Preparation of a Herbal Mouthwash With Lemongrass and Mint-Mediated Zinc Oxide Nanoparticles and Evaluation of Its Antimicrobial and Cytotoxic Properties

Cureus. 2024 Feb 5;16(2):e53671. doi: 10.7759/cureus.53671. eCollection 2024 Feb.

Abstract

Introduction Nanotechnology holds considerable importance in biomedical and dental applications. Nanoparticles synthesized using green synthesis methods with herbal formulations offer various benefits to humans. Zinc oxide nanoparticles (ZnONPs), being semiconductors, exhibit potent antibacterial properties. Notably, treatments utilizing lemongrass and mint ensure potentially lower toxicity and antibacterial qualities for oral infections. The goal of the study is to prepare a mouthwash mediated by ZnONPs and assess its cytotoxic potential and antibacterial efficacy. Materials and methods A lemongrass and mint formulation was used in the synthesis of ZnONPs, and the mouthwash was prepared using the synthesized nanoparticles. The produced ZnONPs were tested for their antimicrobial activity using agar well diffusion technique against oral pathogens, and the ZnONPs-mediated mouthwash was evaluated for its cytotoxic effect using the brine shrimp lethality assay and compared to commercial mouthwash. Results The green-synthesized ZnONPs were initially confirmed using a UV-visible spectrophotometer and exhibited a maximum peak at 362 nm. The antimicrobial activity was tested for the synthesized ZnONPs against oral pathogens, which showed a maximum zone of inhibition of 22 mm in Enterococcus faecalis and 23 mm in Candida albicans, as estimated by the agar well diffusion technique. Additionally, ZnONPs-based herbal mouthwash demonstrated lower cytotoxicity than the commercial mouthwash in the brine shrimp lethality assay. Conclusion In the current study, lemongrass and mint-mediated ZnONPs demonstrated an effective antibacterial activity against E. faecalis and antifungal activity against C. albicans. Furthermore, the cytotoxic effect tested using the brine shrimp lethality assay for ZnONPs-mediated mouthwash demonstrated lower toxicity as compared to the commercial mouthwash. This suggests that the green-synthesized ZnONPs-based mouthwash could be used as an alternative to synthetic mouthwash.

Keywords: antimicrobial activity; cytotoxic effect; eco-friendly; herbal mouthwash; product development; zinc oxide nanoparticles.