Characteristics of antimicrobial activity of Streptococcus salivarius K12 by culture condition

Abstract

Purpose: The purpose of this study was to examine effects of culture conditions on the growth and antibacterial activity of Streptococcus salivarius K12. Materials and Methods: S. salivarius K12 was cultivated in medium containing animal and plant protein or in medium of neutral and acidic conditions. The growth of S. salivarius K12 was measured every 2 hours by a spectrophotometer. The antimicrobial activity of S. salivarius K12 against Streptococcus mutans and Porphyromonas gingivalis was investigated by the susceptibility assay using the spent culture medium. Results: the growth of S. salivarius K12 showed faster in medium containing plant protein and neutral pH condition. The antimicrobial and antifungal activity of S. salivarius K12 appeared stronger in medium containing plant protein than animal proteins. Conclusion: For application of S. salivarius K12 to bacterial oral disease, co-substances may be needed for S. salivarius K12 to colonize in the oral cavity and enhance the antimicrobial activity. (J Dent Rehabil Appl Sci 2021;37(4):244-50) incubated in the presence or absence of the SCM of S. salivarius K12. Bacterial growth was measured by a spectrophotometer. The experiments were carried out 4 times in duplicate, and data are expressed as mean ± standard deviation. * indicates statistically significant differences compared control group.