Effects of Extracts from Medicinal Plants on Biofilm Formation by Escherichia ColiUrinary Tract Isolates

Autor: Vacheva, Anna, Mustafa, Byulent, Staneva, Jordanka, Marhova, Mariana, Kostadinova, Sonya, Todorova, Milka, Ivanova, Radka, Stoitsova, Stoyanka
Zdroj: Biotechnology & Biotechnological Equipment; January 2011, Vol. 25 Issue: Supplement 1 p92-97, 6p
Abstrakt: ABSTRACTBacteria grown as biofilm cause serious trouble in medical practice as a source of both contamination of indwelling medicinal devices, and nosocomial infections. Biofilm microorganisms develop antibiotic resistance more rapidly than plankton. For this reason, novel anti-biofilm strategies address the search of substances that may suppress biofilm growth of pathogens without killing the microorganisms themselves. This report presents the results of a search for plant substances corresponding to these requirements. Three strains of urinary clinical isolates of E. coli, two uropathogenic (UPEC) and one from asymptomatic bacteriuria (ABU), with pre-established biofilm proficiency were compared. Antibiotic resistance of the strains was determined by the disk-diffusion assay. Each of the UPEC strains was resistant to two antibiotics while the ABU strain was multiresistant. The antibacterial and antibiofilm effects of 14 extracts in different organic solvents from four medicinal plants were tested. The dried extracts were dissolved as stocks in ethanol. Disk diffusion assay with different amounts of the extracts showed no antibacterial activity against the selected strains. Biofilm growth was examined by the crystal violet assay after growth for 24 h in M63 medium alone or supplemented with 10 μg/ml from the dried extracts. All of the extracts modulated biofilm growth, and four had significant biofilm suppression effects on the UPEC strains while they stimulated the attached mode of growth of the ABU strain. Meanwhile, the extracts had no significant influence on the growth curves of the UPEC, but could delay the growth of the ABU strain. This implies that they may contain valuable substances for application directed against pathogenic biofilms.
Databáze: Supplemental Index