ABSTRACT
In traditional Chinese medicine, crude drugs are sometime processed and prepared for specific purposes. Rhubarb (Da-huang in Chinese; Daio in Japanese) has been processed by dipping or soaking it in huangjiu (Chinese fermented wine). However, the pharmacologic significance of this liquor processing has not been elucidated thoroughly. In this report, we describe how processing with ethanol altered the levels of the principal compounds in rhubarb: sennoside A, sennoside B, aloe-emodin, rhein, emodin, chrysophanol, physcion, lindleyin, isolindleyin, and total tannins. Liquor-dipping, dipping rhubarb in 16% ethanol for 30 seconds, did not affect the content of sennosides. Thus, the purgative effect of rhubarb is likely to be preserved. Liquor-soaking, soaking rhubarb in ethanol for 12 to 24 hours, the content of sennosides and tannins decreased and the content of anthraquinones increased. Liquor-soaking of rhubarb may increase its anti-bacterial and anti-inflammatory effects, thereby improving blood stasis. These results are in agreement with the descriptions in medicinal literatures published since the Jin and Yuan Dynasties.