Tooth decay (caries) is caused by bacteria breaking down teeth. Here bacteria create acids by utilizing food material, such as sugar, affixed to the surface of enamel. The common bacterium involved in the tooth decay process is Streptococcus mutans. This organism breaks down sugar to form plaque. Caries is one of the most common diseases in the world, and without effective brushing of teeth and the use of mouthwashes, the disease can cause considerable pain.
A new study suggests that natural products, extracted from plants, could help with the fight against the disease. The compound is called trans-chalcone. It is found in liquorice root. The chemical appears to counteract a specific enzyme, termed Sortase A. This enzyme allows bacteria to grow and divide within the mouth.
Liquorice (sometimes spelt licorice) is the root of the herb Glycyrrhiza glabra. It has a sweet flavour. Medically the chemical has anti-viral, anti-microbial, anti-inflammatory properties. It also works, in certain doses, as a laxative.
Studies have shown that preventing the activity of the enzyme prevents the bacteria from forming a biofilm. A biofilm is a protective slime-like layer that protects a microbial community from attack from chemicals (and toothpaste.) According to a research review: “Once a biofilm has formed, it constitutes a micro-niche that provides bacteria with an environment that is highly conducive to their survival while also protecting them from various types of aggression from outside, such as flows of liquids and changes in pH or temperature.”
The chemical in the liquorice achieved this. The activities were confirmed through tests and the use of three-dimensional modelling. This has led the researchers to suggest that oral care products with an addition of this compound could significantly improve dental hygiene.
The research was carried out at the University of Edinburgh. The findings have been reported to the journal Chemical Communications. The paper is called “Molecular Basis of Streptococcus mutans Sortase A Inhibition by the Flavonoid Natural Product trans-Chalcone.”
