TDK conference 2019

Biofilms, the invisible companions of our daily lives can be found anywhere in our surroundings. Biofilm cultures are made up of microorganisms, which are able to attach to both biotic and abiotic surfaces, causing infections. They are responsible for some chronic illnesses, for instance, urinary tract infections, otitis media, and gingivitis. The extracellular polymeric substances prove them increased resistance to antibiotics, so struggle against these biofilm producing bacteria is a continous challenge. Studies have demonstrated that these systems have high antibiotic tolerance, and are more protected from environmental factors, than their planktonic forms. The aim of my experiment to study inhibition effect of plant extracts on the growth of the bacterial biofilm. The examined plants, all have already well documented medical effects (Trapa natans, Rosmarinus officinalis, Camellia sinensis, Mentha x piperita). I studied two different methods for extraction of plants (Liquid-solid, Soxhlet-extraction). The antibiofilm activity of the extracts was tested on Staphylococcus pseudintermedius and Pseudomonas aeruginosa bacteria cultures. Five different concentrations of the extracts were examined using a double dilution method. The bacteria cultures were dyed with crystal violet solution and analyzed by spectrophotometer to determine the biofilm quantity. Using a control, I have established the effective concetration of plant extracts against the studied bacteria. The extract of water chestnut (Trapa natans) proved effective againts the biofilm of the studied bacteria. The composition of the extracts was examined by TLC and a couple of bioactive compounds with biofilm activity were successfully detected. The conditions (eluents, stains for developing) of thin layer chromatography were optimised and the compounds were identified by retention factor (Rf) values.