Date of Award


Document Type


Degree Name

Master of Science (MS)


College of Education and Human Services


Nutrition and Food Studies

Thesis Sponsor/Dissertation Chair/Project Chair

Charles Feldman

Committee Member

Shahla Wunderlich

Committee Member

Lee Lee


Dental caries is one of the most concerning chronic diseases, Streptococcus mutans is one the most prominent contributing bacterium. S. mutans metabolizes sugar in processed foods to demineralize the tooth’s surface leading to tooth caries. This study focuses on whether green tea polyphenols epigallocatechin gallate (EGCG), and/or its modifications, palmitoyl-epigallocatechin gallate (P-EGCG) and epigallocatechin-3-gallate-stearate (EGCG-S), can reduce the number of S. mutans in different concentrations of sucrose. A colony forming unit assay was utilized to test viability. Results suggested that the tea polyphenols were efficient in inhibiting S. mutans up to 5 grams of sucrose per 100ml of artificial saliva (P<0.05). Then the polyphenols were assessed as a potential additive for cavity-causing foods inhibiting the growth of bacteria on the tooth’s surface. Using 60% and 70% dark chocolate as a marker, the results indicated three polyphenols are effective in reducing S. mutans. EGCG-S and P-EGCG inhibited S. mutans significantly in the 60% dark chocolate with an inhibition rate of 70.0% ± 1.90% and 81.7% ± 2.69%, respectively (P<0.05). This study suggests that EGCG, EGCG-S, and P-EGCG have the potential to be used as food additives for dark chocolate.