Flame Oxidation of Stainless Steel Felt Enhances Anodic Biofilm Formation and Current Output in Bioelectrochemical Systems

Biofilms on food-contact surfaces can lead to recurrent contamination. This work aimed to study the biofilm formation process on stainless steel plates used in the dairy industry: 304 surface finish 2B and electropolished; and the effect of a cleaning and disinfection process using alkaline (AEW) and neutral (NEW) electrolyzed water. Milk fouling during heat processing can lead to type A or B deposits, which were analyzed for composition, surface energy, thickness, and roughness, while the role of raw milk microbiota on biofilm development was investigated. Bacteria, yeasts, and lactic acid bacteria were detected using EUB-338, PF2, and Str-493 probes, respectively, whereas Lis-637 probe detected Listeria sp. The genetic complexity and diversity of biofilms varied according to biofilm maturation day, as evaluated by 16S rRNA gene sequence, denaturing gradient gel electrophoresis, and fluorescence in situ hybridization microscopy. From analysis of the experimental designs, a cleaning stage of 50 mg/L NaOH of AEW at 30 °C for 10 min, followed by disinfection using 50 mg/L total available chlorine of NEW at 20 °C for 5 min is a sustainable alternative process to prevent biofilm formation. Fluorescence microscopy was used to visualize the effectiveness of this process.

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Chemical sanitizers to control biofilms formed by two Pseudomonas species on stainless steel surface

Food Science and Technology ◽

10.1590/s0101-20612012005000008 ◽

2012 ◽

Vol 32 (1) ◽

pp. 142-150 ◽

Cited By ~ 13

Author(s):

Danila Soares Caixeta ◽

Thiago Henrique Scarpa ◽

Danilo Florisvaldo Brugnera ◽

Dieyckson Osvani Freire ◽

Eduardo Alves ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Stainless Steel ◽

Biofilm Formation ◽

Skim Milk ◽

304 Stainless Steel ◽

Stainless Steel Surface ◽

Aisi 304 ◽

Pseudomonas Species ◽

Sodium Dichloroisocyanurate ◽

Different Temperatures

The biofilm formation of Pseudomonas aeruginosa and Pseudomonas fluorescens on AISI 304 stainless steel in the presence of reconstituted skim milk under different temperatures was conducted, and the potential of three chemical sanitizers in removing the mono-species biofilms formed was compared. Pseudomonas aeruginosa cultivated in skim milk at 28 °C presented better growth rate (10.4 log CFU.mL-1) when compared with 3.7 and 4.2 log CFU.mL-1 for P. aeruginosa and P. fluorescens cultivated at 7 °C, respectively. Pseudomonas aeruginosa formed biofilm when cultivated at 28 °C. However, only the adhesion of P. aeruginosa and P. fluorescens was observed when incubated at 7 °C. The sodium dichloroisocyanurate was the most efficient sanitizer in the reduction of the adhered P. aeruginosa cells at 7 and 28 °C and those on the biofilm, respectively. The hydrogen peroxide was more effective in the reduction of adhered cells of P. fluorescens at 7 °C.

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Biofilm formation by Vibrio parahaemolyticus on different surfaces and its resistance to sodium hypochlorite

Ciência Rural ◽

10.1590/0103-8478cr20180612 ◽

2018 ◽

Vol 48 (12) ◽

Cited By ~ 3

Author(s):

Janaina Viana da Rosa ◽

Natália Volpato da Conceição ◽

Rita de Cássia dos Santos da Conceição ◽

Cláudio Dias Timm

Keyword(s):

Stainless Steel ◽

Sodium Hypochlorite ◽

Biofilm Formation ◽

Vibrio Parahaemolyticus ◽

High Density Polyethylene ◽

High Density ◽

Bacterial Populations ◽

Farfantepenaeus Paulensis ◽

Materials Used ◽

Fish Industry

ABSTRACT: Vibrio parahaemolyticus is an important pathogen for both fish industry and consumers. It forms biofilm which makes it difficult to eliminate this microorganism using sanitizers. This study aimed to assess biofilm formation on different surfaces and effect of biofilm on resistance to sanitizers. Eight isolates of biofilm-forming V. parahaemolyticus were tested for the ability to form biofilms on a number of surfaces including high density polyethylene, stainless steel, glass, exoskeleton of Farfantepenaeus paulensis (Pink Shrimp), and operculum of Micropogonias furnieri (Whitemouth Croaker). Efficiency of sanitizer sodium hypochlorite against the bacteria was evaluated in the biofilms formed on the surface of the materials used; out the eight strains analyzed four formed biofilm on different surfaces. The present study shows that there are variations between surfaces in terms of biofilm formation, with more than one bacterial strain being able to form biofilm on the surface of the operculum of M. furnieri and on high density polyethylene as well. One isolate formed biofilm on glass, and one isolate formed biofilm on stainless steel. Sanitizers reduced biofilm formation on all surfaces. Based on our findings, we concluded that V. parahaemolyticus isolates have different ability to form biofilm on different surfaces. No isolates formed biofilm on shrimp shells. Results of this study also showed that sodium hypochlorite eat a concentration of 20 parts per million (20ppm) of Cl2, albeit not able to eliminate bacteria reported in biofilms, is still capable of reducing bacterial populations.

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