Exploitation of the antibacterial, antibiofilm and antioxidant activities of Salvadora Persica (Miswak) extract

The Salvadora persica (S. persica) L. chewing stick, usually known as miswak, is still being employed as an oral hygiene agent for plaque and gingivitis prevention. This study aims to assess the antibacterial, antibiofilm, antioxidant, and phytochemical profile of S. persica extract. The S. persica was purchased from a local market, grinded and extracted with petroleum ether. The disk diffusion, microdilution, and micro-plate assays were performed to evaluate the antibacterial and antibiofilm activities of the prepared extract at different concentrations against β-lactam resistance Streptococcus species. Free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and stable radical cationic chromophore, 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) methods were used to determine their antioxidant activity. Chromatographic and spectrometric analyses were performed using gas chromatography-mass (GC-MS) spectrometry. The minimum inhibitory concentration (MIC) of S. persica extract against β-lactam resistance Streptococcus species ranged from 6.25 to 12.5 mg/mL. The maximum suppression of biofilm formation by S. persica extract was observed at MIC with a percentage of 68.66%, against Streptococcus oralis. The S. persica extract exhibited antioxidant activity with IC50 of 20 µg/mL and 35 µg/mL from DPPH and ABTS, respectively. The phytochemical characterization showed the presence of 22 compounds with major compounds; benzyl isothiocyanate (36.21%) and n-hexadecanoic acid (27.62%). The S. persica extract exhibited antibacterial activity against β-lactam resistant Streptococcus species, showing a promising natural alternative that could be a treatment option.