Antimicrobial Efficacy of Teucrium polium L. Extracts for Dental Caries: Green Extraction Techniques and Bioactive Compounds

Tooth decay is a global epidemic, but the next weapon against it might come from a humble desert plant—not a lab-grown chemical.

Dental caries is the most common chronic disease worldwide, and bacteria are the culprits behind it. As antibiotic resistance grows, scientists are turning to nature for answers. This study tested three types of extracts from Teucrium polium, a member of the mint family, against seven bacteria that cause tooth decay. The extracts—ethanolic, hydroethanolic, and aqueous—were tested at concentrations from 0.1 to 1000 ppm, revealing that the solvent matters as much as the plant itself. The hydroethanolic extract was the most potent against Streptococcus mutans, the main cavity-causing bacterium, with a minimum inhibitory concentration (MIC) of 1.24 mg/mL. The ethanolic extract excelled against several others, including S. sanguinis, S. sobrinus, and L. fermentum, with MICs as low as 1.36 mg/mL. Aqueous extracts were the weakest overall, though they still worked against S. epidermidis. The study's most striking finding: mouthwashes containing ethanolic or hydroethanolic extracts at just 2.44 mg/L effectively blocked all tested oral bacteria. This suggests that a natural, plant-based rinse could one day rival synthetic mouthwashes. The authors recommend combining the right extract with the right solvent for targeted action. Future research will explore how these compounds work and whether they can outperform conventional treatments, opening the door to innovative dental therapies.

Key Points

• Hydroethanolic extract best against S. mutans, MIC 1.24 mg/mL.
• Ethanolic extract most effective overall for multiple bacteria.
• Mouthwash at 2.44 mg/L inhibited all tested oral bacteria.