OF THE THESIS CONTROLLED-RELEASE ANTIMICROBIALS FOR PREVENTING BIOFILM FORMATION IN FOOD AND MEDICAL APPLICATIONS By LINDA E. ROSENBERG Thesis Director: Dr. Michael Chikindas Bacterial biofilms generally are more resistant to stresses as compared to free planktonic cells. Therefore, the discovery of antimicrobial stress factors that have strong inhibitory effects on bacterial biofilm formation ...

Biofilms are defined as aggregation of single cell microorganisms and associated with over 80% of all the microbial infections. Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen capable of leading to various infections in immunocompromised people. Recent studies showed that norspermidine, a kind of polyamine, prevented and disrupted biofilm formation by some Gram-negative bacteri...

Stenotrophomonas maltophilia is an opportunistic pathogen that causes respiratory and urinary tract infections, as well as wound infections in immunocompromised patients. This pathogen is difficult to treat due to increased resistance to many antimicrobial agents. We investigated the in vitro biofilm formation of S. maltophilia, including effects of fluoroquinolones (FQs) and azithromycin on bi...

Background: Klebsiella pneumoniae is one of the most important bacteria that cause nosocomial infections. This opportunistic pathogen has a high potential for antibiotic resistance and can generate a thick layer of biofilm. Nowadays, antibiotic resistant strains are emerging and widely spreading worldwide. Thus, it is necessary to combat drug-resistant strains through the use of novel drugs (su...

INTRODUCTION Escherichia coli O157:H7 possesses one chromosomal and two prophagic sodC genes encoding for Cu,Zn superoxide dismutases. We evaluated the contribution of sodC genes in biofilm formation and its resistance to hydrogen peroxide. METHODS The biofilm of sodC deletion mutants has been studied, in presence or absence of hydrogen peroxide, by crystal violet in 96-well plates and Scanni...

Stenotrophomonas maltophilia, an opportunistic pathogen usually connected with healthcare-associated infections, is an environmental bacterium. Intrinsic resistance to multiple antibiotics, with different virulence determinants in the last decade classified this bacterium in the group of global multiple drug resistant (MDR) organism. S. maltophilia clinical isolates, were collected from tertiar...

Klebsiella pneumoniae, an important opportunistic pathogen, exists as a biofilm in persistent infections and in-dwelling medical devices. With the objective of identifying natural compounds inhibiting biofilm formation in K. pneumoniae, 35 clinical isolates were screened,out of which 7 strong biofilm producers were identified. Six natural compounds were tested for their inhibitory effects on ba...