Antibacterial Activity and Phytochemical Profiling of Pistacia lentiscus L. Leaf Extract Against Methicillin-Resistant and Susceptible Staphylococcus aureus
Abstract
The discovery of substitute antibacterial drugs derived from medicinal plants has accelerated due to the rising incidence of antimicrobial resistance. Pistacia lentiscus L. has a variety of bioactive phenolic and flavonoid chemicals and has long been used as a medicinal plant. Nevertheless, little is known about the relationship between its phytochemical composition and its antibacterial effectiveness against resistant Staphylococcus aureus. The purpose of this study was to assess the antibacterial activity of an 80% ethanolic leaf extract of P. lentiscus against S. aureus and methicillin-resistant Staphylococcus aureus (MRSA), compare its activity with specific antibiotics, and use HPLC to identify its phenolic and flavonoid constituents. P. lentiscus leaves were collected from Al-Jabal Al-Akhdar, Libya, and extracted with 80% ethanol via cold maceration. The well diffusion method and minimum inhibitory concentration (MIC) tests were used to evaluate the antibacterial activity. The activity was compared with imipenem, ciprofloxacin, vancomycin, and amoxicillin/clavulanate. HPLC was used to identify and quantify phenolic and flavonoid chemicals. The extract exhibited antibacterial activity against both isolates, resulting in inhibition zones of 14.0 ± 1.4 mm against S. aureus and 20.0 ± 0 mm against MRSA. The corresponding MICs were 1.562 and 3.125 mg/mL. Seven flavonoids and seven phenolic compounds were found; the most common flavonoids were rutin (18.50 μg/ml) and luteolin (17.36 μg/ml), while the main phenolic compounds were ferulic acid (12.95 μg/ml), p-coumaric acid (12.68 μg/ml), and caffeic acid (12.52 μg/ml). The 80% ethanolic leaf extract of P. lentiscus contained a variety of phenolic and flavonoid components and showed quantifiable antibacterial activity against MRSA and S. aureus. These results encourage more research on P. lentiscus as a possible source of antimicrobial chemicals.