ABSTRACT
<p><b>OBJECTIVE</b>The purples of this study was to investigate the role of different components of Galla Chinensis extract on the growth of 6 kinds of cariogenic bacteria, and to find out the most effective components of Galla Chinensis extract.</p><p><b>METHODS</b>Four different components (GCE1, GCE2, GCE3 and GCE4) were separated from Galla Chinensis and there antibacterial activities to Streptococcus mutans ATCC 25175, Streptococcus sanguis ATCC 10556, Streptococcus salivarius SS 196, Actinomyces naeslundii WVU 627, Actinomyces viscosus ATCC 19246 and Lactobacillus rhamnosus AC 413 were checked. There effects on the growth curve of Streptococcus mutans ATCC 25175 were also investigated.</p><p><b>RESULTS</b>The most effective part of Galla Chinensis was found to be GCE2 and GCE4, which were found to be a mixture of polyphenol-rich fractions. All of the different components had an inhibitory effect to the growth of Streptococcus mutans ATCC 25175.</p><p><b>CONCLUSION</b>All of the 4 different components of Galla Chinensis extract could inhibit the growth of the tested bacteria. These results suggest that the antibacterial activity of Galla Chinensis extract is caused by a synergistic effect of monomeric polyphenols, which can easily bind to proteins.</p>