Category Archives: Biofilm

Research – Impact of gas ultrafine bubbles on the potency of chlorine solutions against Listeria monocytogenes biofilms

Posted on December 1, 2021 by | Leave a comment

Ultrafine bubble technology is a novel concept in food safety that can improve the potency of antimicrobials against biofilms. This study was conducted to evaluate the impact of gas (air, CO2, or N2) ultrafine bubbles incorporation in 100 and 200 ppm chlorine (Cl2) solutions to inactivate fresh Listeria monocytogenes biofilms on stainless steel. Listeria monocytogenes biofilms were grown on stainless steel coupons through static incubation at 37°C for 72 hr by immersing in L. monocytogenes inoculated brain heart infusion (BHI) broth. The coupons were treated by dipping in water or Cl2 solutions with or without ultrafine bubbles for 1 min. Random pre-determined areas on coupons were swabbed into Dey–Engley neutralizing broth before and after treatments and enumerated using BHI agar. Air and CO2 nanobubbles in 100 ppm Cl2 resulted in greater log reductions (5.0 and 4.9 log CFU/cm2, respectively) in L. monocytogenes biofilms compared with 100 ppm Cl2 without gas ultrafine bubbles (3.7 log CFU/cm2). Incorporation of air, CO2, and N2 ultrafine bubbles in water and 200 ppm Cl2 did not have any impact on the efficacy of biofilm inactivation.

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Posted in Biofilm, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Technology, Listeria, Listeria monocytogenes, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research, Technology

Research – Research expands ability to detect, kill harmful biofilms

Posted on November 9, 2021 by | Leave a comment

Food Safety News

Food safety practices evolve as new technology and knowledge of the pathogens that spread foodborne illnesses becomes available.

In recent years, researchers have increasingly focused efforts on biofilm and its ability to thrive in nature and in food production and processing facilities. Biofilm is formed by a pathogen — or more often, a mixture of different pathogens — that builds a protective layer using extracellular polymeric substances (EPS).

A majority of foodborne illnesses can be traced to pathogens housed in biofilms, according to food safety research. Academics and food trade associations have stepped up efforts in recent years to learn more about biofilm, which naturally fights efforts to sanitize food contact surfaces in processing and manufacturing facilities.

Recent studies have looked at products and practices to eradicate or control biofilms in different segments of the food industry, from produce to meat processing and poultry farms.

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Posted in Biofilm, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Safety, Food Safety Alert, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research, Uncategorized

Research – Biofilms are a concern across the entire food supply chain

Posted on November 6, 2021 by | Leave a comment

Food Safety News

kswfoodworld biofilm

Biofilm, which is a cluster of pathogens encased in a protective matrix, is a common enemy across diverse food manufacturing industries.

From dairy, produce, meat, poultry, ready-to-eat deli foods and other products, biofilm is a concern at the farm level and at processing and manufacturing plants.

The protective layers generated by pathogens that create the biofilm, known as extracellular polymeric substances (EPS), resist sanitation efforts and are adept at spreading in moist environments, through a process known as “seeding dispersal.” According to Sterilex Industries, which offers products to treat biofilms and the pathogens they harbor, seeding dispersal is similar to a dandelion releasing seeds to encourage species growth.

Although forming biofilm is a natural process that pathogens — including those commonly leading to foodborne illness outbreaks, such as Shiga-toxin producing E. coli, Listeria monocytogenes and Salmonella — use to survive, industry food safety plans and government regulations don’t necessarily focus on biofilm and how to eradicate it.

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Posted in Biofilm, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Listeria, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research, Salmonella, STEC, STEC E.coli

Research – New Trends in Photodynamic Inactivation (PDI) Combating Biofilms in the Food Industry—A Review

Posted on October 26, 2021 by | Leave a comment

MDPI

Biofilms cause problems in the food industry due to their persistence and incompetent hygiene processing technologies. Interest in photodynamic inactivation (PDI) for combating biofilms has increased in recent years. This technique can induce microbial cell death, reduce cell attachment, ruin biofilm biomolecules and eradicate structured biofilms without inducing microbial resistance. This review addresses microbial challenges posed by biofilms in food environments and highlights the advantages of PDI in preventing and eradicating microbial biofilm communities. Current findings of the antibiofilm efficiencies of this technique are summarized. Additionally, emphasis is given to its potential mechanisms and factors capable of influencing biofilm communities, as well as promising hurdle strategies.

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Posted in Biofilm, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Technology, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, PDI, photodynamic inactivation, Research

Research – Biofilms bring safety challenges to food companies

Posted on October 25, 2021 by | Leave a comment

Food Safety News

In the first installment of this series with Sterilex, Food Safety News explores what biofilms are and their unique resistance to attempts to kill the pathogens they protect.

Food processors and manufacturers know the environments in which they operate are friendly to organisms that can taint their products, potentially leading to foodborne illness outbreaks.

Food safety plans and specific good manufacturing processes outlined in those documents are designed to combat common pathogens — including strains of Listeria, Salmonella and E. coli — that could lead to recalls or outbreaks.

Whether or not food safety plans specifically mention “biofilms,” in many cases they are the root cause of contamination in food facilities. Approximately 60 percent of foodborne illness outbreaks are caused by biofilms, according to food safety research.

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Posted in Biofilm, food contamination, Food Hazard, Food Hygiene, Food Inspections, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Safety, Food Testing, Research

Research – Biofilm Formation Ability of Arcobacter-like and Campylobacter Strains under Different Conditions and on Food Processing Materials

Posted on October 2, 2021 by | Leave a comment

MDPI

kswfoodworld biofilm

Campylobacter jejuni is the most frequent cause of bacterial gastrointestinal food-borne infection worldwide. The transmission of Campylobacter and Arcobacter-like species is often made possible by their ability to adhere to various abiotic surfaces. This study is focused on monitoring the biofilm ability of 69 strains of Campylobacter spp. and lesser described species of the Arcobacteraceae family isolated from food, water, and clinical samples within the Czech Republic. Biofilm formation was monitored and evaluated under an aerobic/microaerophilic atmosphere after cultivation for 24 or 72 h depending on the surface material. An overall higher adhesion ability was observed in arcobacters. A chi-squared test showed no association between the origin of the strains and biofilm activity (p > 0.05). Arcobacter-like species are able to form biofilms under microaerophilic and aerobic conditions; however, they prefer microaerophilic environments. Biofilm formation has already been demonstrated at refrigerator temperatures (5 °C). Arcobacters also showed higher biofilm formation ability at the temperature of 30 °C. This is in contrast to Campylobacter jejuni NP 2896, which showed higher biofilm formation ability at temperatures of 5–30 °C. Overall, the results demonstrated the biofilm formation ability of many strains, which poses a considerable risk to the food industry, medical practice, and human health. View Full-Text

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Posted in Biofilm, Campylobacter, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research

Research – Antimicrobial resistance, virulence , Antimicrobial resistance, virulence genes, and biofilm formation in Staphylococcus aureus strains isolated from meat and meat products

Posted on September 28, 2021 by | Leave a comment

Wiley Online

Staphylococcus aureus is an important food pathogen that has the ability to form biofilms. This pathogen has been implicated in foodborne outbreaks associated with the consumption of meat and meat products. Since the role of meat products as reservoirs of antimicrobial resistant S. aureus and biofilm formers has not been studied, this research was conducted to assess the incidence, antimicrobial resistance, and presence of biofilm-forming genes in S. aureus bacteria from meat and meat products. For this purpose, 440 samples of meat and meat products were randomly collected from supermarkets of Shahrekord city, Iran. S. aureus isolates were highlighted and identified through biochemical tests. All S. aureus isolates were profiled for susceptibility to 14 antibiotics and the corresponding resistance genes were searched. The quantification of biofilm formation followed by a screening of biofilm formation encoding genes was done. Of the 440 samples collected, 61 were found to contain S. aureus. The incidence of S. aureus among the beef meat (16/61) was the highest followed by its incidence in sausage (10/61) and lunch meat (9/61). At least one isolate of S. aureus carries one of the following resistance gene blaZ, mecA, tet K, linA, tetM, erm A, ermB, and aac A-D. High distribution of icaA, icaB, icaC, icaD, clfB, and clfA, biofilm formation genes and Enterotoxin encoding genes sea, seb, sec, and sed. The ability of biofilm production and the presence of virulence determinants in the genome of S. aureus can contribute to their pathogenicity. This research demonstrated the roles of meat and meat products as reservoirs of biofilm-forming and antimicrobial-resistant strains of S. aureus. This poses a food safety and public health problem. However, further work needs to be done to better understand the implication of icaABCD biofilm forming genes present in S. aureus from meat and meat products in their resistance.

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Posted in Biofilm, Enterotoxin, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research, Staphylococcus aureus

Research – Formation of multi-species biofilms and their resistance to disinfectants in food processing environments: A review

Posted on August 2, 2021 by | Leave a comment

Journal of Food Protection

In food processing environments, various microorganisms can adhere and aggregate on the surface of equipment, resulting in the formation of multi-species biofilms. Complex interactions among microorganisms may affect the formation of multi-species biofilms and their resistance to disinfectants, which are food safety and quality concerns. This paper reviews the various interactions among microorganisms in multi-species biofilms, including competitive, cooperative and neutral interactions. Then, the preliminary mechanisms underlying the formation of multi-species biofilms are discussed in relation to factors, such as quorum sensing (QS) signal molecules, extracellular polymeric substances (EPS) and biofilm-regulated genes. Finally, the resistance mechanisms of common contaminating microorganisms to disinfectants in food processing environments are also summarized. This review is expected to facilitate a better understanding of inter-species interactions, and provide some implications for the control of multi-species biofilms in food processing.

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Posted in Biofilm, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations

Research – Effect of Gaseous Ozone on Listeria monocytogenes Planktonic Cells and Biofilm: An In Vitro Study

Posted on July 4, 2021 by | Leave a comment

MDPI

Among food-borne pathogens, Listeria monocytogenes continues to pose concerns to food business operators due to its capacity to form biofilm in processing environments. Ozone may be an eco-friendly technology to control microbial contaminations, but data concerning its effect on Listeria monocytogenes biofilm are still limited. In this study, the effect of gaseous ozone at 50 ppm on planktonic cells and biofilm of reference and food-related Listeria monocytogenes strains was evaluated. Ozone caused a reduction in microbial loads of 3.7 ± 0.4 and 3.9 ± 0.4 Log10 CFU/mL after 10 and 30 min, respectively. A complete inactivation of planktonic cells after 6 h of treatment was observed. Biofilm inhibition and eradication treatments (50 ppm, 6 h) resulted in a significant decrease of the biofilm biomass for 59% of the strains tested, whilst a slight dampening of live cell loads in the biofilm state was observed. In conclusion, gaseous ozone is not sufficient to completely counteract Listeria monocytogenes biofilm, but it may be useful as an additional tool to contrast Listeria monocytogenes free-living cells and to improve the existing sanitization procedures in food processing environments. View Full-Text

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Posted in Biofilm, food contamination, food handler, Food Hazard, Food Hygiene, Food Inspections, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Pathogen, Food Safety, Food Testing, Listeria, Listeria monocytogenes, Research

Research – Identification of Microorganisms from Several Surfaces by MALDI-TOF MS: P. aeruginosa Is Leading in Biofilm Formation

Posted on May 9, 2021 by | Leave a comment

MDPI

New ecological trends and changes in consumer behavior are known to favor biofilm formation in household appliances, increasing the need for new antimicrobial materials and surfaces. Their development requires laboratory-cultivated biofilms, or biofilm model systems (BMS), which allow for accelerated growth and offer better understanding of the underlying formation mechanisms. Here, we identified bacterial strains in wildtype biofilms from a variety of materials from domestic appliances using matrix-assisted laser desorption/ionization-time of flight mass spectroscopy (MALDI-TOF-MS). Staphylococci and pseudomonads were identified by MALDI-TOF-MS as the main genera in the habitats and were analyzed for biofilm formation using various in vitro methods. Standard quantitative biofilm assays were combined with scanning electron microscopy (SEM) to characterize biofilm formation. While Pseudomonas putida, a published lead germ, was not identified in any of the collected samples, Pseudomonas aeruginosa was found to be the most dominant biofilm producer. Water-born Pseudomonads were dominantly found in compartments with water contact only, such as in detergent compartment and detergent enemata. Furthermore, materials in contact with the washing load are predominantly colonized with bacteria from the human. View Full-Text

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Posted in Biofilm, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Technology, Malditof, microbial contamination, Microbiological Risk Assessment, Microbiology, Pseudomonas, Research, Staphylococcus aureus, Staphylococcus epidermidis, Technology