Effect of Trans-Cinnamaldehyde on preformed biofilm and biofilm formation of Escherichia coli isolated from urine specimens

Abstract

Abstract Introduction Bacteria in most environments exist as communities of sessile cells in a selfproduced polymeric matrix known as biofilms. Biofilms are responsible for more than 80% of infections, including urinary tract infections (UTI). UTI is the most common hospital acquired infection, caused mainly by Escherichia coli (E.coli). E. coli can readily form biofilm in such infections, specially in the presence of indwelling urinary catheter. It’s difficult to eradicate bacteria in biofilms, since they are shielded from the host defense mechanisms as phagocytes and antibodies, as well as antibiotics. Searching for alternative or adjuvant substances for prevention and eradication of biofilm associated infections are therefore urgently needed. Aim of the work Studying the efficacy of the trans-cinnamaldehyde (TC) for preventing E. coli biofilm formation. Materials and methods Thirty isolates of E.coli were obtained from urine samples. To test the effect of TC on E.coli biofilm formation and preformed biofilms, microtitre plates (MTP) were inoculated with the isolated E.coli and were treated with different concentrations of TC and incubated at 37° C. A colorimetric assay was used to assess biofilm inhibition and inactivation and optical densities (OD) were compared before and after adding different TC concentrations. Results The mean OD of the isolated E.coli biofilms was 1.3 and significantly decreased when mixed with TC different concentrations. TC had high activity in inhibition of preformed E.coli biofilms, where no biofilm was detected on MTP treated with 1.25% and 1.5% TC. Conclusion TC inhibited the biofilm forming ability of E.coli isolates could fully inactivate formed biofilms, suggesting its possibility to be used as an anti-biofilm agent or adjuvant in preventing and treating UTI caused by biofilm producing E.coli.