Effect of mirabilitum in formularization: Change of prolyl endopeptidase inhibitory activity and of constituents using the preparation method of Tokaku-joki-to (Persia and Rhubarb combination)

Abstract

To clarify the effect of Mirabilitum in formularization, change of prolyl endopeptidase inhibitory activity and of constituents using the preparation method of a Kampo formula Tokaku-joki-to (Persia and Rhubarb combination) was examined by the liquid chromatography - mass spectroscopy (LC-MS) method. Mirabilitum under boiling condition caused qualitative and quantitative change of the constituents through hydrolysis which caused a change of its activity. This was considered to be the main reason the classical Chinese medical book "Shang hah lun" specified that Mirabilitum should be added at a later stage of decoction.