The antibacterial effect of Plectranthus scutellarioides (L.) R.Br. leaves extract against bacteria associated with peri-implantitis

Nor Amiyah Bismelah; Rohana Ahmad; Zethy Hanum Mohamed Kassim; Nor Hadiani Ismail; Nurulfazlina Edayah Rasol

doi:10.1016/j.jtcme.2022.07.002

The antibacterial effect of Plectranthus scutellarioides (L.) R.Br. leaves extract against bacteria associated with peri-implantitis

J Tradit Complement Med. 2022 Aug 3;12(6):556-566. doi: 10.1016/j.jtcme.2022.07.002. eCollection 2022 Nov.

Authors

Nor Amiyah Bismelah¹, Rohana Ahmad^{1

2}, Zethy Hanum Mohamed Kassim¹, Nor Hadiani Ismail³, Nurulfazlina Edayah Rasol³

Affiliations

¹ Centre of Restorative Dentistry Studies, Faculty of Dentistry, Universiti Teknologi MARA Sg. Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia.
² Integrative Pharmacogenomics Institute (iPromise), Universiti Teknologi MARA, Puncak Alam Campus, 42300, Bandar Puncak Alam, Selangor, Malaysia.
³ Atta-ur-Rahman Institute for Natural Product Discovery (AuRins) Universiti Teknologi MARA, Puncak Alam Campus, 43600 Bandar Puncak Alam, Selangor, Malaysia.

Abstract

Background and aim: The present study investigates Plectranthus scutellarioides (L.) R.Br. as potential antibacterial oral rinse against bacteria associated with peri-implantitis to prevent the initial infection as well as disease progression.

Experimental procedure: Phytochemical screening was done on P. scutellarioides lyophilized extract to identify the presence of chemical constituent by using mass-based identification. The extract was screened for its antibacterial activity against 4 Gram-positive aerobes (early colonizer) and 5 Gram-negative facultative anaerobes as well as obligate anaerobes (late colonizer) using disc diffusion method. The extract was tested for minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), its cytotoxicity effects on human gingival fibroblast cell (HnGF) as well as bacteria morphological changes by scanning electron microscopy (SEM).

Results and conclusion: Four flavonoid compounds were identified namely quercetin-3-glucoside, quercitrin, quercetin 3-(6″-acetylglucoside) and quercetin 3-O-acetyl-rhamnoside. The sensitivity test revealed that P. scutellarioides extract was effective against all the bacteria tested. MIC concentrations for the Gram-positive aerobes were in the range of 1.56-12.50 mg/mL, and the MBC concentrations were within 3.13-12.50 mg/mL. For Gram-negative obligate anaerobes, the MIC concentration were within 3.13-12.50 mg/mL and MBC within 6.25-200.00 mg/mL. The ethanolic extract did not have any cytotoxic effect on HnGF cells at the tested concentrations. SEM images showed bacterial cell wall disruption for all the bacteria tested. The results showed that P. scutellarioides extract exerts its antibacterial property by disrupting the cell wall of all the bacteria tested. Hence, P. scutellarioides may benefit from further investigations on its safety for oral use as an adjunctive treatment for peri-implantitis.

Keywords: Antibacterial activity; Cell wall disruption; Cytotoxicity; Peri-implantitis; Plectranthus scutellarioides (L.) R.Br..