
Lactobacillus Strains and Sugar Fermentation: All Sugars Are Equal
Lactobacillus Strains and Sugar Fermentation All Sugars Are Equal Lactobacillus Strains and Sugar Fermentation All Sugars Are Equal Are all sugars created equally? In the case of Lactobacillus, and its ability to ferment, the answer is a resounding yes.
Lactobacillus Strains and Sugar Fermentation: All Sugars Are Equal
Are all sugars created equally? In the case of Lactobacillus, and its ability to ferment, the answer is a resounding yes. A new study, carried out by Swedish researchers and published in Clinical Oral Investigations, examined the pH-lowering potential of certain strains of Lactobacillus to ferment sugars and sugar alcohols among subjects with hyposalivation (resulting from radiation or Sjögren’s syndrome) and healthy controls.
Previous studies suggest that patients with hyposalivation harbor high numbers of Lactobacillus in saliva and plaque. This is worrisome, as fermentation of sugar produces acid, which supports the demineralization of enamel. The goal of this study was to analyze these fermentation patterns of sugar and sugar substitutes among participants with normal salivary function compared to those with hyposalivation.
Researchers looked at 50 strains of Lactobacillus isolated from supragingival plaque, fermenting each strain in a vial containing 1% glucose, fructose, sucrose, mannitol, sorbitol, or xylitol. After 24 hours and 48 hours of incubation, each strain was examined twice for growth and pH, and the mean was calculated.
No significant differences were found between species isolated from the two groups. Each strain of Lactobacillus grew better with sugars versus sugar alcohols, and all three sugar substitutes fermented comparatively. Post-incubation examination revealed that with glucose, 74% of lactobacilli strains could lower pH to ?5.5, and with sucrose, 70% of lactobacilli strains produced the same effect on pH. All strains lowered pH to ?5.5 when fructose was used. Among sugar alcohols, mannitol lowered pH in 52% of strains; sorbitol in 49% of strains; and xylitol lowered pH in 37% of strains.
These results demonstrate that no sugar is “safe” when it comes to oral health. As the authors report, many strains of Lactobacillus are able to ferment both sugar and sugar alcohols, producing acids that lower pH levels and increase the potential for enamel demineralization. The use of sugar-free products may protect the oral flora from negative effects of sugar.