20.500.12556/RUL-145900 Pseudomonas fragi biofilm on stainless steel (at low temperatures) affects the survival of Campylobacter jejuni and Listeria monocytogenes and their control by a polymer molybdenum oxide nanocomposite coating Pseudomonas spp. are widely distributed bacteria on surfaces in the food production and processing environment, where they form extracellular polymeric substance rich biofilms that interact with other bacteria. In this study, the influence of biofilm of Pseudomonas fragi ATCC 4973 on Listeria monocytogenes ATCC 19115 and Campylobacter jejuni NCTC 11168 was investigated at 5 °C and 15 °C on stainless steel in broth and food homogenates (fish or chicken meat). Stainless steel was then coated with PVDF-HFP/PVP/MoO$_3$ nanocomposite and examined for surface changes (scanning electron microscope, static contact angle, Vickers hardness and elastic modulus). The effect of the prepared nanocomposite coating on P. fragi and on L. monocytogenes and C. jejuni was evaluated in mono- and co-culture. P. fragi produced more biofilm at 15 °C than at 5 °C, especially when food homogenates were used as growth media. Co-cultivation with pathogens did not affect biofilm production by P. fragi, but significant changes were observed in L. monocytogenes and C. jejuni, resulting in a decrease and increase, respectively, in the determined number of culturable biofilm cells. The first change was probably due to competition for the surface, and the second to the oxygen gradient. Stainless steel was then coated with a PVDF-HFP/PVP/MoO$_3$ nanocomposite, which was characterised by lower roughness and higher wettability, but lower hardness compared to uncoated stainless steel. The prepared nanocoating showed bactericidal activity when tested in phosphate buffered saline. When used in food homogenates, a reduction of over 95 % in bacterial counts was observed. An abundant biofilm of P. fragi proved protective to L. monocytogenes and C. jejuni against the functionalised nanocomposite surface when tested in food homogenates. The control of spoilage Pseudomonas spp., which are common in the food production and processing environment, is important for reducing the contamination of food with spoilage bacteria and with pathogens such as L. monocytogenes and C. jejuni, which may be present in the same environment. The PVDF-HFP/PVP/MoO$_3$ nanocomposite showed good potential for use as a coating for food contact surfaces, but possible migration of nanoparticles from the nanocomposite coating to food should be evaluated before its commercial use. dual-species bacterial interactions surface coating food homogenate nanomaterials MoO$_3$ Pseudomonas fragi biofilm bakterijske interakcije jeklene površine nanodelci kvar živil protimikrobno delovanje nanokompozitna prevleka true false true Angleški jezik Slovenski jezik Članek v reviji 2023-05-17 13:39:08 2023-05-17 13:39:15 2025-02-21 11:06:02 0000-00-00 00:00:00 2023 0 0 11 str. art. 110159 Vol. 394 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 579.67 0168-1605 10.1016/j.ijfoodmicro.2023.110159 144534531 RAZ_Sternisa_Meta_2023.pdf RAZ_Sternisa_Meta_2023.pdf 1 C5679FDC0C88E99FE85ADE3746550BAF b6a28994f9f39f2a8f9d6f50db9961ddd9c0bef6b1b4175c3c4ea8814b0c069b 8fcf6d21-f4a9-11ed-a314-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=168982 https://www.sciencedirect.com/science/article/pii/S0168160523000752 1 3117f898-f4a7-11ed-a314-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=168980 Biotehniška fakulteta Fakulteta za strojništvo 0 0 0