Category Archives: Antibacterial

Research – The Role of Biofilms in the Pathogenesis of Animal Bacterial Infections



Biofilms are bacterial aggregates embedded in a self-produced, protective matrix. The biofilm lifestyle offers resilience to external threats such as the immune system, antimicrobials, and other treatments. It is therefore not surprising that biofilms have been observed to be present in a number of bacterial infections. This review describes biofilm-associated bacterial infections in most body systems of husbandry animals, including fish, as well as in sport and companion animals. The biofilms have been observed in the auditory, cardiovascular, central nervous, digestive, integumentary, reproductive, respiratory, urinary, and visual system. A number of potential roles that biofilms can play in disease pathogenesis are also described. Biofilms can induce or regulate local inflammation. For some bacterial species, biofilms appear to facilitate intracellular invasion. Biofilms can also obstruct the healing process by acting as a physical barrier. The long-term protection of bacteria in biofilms can contribute to chronic subclinical infections, Furthermore, a biofilm already present may be used by other pathogens to avoid elimination by the immune system. This review shows the importance of acknowledging the role of biofilms in animal bacterial infections, as this influences both diagnostic procedures and treatment.

Research – Recent insights into green antimicrobial packaging towards food safety reinforcement: A review

Wiley Online


Food packaging is widely used method of food preservation around the world. It is an element that enhances the quality and food product safety. The primary function of packaging is to protect food from contamination, undesirable chemical reactions and to provide physical protection. Food spoilage caused by food-borne pathogens and microbes is increasing tremendously posing an enormous threat. In the field of food packaging, new biodegradable and natural antimicrobial agents from plants and animals are gaining popularity. Recent foodborne outbreaks have prompted more creative and safe ways to initiate efficient packaging systems in food industries. However, as consumer demand for natural food ingredients has grown as a result of increasing safety and availability, natural substances are thought to be safer. Antimicrobial packaging that incorporates natural antimicrobials is thus a viable active packaging innovation. One possibility for increasing the safety and quality of foods while prolonging their shelf life is to employ natural antibacterial packaging. This article focuses on environmentally friendly bio-based polymers that can be utilized in food packaging to enhance mechanical strength, gas permeability, and water resistance, among other features. It also includes useful information about natural antimicrobial agents found in fruits and vegetables, as well as animal by-products, their properties, safety laws, and uses aimed at improving and increasing food quality and safety.

Research – Antimicrobial Effect of Moringa oleifera Leaves Extract on Foodborne Pathogens in Ground Beef



Consumers nowadays are becoming more aware of the importance of using only meat products containing safe and natural additives. Hence, using natural food additives for extending the shelf life of meat along with delaying microbial growth has become an urgent issue. Given the increasingly popular view of Moringa oleifera leaves as a traditional remedy and also the scarcity of published data concerning its antimicrobial effect against foodborne pathogens in meat and meat products, we designed the present study to investigate the antimicrobial effect of Moringa oleifera leaves aqueous extract (0.5%, 1%, and 2%) on ground beef during refrigerated storage at 4 °C for 18 days. MLE revealed potent antimicrobial properties against spoilage bacteria, such as aerobic plate count and Enterobacteriaceae count. MLE 2% showed a significant (p < 0.01) reduction in the counts of E. coli O157:H7, Salmonella enterica serovar Typhimurium, and Staphylococcus aureus artificially inoculated to ground beef by 6.54, 5.35, and 5.40 log10 CFU/g, respectively, compared to control, by the 18th day of storage. Moringa leaves extract (MLE) had no adverse effect on the overall acceptability and other sensory attributes; moreover, it induced a slight improvement in the tenderness and juiciness of treated ground beef, compared to the control. Therefore, MLE can be used as a healthy, natural, and safe preservative to increase meat products’ safety, quality, and shelf stability during cold storage. A promising approach for using natural food additives rather than chemical preservatives could begin new frontiers in the food industry, as they are more safe and do not constitute health risks to consumers.

Research – Antibacterial and Anti-Biofilm Properties of Diopside Powder Loaded with Lysostaphin



Background: Diopside-based ceramic is a perspective biocompatible material with numerous potential applications in the field of bone prosthetics. Implantable devices and materials are often prone to colonization and biofilm formation by pathogens such as Staphylococcus aureus, which in the case of bone grafting leads to osteomyelitis, an infectious bone and bone marrow injury. To lower the risk of bacterial colonization, implanted materials can be impregnated with antimicrobials. In this work, we loaded the antibacterial enzyme lysostaphin on diopside powder and studied the antibacterial and antibiofilm properties of such material to probe the utility of this approach for diopside-based prosthetic materials. Methods: Diopside powder was synthesized by the solid-state method, lysostaphin was loaded on diopside by adsorption, the release of lysostaphin from diopside was monitored by ELISA, and antibacterial and anti-biofilm activity was assessed by standard microbiological procedures. Results and conclusions: Lysostaphin released from diopside powder showed high antibacterial activity against planktonic bacteria and effectively destroyed 24-h staphylococcal biofilms. Diopside-based materials possess a potential for the development of antibacterial bone grafting materials.

Research – Fighting Foodborne Pathogens with Natural Antimicrobials

Mirage News

The food industry has now started exploring natural alternatives for preserving food to reduce the dependency on chemical preservatives, some of which are linked to obesity and metabolic syndrome. Specifically, natural antimicrobials produced by plants and microorganisms like bacteria and fungi can kill food-borne pathogens like Salmonella Typhimurium, Escherichia coliListeria monocytogenes and Clostridium botulinum and also food spoilage bacteria like Brochothrix thermosphactaLactobacillus spp., Bacillus spp. and Weissella spp., among others. Foodborne pathogens and spoilage microbes pose a serious health concern for consumers and destroy the appearance, texture and sensory characteristics of the food, affecting the food industry and consumers alike.

Research – Occurrence and Multidrug Resistance of Campylobacter in Chicken Meat from Different Production Systems


Campylobacter kswfoodworld

Campylobacter is the leading bacterial cause of diarrheal disease worldwide and poultry remains the primary vehicle of its transmission to humans. Due to the rapid increase in antibiotic resistance among Campylobacter strains, the World Health Organization (WHO) added Campylobacter fluoroquinolone resistance to the WHO list of antibiotic-resistant “priority pathogens”. This study aimed to investigate the occurrence and antibiotic resistance of Campylobacter spp. in meat samples from chickens reared in different production systems: (a) conventional, (b) free-range and (c) backyard farming. Campylobacter spp. was detected in all samples from conventionally reared and free-range broilers and in 72.7% of backyard chicken samples. Levels of contamination were on average 2.7 × 103 colony forming units (CFU)/g, 4.4 × 102 CFU/g and 4.2 × 104 CFU/g in conventionally reared, free-range and backyard chickens, respectively. Campylobacter jejuni and Campylobacter coli were the only species isolated. Distribution of these species does not seem to be affected by the production system. The overall prevalence of Campylobacter isolates exhibiting resistance to at least one antimicrobial was 98.4%. All the C. coli isolates showed resistance to ciprofloxacin and to nalidixic acid, and 79.5 and 97.4% to ampicillin and tetracycline, respectively. In total, 96.2% of C. jejuni isolates displayed a resistant phenotype to ciprofloxacin and to nalidixic acid, and 92.3% to ampicillin and tetracycline. Of the 130 Campylobacter isolates tested, 97.7% were classified as multidrug resistant (MDR).

Research – Preservation of cut fruit and use of a technological adjuvant for washing certain vegetables


The Spanish Agency for Food Safety and Nutrition has published two new reports from its Scientific Committee:

  • Report on the storage conditions of fruit cut in half in retail establishments.
  • Report on the safety of the use of an aqueous solution of sodium lauryl ether sulfate as a processing aid for washing apples, peaches, bananas, tomatoes, peppers and citrus in processing plants .      

Report on the storage conditions of fruit cut in half in retail establishments

The AESAN Scientific Committee has assessed whether it is possible to keep melon, watermelon, pineapple and papaya cut in half at room temperature in retail establishments for a limited time, ensuring consumer safety.

The Scientific Committee has concluded that, on the basis of the information

  • Storage at room temperature of melon, watermelon, papaya and pineapple cut in half can pose a health risk as the physicochemical conditions (pH, water activity, total soluble solids, nutrient availability, etc.) are compatible with growth. of foodborne pathogens, such as Salmonella , E. coli verotoxigenic or L. monocytogenes .
  • In order to make the storage conditions of melon, watermelon, papaya and pineapple cut in half more flexible, temperatures below 25 ºC for a time of less than 3 may be allowed, as they do not pose a significant microbiological risk. hours in a place sufficiently ventilated and preserved from sunlight, followed by continuous refrigerated storage at temperatures below 5 ºC.
  • To minimize the health risk that these practices may pose, it is recommended to discard for cutting fruits with an excessive degree of ripeness, or that have wounds or cracks on their surface, as they can be a source of contamination.

Report on the safety of the use of an aqueous solution of sodium lauryl ether sulfate as a processing aid for washing apples, peaches, bananas, tomatoes, peppers and citrus in processing plants

The AESAN Scientific Committee has evaluated the safety of using an aqueous solution of sodium lauryl ether sulfate (27%) as a technological aid for washing apples, peaches, bananas, tomatoes, peppers and citrus in processing plants. request of a company request.

Sodium lauryl ether sulfate (LESS) is not authorized for human consumption.

As the presence of residues in the final products (fruits and vegetables) after the use of this aqueous solution cannot be ruled out, the technology adjuvant is classified as an unauthorized substance in human food whose Admissible Daily Intake (ADI) is not established and whose use may lead to the presence of technically unavoidable waste.

The Scientific Committee concludes that, based on the information provided by the applicant and taking into account the proposed composition and conditions of use, the use of the technology adjuvant does not imply a risk to the health of the consumer.

The conclusions of this report refer exclusively to the solution under evaluation as a technological aid in the proposed conditions of use and its composition, and may not be extended to formulations or conditions other than those evaluated, including joint use with other substances.

This evaluation does not imply an authorization for use or affect uses other than use as a technological aid in the process of washing apples, peaches, bananas, tomatoes, peppers and citrus in the processing plants. This use involves a final rinsing with drinking water, following the application of the washing water with the technological adjuvant, so that the possible residues in the fruits and vegetables are eliminated.

Click to access FRUTAS_CORTADAS.pdf


Research – Surveillance of Antimicrobial Resistance (AMR) in E. coli and Campylobacter from retail turkey meat and E. coli from retail lamb in 2020/21-FS102109



This report presents results of the surveillance of antimicrobial resistance (AMR) in specific bacteria, i.e., Campylobacter and Escherichia coli (E.coli)from lamb and turkey meats on retail sale in the UK between October 2020 and February 2021.
The aim was to test by culture approximately 200 samples each of lamb and turkey meat for E.coli, and also to test the turkey samples for Campylobacter. The FSA requested testing of lamb and turkey meat as the majority of AMR surveys on UK retail meats have focused on beef, chicken and pork.
As such there is an evidence gap for AMR in lamb and turkey meat. E. coli is a normal inhabitant of the mammalian and avian gut and most isolates do not cause observable clinical disease in healthy animals and humans. Therefore, E.coli isolates can be useful “indicators” of AMR in gut bacteria. Campylobacter is frequently present in the gut of healthy poultry, and thermophilic species (Campylobacter jejuni and Campylobacter coli) typically cause food poisoning in humans.
The monitoring of lamb and turkey meat for AMR is not mandatory as part of the European Directive 2003/99/EC, but the methodology used in this survey was broadly based on the current EU methodologies for the testing of retail beef, chicken and pork. These methodologies involve culture of E. coli on selective agar media containing the antimicrobial drug cefotaxime. Growth of E. coli on such plates indicate resistance to third generation cephalosporin antimicrobial drugs, including extended-spectrum beta lactamase (ESBL) and Amp C type resistance. Such isolates should be further tested for susceptibility to a panel of antimicrobials by determining minimum inhibitory concentration (MIC) values using a broth dilution method based on EN ISO 20776-1:2006.As recommended by the EU, additional selective cultures were performed on samples to isolate any E.coli resistant to carbapenem antimicrobials. Carbapenems are termed ‘last resort’ drugs, used to treat severe infections when other treatment options are ineffective because of multiple resistances in the target Gram negative bacteria.

6At the request of the FSA (non-harmonised testing outside the remit of Decision 2013/652/EU) further screening was performed for E.coli strains resistant to colistin (another ‘last resort’ human antimicrobial drug) and those specifically producing ESBL resistance enzymes. Colistin-resistant strains may harbour mcr resistance genes, which are located on plasmids that can transfer between bacteria.

Research – Strategies for Biocontrol of Listeria monocytogenes Using Lactic Acid Bacteria and Their Metabolites in Ready-To-Eat Meat- and Dairy-Ripened Products


Listeria monocytogenes is one of the most important foodborne pathogens. This microorganism is a serious concern in the ready-to-eat (RTE) meat and dairy-ripened products industries. The use of lactic acid bacteria (LAB)-producing anti-L. monocytogenes peptides (bacteriocins) and/or lactic acid and/or other antimicrobial system could be a promising tool to control this pathogen in RTE meat and dairy products. This review provides an up to date about the strategies of use of LAB and their metabolites in RTE meat products and dairy foods by selecting the most appropriate strains, by analysing the mechanism by which they inhibit L. monocytogenes and methods of effective application of LAB, and their metabolites in these kinds of products to control this pathogen throughout the processing and storage. The selection of LAB with anti-L. monocytogenes activity allows to dispose of effective strains in meat and dairy-ripened products, achieving reductions form 2–5 logarithmic cycles of this pathogen throughout the ripening process. The combination of selected LAB strains with antimicrobial compounds, such as acid/sodium lactate and other strategies, as the active packaging could be the next future innovation for eliminating risk of L. monocytogenes in meat and dairy-ripened products.

Research – Antibacterial Properties of TMA against Escherichia coli and Effect of Temperature and Storage Duration on TMA Content, Lysozyme Activity and Content in Eggs


Studies on trimethylamine (TMA) in egg yolk have focused on how it impacts the flavor of eggs, but there has been little focus on its other functions. We designed an in vitro antibacterial test of TMA according to TMA concentrations that covered the TMA contents typically found in egg yolk. The change in TMA content in yolk was analyzed at different storage temperatures and for different storage durations. The known antibacterial components of eggs, including the cuticle quality of the eggshell and the lysozyme activity and content in egg white, were also assessed. The total bacterial count (TBC) of different parts of eggs were detected. The results showed that the inhibitory effect of TMA on Escherichia coli (E. coli) growth increased with increasing TMA concentration, and the yolk TMA content significantly increased with storage duration (< 0.05). The cuticle quality and lysozyme content and activity significantly decreased with storage time and increasing temperature, accompanied by a significant increase in the TBC on the eggshell surface and in the egg white (< 0.05). This work reveals a new role for trace TMA in yolks because it reduces the risk of bacterial colonization, especially when the antibacterial function of eggs is gradually weakened during storage.