The Possible Role of Starch in Oral Calcification: The In Vitro Formation of Hydroxyapatite is Regulated by a Combination of Protein and Mineral Content in Dietary Starch Flour

摘要

The effects of twelve kinds of dietary starch flour, i.e. rice (non-glutinous and glutinous), wheat (soft, medium,and hard), barley (roasted), buckwheat (inner layer and straight), corn, sweet potato, kudzu, and tapioca on in vitro calciumphosphate precipitation were investigated using the pH drop method. The induction time was elongated by the additionof all of the kinds of flour. Although the rate of amorphous calcium phosphate (ACP) formation was not affected, therate of transformation of ACP to hydroxyapatite (HAP) was either stimulated or inhibited by the different types of flour.The following observations were made: (1) When the lipid content below 0.2% (w/w), any of the types of starch had astimulatory effect on the transformation of ACP to HAP. (2) When the lipid content around or above 1.0% (w/w), thevalue of the product of (protein content) ≥ (mineral content) seems to determine the effect of starch.