<b>Development of a Quick High-Yield Method for the Preparation of Decoctions, Inspired by the “Zhu san Fa” of the Song Period (Part 2)</b> / 日本東洋医学雑誌

ABSTRACT

The IPCD (Immersing Powdered Crude Drugs) method, inspired by the “zhu san fa” which was widely used in the Song period of China, has been developed to prepare Kampo decoctions quickly and easily, with highyield extract from crude drugs. One trouble with the IPCD method occurs when separating the decoction from the muddy residue of the crude drug powder. When powdered ephedra herb is packed in a nonwoven fabric bag and immersed in hot water, yield of the marker compounds is much lower than that obtained when ephedra herb powder is dispersed freely in hot water without a nonwoven fabric bag. Thus the use of a nonwoven fabric bag was shown to be unsuitable with the IPCD method. In investigating an easy and more efficient separation method, we tried decanting with a commercially available wine carafe to separate the decoction and residue. With IPCD followed by decantation using the wine carafe, yields of about 80% decoction volume were obtained as compared with those when cut crude drugs are decocted and filtered using a tea strainer, in 6 of the 7 formulas tried. We find that decantation using a wine carafe is a more practical way of separation in the IPCD method.