In vitro inhibition of Streptococcus mutans by probiotic yogurt fortified with Lactobacillus paracasei and Sargassum angustifolium protein hydrolysate: a functional yogurt for teeth decay prevention

  • Sara Jafarirad Department of Food Science and Technology, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran
  • Leila Nateghi Department of Food Science and Technology, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran
  • Masoumeh Moslemi Halal Research Center of IRI, Iran Food and Drug Administration, Ministry of Health and Medical Education, Tehran, Iran
  • Kian Pahlevan Afshari Department of Animal Science, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran
  • Ali Ahmadi Hassan Abad Department of Food Science and Technology, Faculty of Agriculture, Shiraz University, Shiraz, Iran
  • Kianoush Khosravi-Darani Department of Food Technology Research, National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Keywords: Dental caries; Sargassum; Calcium alginate; Encapsulation; Lactobacillus paracasei; Streptococcus mutans

Abstract

Background and Objectives: Probiotic yogurts enriched with Lactobacillus paracasei (L. paracasei), protein hydrolysates derived from Sargassum angustifolium macroalgae (SAPH), and encapsulated SAPH were formulated to inhibit Streptococ- cus mutans (S. mutans), the primary bacterium responsible for dental caries.

Materials and Methods: The yogurt samples were evaluated for physicochemical, microbiological, and sensory character-

istics.

Results: On day 21, the yogurt supplemented with L. paracasei demonstrated the greatest titratable acidity (97.35°D), the lowest pH value (4.24), reduced syneresis, and enhanced antioxidant, antihypertensive, and rheological properties. In terms of antibacterial activity, the lowest S. mutans count was detected in formulations containing free SAPH, either alone or in combination with L. paracasei. Conversely, yogurts formulated with encapsulated SAPH exhibited higher survival rates of both L. paracasei and S. mutans compared to those containing the free form of SAPH.        

Conclusion: The findings indicated that although the probiotic yogurt containing free SAPH was more effective in reducing S. mutans levels within the yogurt matrix, the encapsulated form achieved an acceptable level of antibacterial activity while contributing to improved sensory acceptance.

Published
2025-06-01
Section
Articles