Probiotics are not only about gut health. The friendly bugs have also been touted to become the next blockbuster functional ingredients in gum and mints by Euromonitor. But which strains show the most potential, where does the science stand, and how do they work?
There are several different avenues for researchers to explore for probiotics to beneficially impact oral health, ranging from reducing dental plaque-related diseases, such as caries, gingivitis and periodontitis, or even reducing bad breath (halitosis).
One of the best known probiotics for oral health was developed by scientists at the University of Otago in New Zealand: BLIS K12 is a specific strain of Streptococcus salivarius (S. salivarius), which secretes powerful antimicrobial molecules called BLIS: Bacteriocin-Like-Inhibitory Substances.
BLIS K12 is an oral probiotic that is said to support healthy bacteria in the mouth for long-term fresh breath and immune support.
The ingredient was recently added to Stratum Nutrition’s portfolio of specialty bioactive ingredients.
As reported by NutraIngredients, the ingredient’s list of potential benefits may also extend to inhibiting the growth of the yeast responsible for oral thrush, or candidiasis (Applied and Environmental Microbiology , Vol. 78, pp. 2190-2199).
"This research represents further evidence that the BLIS K12 probiotic plays an important role in maintaining good oral health and protecting the mouth and throat from the potential of invading pathogens," said Dr Barry Richardson, CEO of BLIS Technologies.
Binding S. mutans
At the International Probiotics Association’s (IPA) World Congress in Miami in 2010, Dr Christine Lang from Berlin-based Organobalance told attendees that the concept of probiotics for oral health centers on Streptococcus mutans, the main bacteria associated with tooth decay. S. mutans binds to teeth via aggregation, said Lang, forming dental plaque. The bacteria then convert sugar to acid, which attacks the enamel of the teeth.
Dr Lang and her co-workers screened 700 Lactobacillus strains, and found six which could bind to S. mutans. Of these, Lactobacillus paracasei was found to aggregate best with S. mutans.
The bacteria work in the presence of saliva and in the presence of sugars, including xylitol and sorbitol, so it can be formulated into candies and gums, said Dr Lang. She notes that these have been tested, as well as delivery as toothpaste, and they work. The bacteria are also active under the pH range 4 to 8, she added.
The probiotic is included in BASF’s functional ingredient Pro-t-action. The firm claims that it is tasteless, odorless, pH-neutral and works within 10 seconds, and touts application in everything from chewing gum and sugar-free sweets to toothpaste and mouthwash.
While gums and lozenges appear to be the delivery systems of choice, an innovative approach to tackling S. mutans was reported by researchers from the College of Dental Sciences and Research in Mullana, India in 2011. According to findings published in Acta Odontologica Scandinavica (Vol. 69, pp. 389-394), ice cream containing Bifidobacterium lactis Bb-12 ATCC27536 and Lactobacillus acidophilus La-5 was associated with a statistical reduction in levels of S. mutans.
Gingivitis, halitosis, et al.
The scientific literature is also peppered with additional examples of beneficial bacterial strains with potential oral health benefits: A study with 42 subjects with moderate gingivitis published in the journal Acta Odontologica Scandinavica showed benefits of L. reuteri prodentis against gingivitis, otherwise known as bleeding or inflamed gums.
Danish researchers used BioGaia’s proprietary probiotic strain and found its interaction with the immune system could boost oral health.
Earlier this year, scientists from the University of Copenhagen reported that chewing gum formulated with L. reuteri DSM 17938 and L. reuteri ATCC PTA 5289 was capable of significantly reduce halitosis (Acta Odontologica Scandinavica, Vol. 70, pp. 246-250).
A pilot study using Yakult’s probiotic milk drink also suggested oral health benefits for the Lactobacillus casei strain Shirota to reduce inflammation and bleeding in the mouth linked to gingivitis and gum disease (periodontitis) based on its influence of the immune system. (Journal of Clinical Periodontology, 2009, Vol. 36, pp. 850-856).