Research Paper|Volume 14, Issue 5|pp 2221—2238

Impact of the food grade heat-killed probiotic and postbiotic oral lozenges in oral hygiene

Chiao-Wen Lin^1,², Yi-Tzu Chen^1,^2,³, Hsieh-Hsun Ho⁴, Yi-Wei Kuo⁴, Wen-Yang Lin⁴, Jui-Fen Chen⁴, Jia-Hung Lin⁴, Cheng-Ruei Liu⁴, Chi-Huei Lin⁴, Yao-Tsung Yeh⁵, Ching-Wei Chen⁴, Yu-Fen Huang⁴, Chen-Hung Hsu⁴, Pei-Shan Hsieh⁴, Shun-Fa Yang^6,⁷

¹Institute of Oral Sciences, Chung Shan Medical University, Taichung, Taiwan
²Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan
³School of Dentistry, Chung Shan Medical University, Taichung, Taiwan
⁴Research and Development Department, Bioflag Biotech Co., Ltd., Tainan, Taiwan
⁵Aging and Disease Prevention Research Center, Fooyin University, Kaohsiung, Taiwan
⁶Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan
⁷Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan

Received: November 10, 2021Accepted: February 22, 2022Published: March 2, 2022

https://doi.org/10.18632/aging.203923

Copyright: © 2022 Lin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

The oral cavity plays a crucial role in food digestion and immune protection. Thus, maintaining oral health is necessary. Postbiotic and heat-killed probiotic cells have shown increased antibacterial potential with stable viability compared with live strains. However, clinical evidence regarding their effect on oral health is insufficient. Therefore, in this study, we tested postbiotic lozenges of Lactobacillus salivarius subsp. salicinius AP-32, L. paracasei ET-66, and L. plantarum LPL28 and heat-killed probiotic lozenges of L. salivarius subsp. salicinius AP-32 and L. paracasei ET-66 for their effect on oral health. In total, 75 healthy individuals were blindly and randomly divided into placebo, postbiotic lozenge, and heat-killed probiotic lozenge groups and were administered the respective lozenge type for 4 weeks. Postbiotic and heat-killed probiotic lozenge groups demonstrated antibacterial activities with a considerable increase in L. salivarius in their oral cavity. Furthermore, their salivary immunoglobulin A, Lactobacillus, and Bifidobacterium increased. Subjective questionnaires completed by the participants indicated that participants in both the experimental groups developed better oral health and intestinal conditions than those in the placebo group. Overall, our study revealed that a food additive in the form of an oral postbiotic or heat-killed probiotic lozenge may effectively enhance oral immunity, inhibit the growth of oral pathogens, and increase the numbers of beneficial oral microbiota.