Antibacterial efficacy and molecular docking analysis of Zingiber offinale and Allium sativum against Fusobacterium nucleatum - An in vitro study

Abstract

Background: Fusobacterium nucleatum is a keystone organism associated with secondary endodontic infections. Numerous virulence traits are displayed by this bacterium, which coaggregates with other species and is speculated to function as a "supportive bridge" between primary and secondary invaders in the formation of root canal biofilms.

Aim and objectives: To evaluate the antimicrobial efficacy of Zingiber officinale (ZO) (Ginger) and Allium sativum (AS) (Garlic) against F. nucleatum.

Materials and methods: Extracts were prepared by powdering freshly dried ginger and garlic, and the extraction process was done using a Soxhlet apparatus. Broth microdilution assay and microtiter plate assay of the ginger and garlic extracts were done for evaluating antibacterial activity. Gas chromatography-mass spectrometry analysis was done to identify phytochemical constituents present in extracts responsible for antibacterial action. Molecular docking was done to evaluate the interaction between phytoconstituents and the target protein (NanA) of F. nucleatum.

Statistical analysis: Statistical analysis was done by IBM SPSS version 30.0. One-way ANOVA test was used for intergroup comparison.

Results: The minimum inhibitory concentration was determined to be 0.9 μg/mL for ZO and AS extracts. Both Ginger and Garlic extract showed a dose-dependent activity on F. nucleatum growth, with the highest inhibition at 500 μg/mL. Docking showed N-amyl isovalerate in ginger and furaneol in garlic exhibited the strongest binding affinity with the target protein NanA.

Conclusion: Garlic and ginger extracts both showed better antibacterial activity against F. nucleatum than 3% sodium hypochlorite, indicating that they could potentially utilized as a natural alternative irrigant.

Keywords: Fusobacterium nucleatum; NanA; garlic; ginger; molecular docking.

Figure 1

(a) Three-dimensional (3D) structure of target protein N-acetylneuraminate lyase (NanA), (b) 3D structure of Phytocompound named N-Amyl Isovalerate, (c) Topmost conformation of Docked complex (NanA + N-Amyl Isovalerate)

Figure 2

(a) Three-dimensional (3D) structure of target protein N-acetylneuraminate lyase (NanA), (b) 3D structure of Phytocompound named Furaneol, (c) Topmost conformation of Docked complex (NanA + Furaneol)