Pseudomonas aeruginosa (P. aeruginosa), the most pathogenic species among the pseudomonas species, is a bacterium that causes opportunistic infections resulting in significant damage to host tissues. P. aeruginosa, which is resistant to antibiotics, also causes fatal infection in human and animals. Infections caused by P. aeruginosa are difficult to treat due to its rapid proliferation in the environment and its ability to form biofilms that confer resistance to antibiotics. One of the main virulence factors of P. aeruginosa is its direct damage to host tissues, which disrupts the host’s defense mechanisms. P. aeruginosa is a food-borne pathogen often detected in various food groups such as meat, milk, fruit, vegetables, and water. In recent years, there has been a noticeable rise in food-borne contamination with P. aeruginosa. New measures are urgently needed in the treatment of patients with infections due to this agent, since P. aeruginosa can develop resistance to most antibacterials. In this review, general information about P. aeruginosa, which has gained importance for public health, will be given.

It is commonly well-known that biofilms are the predominant mode of bacterial growth, reflected in the clinic observations, where approximately 80% of all bacterial infections are related to biofilms. Bacteria in biofilms are well protected against environmental stresses, antibiotics, disinfectants and the host’s immune system and are usually extremely difficult to eradicate. Due to common problems caused by biofilms, alternative anti-biofilm strategies must be developed. Enterococcus strains are able to form complex surface-associated communities (biofilms), which contribute to its resistance and persistence in both host and non-host environments, and are especially important in food processing and clinical environments. Enterococcus biofilms showed increased antimicrobial resistance to the most of antibiotics as compared to the planktonic bacteria, which make them difficult to combat. There is an increasing evidence that biofilms are often associated with infectious diseases. Novel anti-biofilm strategies must be designed to include natural bio products instead of common antibiotics. Mushrooms are a nutritionally functional foods and a source of pharmaceuticals having functions such as antitumor, immunomodulating, antioxidant, cardiovascular, anti-hypercholesterolemia, antiviral, antibacterial, anti-parasitic, antifungal, detoxification, hepatoprotective, and antidiabetic. In addition, they have a notable activity against biofilms. In this study, the antimicrobial and anti-biofilm activities of some medicinal and edible mushrooms, namely Morchella angusticeps Peck, Ganoderma lucidum (Curtis) P. Karst., Cerioporus squamosus (Huds.) Quél., Trametes versicolor (L.) Lloyd and Lentinula edodes (Berk.) Singer were screened against multi drug resistant Enterococcus strains. As a result, it was observed that these mushrooms have notable potency to develop alternative medicines to struggle infectious diseases and biofilms.

A biofilm is a complex matrix formed by microorganisms that includes exopolysaccharides, proteins, extracellular DNA, various enzymes, and the microorganisms themselves. Biofilm cell is a more stable form of microorganism than planktonic cell. Microbial cells attach themselves to the surface after certain signals or changes, colonize to create a more favorable environment for their growth and viability, and secrete exopolysaccharide. This component is the basic matrix of biofilm. The diversity of exopolysaccharides within biofilms varies significantly depending on their specific composition, contributing uniquely to the characteristics of biofilms. This diversity in biofilms underscores the need for targeted control strategies. Biofilms can be beneficial or harmful depending on the situation and where they develop. Accordingly, microbial biofilms have dual effects on health. Biofilms can have both harmful effects on health, such as contributing to antibiotic resistance and persistent infections, while biofilms formed by beneficial microorganisms play a crucial role in enhancing food functionality. Moreover, the formation of biofilm in certain foods can contribute to the enhancement of the product matrix, particularly by improving its texture. In this review, the structures of these biofilms, their basic components, their possible safety concerns, and health benefits are discussed. Moreover, this review deals with biofilm producing bacteria in foods and assesses the prevention strategies for biofilm formation within the food industry.