title: Effect of propylgallate on a dipalmitoylphosphatidylglycerol and calcium mixture.
abstract: Effect of propylgallate (PrG) on the thermotropic behavior of mixtures of dipalmitoylphosphatidylglycerol (DPPG) and Ca2+ was studied by means of differential scanning calorimetry (DSC). In the case of DPPG or DPPG/Ca (molar ratio, 15 : 1), the transition temperature (Tm) of the main transition and the subtransition decreased from 40 degrees C to 29 degrees C and from 29 degrees C to 20 degrees C, respectively, with an increase in the concentration of PrG. The addition of PrG to the DPPG/Ca mixture induced a shoulder on the high temperature side in the reheating scan. Neither PrG nor low concentrations of Ca2+ bind to the Lc phase of DPPG. When the molar ratio of DPPG to Ca was 1 : 1, the subtransition did not occur, that is, only the main transition (Tm = 90 degrees C) appeared. The Tm of the main transition was slightly affected by PrG. On the addition of PrG, another metastable endothermic transition peak (Tm = 78 degrees C) appeared. It is concluded that Ca2+ and PrG inhibit each other's binding.
authors.affiliation: Department of Food and Nutrition, Hiroshima Women's University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Mukai
authors.forename: M
authors.initials: M
authors.lastname: Ishinaga
mesh_terms: D002118:Calcium; D002152:Calorimetry, Differential Scanning; D005707:Gallic Acid / Q000031:analogs & derivatives*; D010715:Phosphatidylglycerols; D011435:Propyl Gallate / Q000494:pharmacology*; D013696:Temperature
chemical_list: D010715:Phosphatidylglycerols; D005707:Gallic Acid; D011435:Propyl Gallate; D002118:Calcium; C030345:1,2-dipalmitoylphosphatidylglycerol