著者

土屋 博紀 加藤 博詞 林 英明

出版者

JAPANESE SOCIETY OF ORAL THERAPEUTICS AND PHARMACOLOGY

雑誌

歯科薬物療法 (ISSN:02881012)

巻号頁・発行日

vol.17, no.3, pp.138-146, 1998-12-01 (Released:2010-06-08)

参考文献数

26

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Green tea catechins have been widely used as an anticariogenic or antiplaque additive to mouthrinses, toothpastes, etc. Since their retention in the oral cavity is the determinant for thecaries preventive effects, the oral pharmacokinetic study was performed by assessing salivary concentrations of catechins with time after oral application using high-performance liquid chromatography with diode array detection. The optimized method enabled to simultaneously quantify eight catechins in the concentration range of 0.05-25.0μg/ml in saliva and mouthrinses with high resolution, recovery, and precision. Mouthrinsing experiments with the aqueous solutions of green tea extract (5.0mg/ml) revealed that each catechin maintained the salivary concentration at μg/ml levels for 1-60 min after mouthrinsing, especially (-) -epigal-locatechin gallate and (-) -gallocatechin gallate showed concentrations over 10μg/ml even after 60 min. When using the commercially available mouthrinses containing green tea extract, catechins were found in saliva up to 60 min after mouthrinsing, although their salivary concentrations were much lower. The retentive degree of catechins depended on their concentrations in mouthrinses and the number of times of mouthrinsing. Mouthrinsing with the green tea extract solution under optimal conditions would retain catechins in the oral cavity at least for 60 min after oral application, maintaining their salivary concentrations to show the potential caries preventive effects.

著者

土屋 博紀 加藤 博詞

出版者

JAPANESE SOCIETY OF ORAL THERAPEUTICS AND PHARMACOLOGY

雑誌

歯科薬物療法 (ISSN:02881012)

巻号頁・発行日

vol.17, no.3, pp.147-154, 1998-12-01 (Released:2010-06-08)

参考文献数

30

被引用文献数

1

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Green tea catechins with the anticariogenic activity have been recently revealed to maintain their salivary concentrations after mouthrinsing. The mechanism underlying such retention in the oral cavity was studied by quantitatively evaluating the adsorption of catechins after vortex-mixing with hydroxyapatite, buccal mucosal cells, and proteins in artificial saliva. Treatment with hydroxyapatite decreased catechins in supernatants and such a decrease was more significant by coating hydroxyapatite with saliva as an experimental pellicle. When treating with mucosal cells, unwashed cells decreased catechins in ultrafiltrates more significantly than washed cells. Catechins in ultrafiltrates were decreased by treating with albumin and mucin depending on protein concentrations. These reduced concentrations in supernatants and ultrafiltrates meant the adsorption of catechins to hydroxyapatite, mucosal cells, and proteins. In structural comparison, four gallate esters were superior in the adsorptive activity to the corresponding non-esters. Concentration changes of salivary ctechins after mouthrinsing with green tea extracts showed that the retention of catechins in the oral cavity was associated with their adsorption. The present results suggested that green tea catechins are adsorbed by the teeth, pellicles and oral mucosa, and that salivary proteins such as albumin and mucin are responsible for the adsorption. The adsorbed catechins are considered to gradually be released to maintain the salivary concentrations after oral application.