title: Inactivation of Lactobacillus rhamnosus GG by fixation modifies its probiotic properties.
abstract: Probiotics are microorganisms that have beneficial effects on the host and are safe for oral intake in a suitable dose. However, there are situations in which the administration of living microorganisms poses a risk for immunocompromised host. The objective of this study was to evaluate the influence of several fixation methods on selected biological properties of Lactobacillus rhamnosus GG that are relevant to its probiotic action. Fixation of the bacterial cells with ethanol, 2-propanol, glutaraldehyde, paraformaldehyde, and heat treatment resulted in a significant decrease of alkaline phosphatase, peroxidase, and β-galactosidase activities. Most of the fixation procedures reduced bacterial cell hydrophobicity and increased adhesion capacity. The fixation procedures resulted in a different perception of the bacterial cells by enterocytes, which was shown as changes in gene expression in enterocytes. The results show that some procedures of inactivation allow a fraction of the enzymatic activity to be maintained. The adhesion properties of the bacterial cells were enhanced, but the response of enterocytes to fixed cells was different than to live bacteria. Inactivation allows maintenance and modification of some of the properties of the bacterial cells.
authors.affiliation: Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.|Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.
authors.forename: C
authors.initials: C
authors.lastname: Markowicz
authors.affiliation: Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.|Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.
authors.forename: P
authors.initials: P
authors.lastname: Kubiak
authors.affiliation: Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.|Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.
authors.forename: W
authors.initials: W
authors.lastname: Grajek
authors.affiliation: Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.|Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48 60-627 Poznan, Poland.
authors.forename: M T
authors.initials: MT
authors.lastname: Schmidt
mesh_terms: D001422:Bacterial Adhesion; D018938:Caco-2 Cells; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D016209:Interleukin-8 / Q000032:analysis; D052201:Lacticaseibacillus rhamnosus; D019936:Probiotics / Q000494:pharmacology*
chemical_list: D016209:Interleukin-8
keywords: adhesion; adhérence; bacteria; bactéries; enterocyte; entérocyte; expression génique; gene expression; inactivation