| Project/Area Number |
60480452
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
小児・社会系歯学
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| Research Institution | Tokyo Dental College |
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Principal Investigator |
MATSUKUBO Takashi Tokyo Dental Coolege, 歯学部, 助教授 (90112804)
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| Co-Investigator(Kenkyū-buntansha) |
YAMAMOTO Hideki Tokyo Dental College, 口腔衛生学, 助手 (50191432)
MAKI Yoshinobu Tokyo Dental College, 口腔衛生学, 講師 (80125012)
HOJYO Sachiko Tohoku University, School Of Dentistry, 歯学部・口腔生化学, 助手 (90005033)
TAKAESU Yoshinori Tokyo Dental College, 口腔衛生学, 教授 (60048303)
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| Project Period (FY) |
1985 – 1986
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| Project Status |
Completed (Fiscal Year 1986)
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| Budget Amount *help |
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 1986: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1985: ¥2,400,000 (Direct Cost: ¥2,400,000)
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| Keywords | Food stuffs / Buffer capacity / Cariogenicity / Plaque pH response / IS-FET電極 |
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| Research Abstract |
The methods to decrease acidogenicity of food stuffs have been considered to be most effective on decreasing their cariogenicity. The purpose of this study was to evaluate the effort of buffer capacity of the substances, especially low molecular chitosan(LMCS), in addition to a glucose solution upon acid production of S.mutans cell suspensions and human plaque pH responses.
The five kinds of test substances having buffer capacity were used in this study. In addition, seven LMCS with different molecular weight and degree of deacetylation(DAC) were prepared for this study. Acid production in vitro were evaluated by the Automatic Titration Method and pH-fall experiment using S.mutans cell suspensions and also the constant addition method of lactate was used in this study. Acid production in vivo was evaluated by an ion-sensitive transistor electrode. Data from five human volunteers were obtained in this study. Evaluation of the effort of each LMCS was determined by four criteria, 1)area(exp./cont.) ratio below pH 5.5, 2)time(exp./cont.) ratio below pH 5.5, 3)minimal pH, 4) pH.
The most effective effort on pH drop in vitro from pH 7.0 was obtained by the substances, ex. LMCS(pKa:6.4) and malate(pKa:6.2), with pKa:around 6.5. The additions(1%) of five LMCS to a 5% glucose solution decreased plaque pH drop and the pH returned rapidly to resting value. The most effective effort was obtained with the addition of two LMCS with MW:3,000 and 500, DAC:50 and 95%, respectively. The two LMCS resulted in statistically significant differences (p<0.01) in the four criteria.
The findings indicate that low molecular chitosan is useful as a food additive to decrease acidogenicity of foods.
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