Piperine Exhibits Promising Antibiofilm Activity Against Staphylococcus Aureus by Accumulating Reactive Oxygen Species (ROS)

Biofilm, an aggregated form of microbial existence has been a major area of concern in the healthcare units. These sessile microbes not only protect themselves from the host immune system but also exhibit high resistance against several antimicrobials. One such widely reported Gram-positive pathogen is Staphylococcus aureus. This human commensal is known to cause severe harmful diseases like bacteremia, sepsis, pneumonia, etc. Thus, strategies need to be undertaken to deal with such biofilm challenges. In this respect, we aimed to inhibit microbial biofilm formation of Staphylococcus aureus under the influence of a natural compound, piperine. Our study revealed that the higher concentrations of piperine exhibited considerable antimicrobial activity against Staphylococcus aureus. Hence, lower concentrations of piperine were tested to examine its antibiofilm activity. Several experiments like crystal violet (CV) assay, total biofilm protein assay, and fluorescence microscopy observation established that lower concentrations (8 µg/mL and 16 µg/mL) of piperine showed efficient antibiofilm activity against Staphylococcus aureus. It was also noticed that the lower concentrations of piperine did not compromise the microbial growth of Staphylococcus aureus while exhibiting antibiofilm activity. In this connection, we also noticed that the lower concentrations of piperine showed a considerable reduction in microbial metabolic activity. Furthermore, we observed that the compound was found to accumulate reactive oxygen species in the bacterial cells that could play an important role in the inhibition of biofilm formation. Thus, piperine could be considered as a potential antibiofilm agent against the biofilm formation caused by Staphylococcus aureus.