Journal
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
Volume 394, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.ijfoodmicro.2023.110159
Keywords
Dual-species; Bacterial interactions; Surface coating; Food homogenate; MoO3; Nanomaterials
Categories
Ask authors/readers for more resources
This study investigated the influence of Pseudomonas fragi biofilm on Listeria monocytogenes and Campylo-bacter jejuni on stainless steel surfaces in different media. The biofilm of P. fragi produced more at 15℃ and in food homogenates. Co-cultivation with pathogens caused significant changes in L. monocytogenes and C. jejuni biofilm cells. A PVDF-HFP/PVP/MoO3 nanocomposite coating showed bactericidal activity in phosphate buffered saline and reduced bacterial counts in food homogenates. However, a high biofilm of P. fragi protected L. monocytogenes and C. jejuni against the functionalized nanocomposite surface in food homogenates.
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 Campylo-bacter jejuni NCTC 11168 was investigated at 5 degrees C and 15 degrees C on stainless steel in broth and food homogenates (fish or chicken meat). Stainless steel was then coated with PVDF-HFP/PVP/MoO3 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 degrees C than at 5 degrees 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/MoO3 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/MoO3 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.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available