Evaluation of the cariogenic potential of a probiotic candidate strain Lactobacillus gasseri YIT 12321

Ayako Okada; Susumu Imai; Tomohiro Kikuchi; Khairul Matin; Ryoko Otsuka; Tomohiko Terai; Takekazu Okumura; Takatsugu Yamamoto; Nobuhiro Hanada

doi:10.1016/j.archoralbio.2022.105364

Evaluation of the cariogenic potential of a probiotic candidate strain Lactobacillus gasseri YIT 12321

Arch Oral Biol. 2022 Apr:136:105364. doi: 10.1016/j.archoralbio.2022.105364. Epub 2022 Feb 2.

Authors

Ayako Okada¹, Susumu Imai², Tomohiro Kikuchi³, Khairul Matin⁴, Ryoko Otsuka⁵, Tomohiko Terai⁶, Takekazu Okumura⁶, Takatsugu Yamamoto⁷, Nobuhiro Hanada⁵

Affiliations

¹ Department of Operative Dentistry, Tsurumi University School of Dental Medicine, 2-1-3, Tsurumi, Yokohama 230-8501, Japan; Department of Translational Research, Tsurumi University School of Dental Medicine, 2-1-3, Tsurumi, Yokohama 230-8501, Japan.
² Department of Translational Research, Tsurumi University School of Dental Medicine, 2-1-3, Tsurumi, Yokohama 230-8501, Japan. Electronic address: imai-s@tsurumi-u.ac.jp.
³ Department of Translational Research, Tsurumi University School of Dental Medicine, 2-1-3, Tsurumi, Yokohama 230-8501, Japan; Kikuchi Dental Clinic, 963-5, Anjojimachi, Matsuyama 791-8006, Japan.
⁴ Department of Translational Research, Tsurumi University School of Dental Medicine, 2-1-3, Tsurumi, Yokohama 230-8501, Japan; Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, National University Corporation Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
⁵ Department of Translational Research, Tsurumi University School of Dental Medicine, 2-1-3, Tsurumi, Yokohama 230-8501, Japan.
⁶ Yakult Central Institute, 1796, Kunitachi, Tokyo 186-8650, Japan.
⁷ Department of Operative Dentistry, Tsurumi University School of Dental Medicine, 2-1-3, Tsurumi, Yokohama 230-8501, Japan.

PMID: 35150950
DOI: 10.1016/j.archoralbio.2022.105364

Abstract

Objective: This study was designed to evaluate the cariogenic potential of Lactobacillus gasseri YIT 12321.

Design: L. gasseri YIT 12321 was isolated from the human oral cavity as a probiotic candidate strain. Three types of experimental biofilm formations on bovine enamel specimens were assessed using Streptococcus sobrinus ATCC 33478, L. gasseri YIT 12321, and a co-culture of S. sobrinus and L. gasseri YIT 12321 in vitro. L. gasseri YIT 12321 was analyzed for its ability to utilize seven carbohydrates. L. gasseri YIT 12321 was cultured in tryptic soy broth without dextrose and containing a test carbohydrate at 37 °C for 16 h.

Results: The decrease in pH in the region under the biofilm produced by L. gasseri YIT 12321 was unusually slow, and the pH was maintained above 5.5 for 16 h. The amount of biofilm and the reduction in enamel hardness were minimal in the L. gasseri YIT 12321 group among the three experimental groups. The amount of co-culture-derived biofilms was less than that of S. sobrinus biofilms. When S. sobrinus was grown using sucrose, the pH decreased to 3.98. In contrast, L. gasseri YIT 12321 cultures maintained the pH above the critical pH for dentin demineralization.

Conclusions: L. gasseri YIT 12321 is suggested to have a low cariogenic potential. The application of this strain as a probiotic may contribute to oral safety.

Keywords: Artificial mouth system; Carbohydrate utilization; Cariogenic biofilm; Lactobacillus gasseri YIT 12321; Probiotic.

MeSH terms

Animals
Biofilms
Cattle
Dental Caries* / prevention & control
Dental Enamel
Humans
Lactobacillus gasseri*
Probiotics* / pharmacology
Streptococcus mutans
Streptococcus sobrinus