Brush Away Bacteria!​ (Testing Miswak Toothpaste as a Natural Germ Fighter) ​

Grade:

5

Teacher:

Karen Maninang

This project investigates the antibacterial effectiveness of miswak (Salvadora persica), a natural plant material traditionally used for oral hygiene, when incorporated into toothpaste. Many commercial toothpastes contain synthetic antibacterial agents and chemical additives. This study explores whether miswak, a plant-based alternative, can reduce bacterial growth and potentially serve as a more environmentally sustainable ingredient. To test this, toothpaste samples were prepared with increasing concentrations of miswak (0%, 2%, 5%, and 10%). A control group with no toothpaste was also included. Each sample was tested against Micrococcus luteus, a safe classroom bacterium commonly used in microbiology experiments. Agar plates were inoculated and exposed to the different toothpaste treatments. After incubation under teacher supervision, bacterial growth was observed and measured using a standardized 0–4 growth scoring system. The results demonstrated a clear dose-dependent relationship between miswak concentration and bacterial inhibition. The control and 0% miswak plates showed heavy bacterial growth, confirming normal bacterial proliferation and validating the experimental setup. As the concentration of miswak increased, bacterial growth decreased. The 10% miswak toothpaste showed the strongest antibacterial effect, with very little to no visible bacterial growth. These findings suggest that miswak contains effective natural antibacterial compounds capable of inhibiting bacterial growth. Because miswak is plant-based and biodegradable, it may offer a more environmentally friendly alternative to synthetic antibacterial ingredients in oral care products. This study connects microbiology, environmental science, and traditional plant-based practices to evaluate sustainable health solutions.

Project presentation

Research paper