Abstract:

Macrophytes are known as a natural source of antibacterial and anti-biofilm agents in addition to their high nutritional value. Pistia stratiotes (Water lettuce/Water cabbage) is an aquatic plant species belonging to the Araceae family, and it is widely distributed in shallow areas of streams, lakes, and swamps, and it is possible to produce in open aquariums and garden ponds. Studies are showing that Pistia stratiotes has antioxidant, antimicrobial, antiallergic, and anticarcinogenic properties. In studies conducted with extracts of its roots and leaves with substances such as methanol, ethanol, water, and ether, it has been shown that it has high phenolic and flavonoid content and antioxidant activity such as free radical scavenging and metal chelating. In our research, 500 µg/ml concentration of ethanol extracts of the roots and leaves of Pistia stratiotes, which was determined to have antioxidant and antimicrobial effects in previous studies, was used. Anti-biofilm effect was studied on 5 Staphylococcus and 17 Enterococcus isolates, which were determined to produce biofilm, and on Staphylococcus aureus 29213 and Enterococcus faecalis 29212 as positive controls. Biofilm production and anti-biofilm tests were performed on a 96-well microplate by staining with crystal violet. According to the test results, the leaf extract of Pistia stratiotes, Staphylococcus aureus ATCC 29213 (%inhibition±SEM: 96±0.06 µg/ml), Enterococcus faecalis 29212 (%inhibition ±SEM: 88.5±0.01 µg/ ml) and 4 Staphylococcus and 5 Enterococcus isolates showed significant anti-biofilm properties (p˂0.05) compared to the control. The root extract, on the other hand, showed a remarkable inhibition (%inhibition±SEM: 86.8±0.02 µg/ml) (p˂0.05) in a single Staphylococcus isolate compared to the control.