The surface of the oral cavity is naturally colonised by various microbial species including the probiotic lactic acid bacteria, the presence of which can vary between individuals depending on diet and other lifestyle factors.
However, this natural balance of microorganisms in the mouth can be upset by the presence of pathogens for example Streptococcus mutans, which is thought to be particularly cariogenic, according to Dr Farage Al-Ghazzewi.
Dr Al-Ghazzewi is a researcher with the Glasgow-based company Glycologic, which is currently investigating the use of prebiotics in oral care.
According to Glycologic, the prebiotic glucomannan hydrolysate (GMH) can stimulate the growth of probiotic organisms such as the lactic acid bacteria, while inhibiting the growth of undesirable bacteria such as the S. mutans.
Lactic acid bacteria are those which ferment carbohydrates to produce lactic acid and antibacterial agents, Al-Ghazzewi explained.
Using the GMH as the carbohydrate food for the lactic acid bacteria stimulates their growth, which, due to the production of lactic acid lowers the pH thereby helping to inhibit the growth of microorganisms such as S. mutans.
Lowering the pH of the system is just one way that lactic acid bacteria can inhibit the growth of other, unwanted species, Al-Ghazzewi said.
“Lactic acid bacteria use different mechanisms to inhibit the growth of pathogens such as by lowering pH, producing acids, excreting natural antibiotics, blocking pathogen adhesion or competition for nutrients,” he told CosmeticsDesign-Europe.com.
“The GMH stimulates the growth of lactic acid bacteria at the expense of pathogens,” he added.
The team at Glycologic have performed a number of in vitro tests which illustrate the potential of GMH to stimulate lactic acid bacteria so they outgrow the pathogenic strains.
In vivo trials are now under way, according to the researchers.
The spin off company has been investigating the properties of the prebiotic GMH for some time and earlier this year published research regarding the compound's potential as an anti-acne ingredient.
According to Glycologic, the prebiotic can help the skin bacteria return to their natural equilibrium and lessen the hold that the acne bacteriumhas on the skin of acne sufferers.