Influence of Water Properties on the Contents of Aconitine-Type Diester Alkaloids in the Decoctions of Unprocessed Aconite Root / 日本東洋医学雑誌

ABSTRACT

The decoctions of unprocessed aconite root (uzu) were prepared with the tap water samples collected in Tianjin and Shanghai in China, and the contents of alkaloids in the decoctions were compared to those prepared with purified water or with tap water collected in Niigata, Japan. The contents of aconitine-type diester alkaloids (ADA) in the decoctions prepared with tap water collected in China were significantly lower than those with purified water or tap water in Niigata. It was speculated that this difference appeared by buffering effect of bicarbonic anion in tap water in China to decline pH of the decoction. When uzu was decocted with glycyrrhiza, ginger, or jujube, the contents of ADA in the decoctions exhibited the tendency to have higher levels than those prepared using unprocessed aconite root singly, and also this tendency was observed more remarkably when the decoctions were prepared with tap water collected in China. It was suggested that even the decocting period was fixed, unexpected change of the contents of ADAs might be induced by the differences in the properties of water used for decoction or the crude drugs decocted with aconite root. The physicians in the era when “Songban Shanghanlun” had established may have adjusted the contents of ADA in the decoction by carefully choosing the crude drugs combined to aconite root.