Abstract:

High-pressure homogenization (HPH) has been proposed to be applied directly to lactic acid bacterial cells at sublethal levels to enhance some functional properties. As the principal target of HPH are the cell surface envelope structures, the aim of this work was to study the effect of a HPH treatment, applied at 50 MPa, on cell membrane stress responses of already-known functional strains, isolated from Argentinean products. Specifically, the membrane fatty acid composition of cells before and after the sublethal treatment was investigated, and the results showed that plasma membranes, their level of unsaturation and their composition are involved in response mechanisms adopted by microbial cells when subjected to a sublethal HPH stress. In fact, the data obtained demonstrated that the treatment was able to modify the fatty acid profile of the different strains, although a uniform response was not observed. Further studies are necessary both to elucidate the role of each fatty acid in the cell response mechanisms and to clarify the changes in membrane compositions induced by HPH treatment also in relation to the applicative potential of this technique.

Author affiliation: Tabanelli, G.. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia

Author affiliation: Patrignani, Francesca. Universidad de Bologna; Italia

Author affiliation: Gardini, F.. Universidad de Bologna; Italia. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia

Author affiliation: Vinderola, Celso Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina

Author affiliation: Reinheimer, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina

Author affiliation: Grazia, L.. Universidad de Bologna; Italia. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia

Author affiliation: Lanciotti, R.. Universidad de Bologna; Italia. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia

Abstract:

High-pressure homogenization (HPH) has been proposed to be applied directly to lactic acid bacterial cells at sublethal levels to enhance some functional properties. As the principal target of HPH are the cell surface envelope structures, the aim of this work was to study the effect of a HPH treatment, applied at 50 MPa, on cell membrane stress responses of alreadyknown functional strains, isolated from Argentinean products. Specifically, the membrane fatty acid composition of cells before and after the sublethal treatment was investigated, and the results showed that plasma membranes, their level of unsaturation and their composition are involved in response mechanisms adopted by microbial cells when subjected to a sublethal HPH stress. In fact, the data obtained demonstrated that the treatment was able to modify the fatty acid profile of the different strains, although a uniform response was not observed. Further studies are necessary both to elucidate the role of each fatty acid in the cell response mechanisms and to clarify the changes in membrane compositions induced by HPH treatment also in relation to the applicative potential of this technique.

Author affiliation: Tabanelli, G.. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia

Author affiliation: Patrignani, F. University of Bologna. Department of Agri-Food Science and Technologies, Alma Mater Studiorum; Italia

Author affiliation: Gardini, F.. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia. University of Bologna. Department of Agri-Food Science and Technologies, Alma Mater Studiorum; Italia

Author affiliation: Vinderola, Celso Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Lactologia Industrial; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina

Author affiliation: Reinheimer, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Lactologia Industrial; Argentina. Universidad Nacional del Sur. Departamento de Ingenieria Quimica; Argentina

Author affiliation: Grazia, L.. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia. University of Bologna. Department of Agri-Food Science and Technologies, Alma Mater Studiorum; Italia

Author affiliation: Lanciotti, R.. Inter-Departmental Centre of Industrial Agri-Food Research (CIRI Agroalimentare); Italia. University of Bologna. Department of Agri-Food Science and Technologies, Alma Mater Studiorum; Italia