Bacterial Adhesion; D002462:Cell Membrane / Q000502:physiology*; D005227:Fatty Acids / Q000032:analysis*; D005231:Fatty Acids, Unsaturated / Q000032:analysis; D006367:HeLa Cells; D018869:Heat-Shock Response; D006358:Hot Temperature; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007780:Lacticaseibacillus casei / Q000166:cytology / Q000502:physiology* / Q000648:ultrastructure; D019936:Probiotics; D013499:Surface Properties
chemical_list: D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated
keywords: Lactobacillus casei; adhesion; fatty acids; heat shock; hydrophobicity; probiotic