Potential of Basil Leaves (Ocimum x africanum Lour) as a Herbal Mouthwash: Phytochemical Screening, Formulation, Physical Evaluation and Antibacterial Activity Againts Streptococcus mutans

Abstract

Oral diseases remain a major global public health problem, with dental caries being one of the most prevalent conditions primarily caused by Streptococcus mutans. Although commercial mouthwashes are effective in controlling oral microorganisms, their prolonged use may cause undesirable side effects, prompting the development of herbal alternatives. This study aimed to evaluate the potential of Ocimum × africanum Lour. leaves as an herbal mouthwash through phytochemical screening, formulation, physical quality evaluation, and antibacterial activity against Streptococcus mutans. Basil leaves were extracted by maceration using 96% ethanol and formulated into mouthwash preparations containing extract concentrations of 2.5% (F1), 5% (F2), and 10% (F3). Phytochemical screening was performed to identify the major secondary metabolites. The formulations were evaluated for organoleptic properties, pH, viscosity, specific gravity, and freeze–thaw stability. Antibacterial activity was determined using the paper disk diffusion method. The extract contained flavonoids, alkaloids, tannins, saponins, and steroids. All formulations exhibited acceptable physical characteristics and remained stable throughout the stability test. The antibacterial assay demonstrated inhibition zones of 7.15 mm, 7.06 mm, and 7.41 mm for F1, F2, and F3, respectively, indicating moderate antibacterial activity, with the 10% extract formulation showing the highest inhibitory effect. Statistical analysis demonstrated significant differences among treatment groups (p < 0.05), although post-hoc analysis indicated no significant difference among extract concentrations. These findings suggest that Ocimum × africanum leaf extract has promising potential as a natural antibacterial ingredient for herbal mouthwash formulations. Further studies involving minimum inhibitory concentration, long-term stability, and clinical evaluation are recommended.