# Antibacterial and Anti-Inflammatory Potential of Mouthwash Composition Based on Natural Extracts
## 4 Discussion
As a natural extract mouthwash, it had been reported to have various antibacterial, antioxidant, anti-inflammatory, and antifungal properties with low toxicity and minimal side effects, although effective in reducing plaque and gingivitis [69]. To replace chemical compounds in mouthwash, various studies are being progressed on natural extracts and their effects in oral diseases, including anticancer effect in oral epithelial cell cancer [70], oral disease suppression effect of Galla Rhois extract [71], and oral mucosal wound healing effect of _Aucuba japonica_ extract [72]. A mouthwash that maintains an ideal oral environment has a selective antibacterial effect against bacteria that cause oral diseases and bad breath and has no toxicity to human body and oral tissue [73]. Therefore, our study observed the effect of natural extracts-based mouthwash on oral pathogenic bacteria/nonpathogenic bacteria. The targets were _S. constellatus_, _S. sanguinis_, _S. mutants_, _E. corrodens_, _F. nucleatum_, _S. sobrinus_, _A. actinomycetemcomitans_, _P. gingivalis_, _P. nigrescens_, and _P. intermedia_. To observe the safety of each mouthwash, the experiment targeted _S. salivarius_ and _L. salivarius_, which are beneficial bacteria in the oral cavity. As a result of measuring black/white threshold ratio in CSK (_S. sanguinis_, _F. nucleatum_, _P. nigrescens_), M1 (_S. constellatus_ (A), _S. constellatus_ (B)), M3 (_E. corrodens_), M5 (_P. intermedia_), GA (_A. actinomycetemcomitans_, _P. gingivalis_), and LIS (_S. mutans_, _S. sobrinus_), the extinction concentration was significant at about 99.9%, and PG, SG, M2, and M4 effects on oral microorganisms were observed to be insignificant. The paper disc assay results of PG, CSK, SG, and natural extracts mixture series on two types of beneficial bacteria in the oral cavity showed no growth inhibition. It was considered that it did not affect the beneficial bacterial in the oral cavity, and it was suggested that it could be used as a safe material for mouthwash. This is considered to be a result of not using an appropriate concentration for cell survival of PG, CSK and SG, unlike natural extracts mixture series, which were mixed with other natural extracts in various ratios. The comparison of before and after LPS treatment in the NO assay showed that each mouthwash suppressed NO concentration after inducing inflammation by LPS. However, the reason why M1 and M2 had lower NO inhibition than other mouthwash was considered to be due to the difference in mixing ratio of each natural extract. Mint, such as _Mentha piperita_, has been reported to have antibacterial and anti-inflammatory effects [73]. The natural extract mixtures, M1-M5, contained mint extract powder. The mint extract powder we used is a food additive made from 80% dextrin, 10% mint oil (oils, peppermint), and 10% gum Arabic, and serves as a supplement in the product. It was added to give palatability and a refreshing sensation to the oral cavity due to the unique fragrance and taste of mint. With the antibacterial effect, cell survival, and anti-inflammatory effect put together, the chemical compound mouthwash inhibited growth of all pathogenic/nonpathogenic oral bacteria, but natural extracts and natural extract mixtures inhibited pathogenic oral bacterial only. It is considered that CHX, CPC, benzetonium chloride, and fluoride, which are the components of chemical compound mouthwash, prevent the oral environment from being balanced [4] and also affect symbiotic bacteria. When cell viability was observed considering the oral environment, the results of natural extracts (PG, CSK, SG) were similar to those of chemical compound mouthwashes (GA, LIS), which confirmed that proper mixing of natural extracts induced high cell viability. As a similar tendency was observed when inflammation was induced, it was confirmed that an appropriate ratio of natural extracts maintains a healthy oral environment, which suggested the possibility of antibacterial and anti-inflammatory effects against pathogenic bacterial in the oral cavity.