Abstract
INTRODUCTION: Molecular docking is a key computational method to predict interactions between small molecules and proteins. This study evaluated the antibacterial potential of Cissus quadrangularis and Allium sativum against Streptococcus oralis using both in silico and in vitro approaches. METHODS: Plant extracts were prepared via Soxhlet extraction using petroleum ether and analysed through gas chromatography-mass spectrometry. Molecular docking studies revealed that 3-deoxy-D-mannoic lactone from Allium sativum (binding affinity: -4.9 kcal/mol) and 1,4,7,10,13,16-hexaoxacyclononadecane from Cissus quadrangularis (binding affinity: -5.0 kcal/mol) exhibited strong binding affinities with the Pilus islet-2 protein of Streptococcus oralis, indicating potential interference with bacterial adhesion and virulence. The active compounds were isolated using thin-layer chromatography and high-performance liquid chromatography. RESULTS: In vitro antibacterial assays demonstrated inhibition zones of 12.85 ± 0.21 mm for Allium sativum and 12.6 ± 0.14 mm for Cissus quadrangularis. Antioxidant activity, assessed by DPPH assay, showed lower IC₅₀ values for Allium sativum (77.21 µg/ml) compared to Cissus quadrangularis (84.41 µg/ml). CONCLUSION: These findings underscore the potential of 3-deoxy-D-mannoic lactone as a potential antimicrobial candidate against Streptococcus oralis, contributing to novel therapeutic strategies for periodontitis.