An attempt to identify the anti-biofilm aptitude of <i>Barleria lupulina</i> Lindl. Leaf extract on clinical isolates of multidrug-resistant <i>Staphylococcus aureus</i>

<p><i>Staphylococcus aureus</i>, a gram-positive bacterium, which causes skin and soft tissue infections in hospital and community settings, is one of the leading threats in public health because of their proficiency to develop biofilms as an adaptive feature.</p> <p><i>Barleria lupulina</i> leaf extract (BLLE) has been investigated as potent anti-biofilm agent against multi-drug-resistant <i>S. aureus</i>.</p> <p>BLLE exerted anti-biofilm activity against <i>S. aureus</i> with MBIC and MBEC values ranging between 200–300 µg.mL⁻¹ and 400–500 µg.mL⁻¹, respectively.

Gene expression studies revealed that BLLE could substantially downregulate accessory gene regulator (agr) expressions, an important regulator of quorum sensing as well as biofilm signaling pathway. SEM studies revealed anti-biofilm activity caused by BLLE. In silico analyses indicated that 2, 6-diisopropyl naphthalene and butyl cyclohexyl phthalate, present in BLLE, could interact with the hydrophobic cleft in the DNA binding LytTR domain of AgrA pocket.