| Abstract
| - The inhibitory effects of apple polyphenols (APP) on the synthesis of water-insoluble glucans byglucosyltransferases (GTF) of streptococci of the mutans group and on the sucrose-dependentadherence of the bacterial cells were examined in vitro. APP markedly inhibited the activity ofGTF purified from the cariogenic bacterial cells. However, APP showed no significant effect on thegrowth of the cariogenic bacteria. The strongest GTF inhibitors in APP were apple condensed tannins(ACT), a mixture of procyanidins. The 50% inhibitory doses of ACT against the GTF of S. sobrinusand that of S. mutans were 1.5 μg/mL and 5 μg/mL, respectively. The ACT efficacy largely dependedupon the degree of polymerization. Interestingly, while the other polyphenols known to inhibit GTFsuch as tannic acid markedly inhibited salivary α-amylase activity, APP and ACT only scarcelyinhibited that enzyme activity. This means that APP and ACT might selectively inhibit the bacterialGTF activity under oral conditions. Keywords: Polyphenol; procyanidin; apple; mutans streptococci; glucosyltransferase
|
