Inhibitory Effect of Nepeta deflersiana on Climax Bacterial Community Isolated from the Oral Plaque of Patients with Periodontal Disease

Abstract

Background: The red-complex bacteria are one of the most significant complexes found simultaneously in subgingival plaque next to the periodontal pocket. The current antibacterial treatment is not adequate, and multidrug resistance to it is developing. Henceforth, the antibacterial effect of the ethanolic extract of Nepeta deflersiana was put to test against red-complex bacteria in patients with chronic periodontitis.

Methods: Well diffusion and micro broth dilution procedure by Alamar blue were applied to assess the zone of inhibition (ZOI), the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC). Anti-virulence efficacies of the plant extract that comprise of adherence and formation of biofilms were examined by the process of adherence and biofilm production assay.

Results: The crude extract of Nepeta deflersiana exhibited significant inhibitory outcome against periodontopathic bacteria with noteworthy MIC (0.78-3.12 mg/mL), inhibitory zone (12-20 mm), as well as MBC (3.12-12.50 mg/mL). The N. deflersiana extract inhibited bacterial adhesion ranging from 41% to 52%, 53% to 66%, and 60% to 79% at the given MIC × 0.5, MIC × 1, and MIC × 2 in succession. Substantial suppression was also developed in the biofilm production of the investigated periodontopathic strains following exposure to numerous concentrations of N. deflersianan extract for a period of 24 and 48 h.

Conclusion: These outcomes divulge a new concept that N. deflersiana extract can be utilized to manufacture valuable antibacterial compounds to treat chronic and acute periodontitis. This identifies N. deflersiana as an essential natural source for future drug development.

Keywords: N. deflersiana; antibacterial activity; biofilm; periodontal disease; red-complex bacteria.

Figure 1

Effect of ethanolic extract of N. deflersiana against periodontal bacteria. (A) Zone of inhibition formed by N. deflersiana extract against P. gingivalis, T. forsythia, and T. denticola. (B,C) MIC and MBC values of N. deflersiana extract against P. gingivalis, T. forsythia, and T. denticola.

Figure 2

N. deflersiana extract reduces bacterial adhesion. Adhesion assay based on Alamar blue was employed to assess the efficacy of N. deflersiana on T. forsythia, P. gingivalis, and T. denticola adherence. Each bacterial strain were treated with MIC × 0.5, MIC × 1 and MIC × 2 values of the plant extract at 37 °C for 6 h. Control bars specify each untreated bacterial strain, revealed as 0% inhibition. The data was conferred from three independent investigations using means ± SD *** p < 0.0001.

Figure 3

N. deflersiana extract diminishes biofilm formation. P. gingivalis, T. forsythia, and T. denticola were incubated with MIC × 0.5, MIC × 1, and MIC × 2 values of N. deflersiana extract in biofilm-producing environments for 24 and 48 h. Control bars specify each untreated bacterial strain, revealed as 0% inhibition. The data is conferred from three independent investigations using means ± SD *** p < 0.0001.

Figure 4

Effect of N. deflersiana on bacterial growth kinetics. Illustrative bacterial strains of (A) P. gingivalis, (B) T. denticola, and (C) T. forsythia were treated with different concentrations (MIC × 0.5, MIC × 1 and MIC × 2) of ethanolic extract of N. deflersiana. Untreated bacterial growth cycle was considered as growth control. The absorbance was measured at 610 nm at five-time intervals of 2 h. The data was conferred from three independent investigations using means ± SD (p < 0.0001).