大黃、首烏及決明子E類配醣體之定量   全文下載

Determination of Anthraquinone Glycosides in Rhei Rhizome, Polygoni Multiflori Radix, and Cassia Torae Semen

中藥所含之多酚類成分主要以配醣體之形式存在，而許多配醣體需經過腸道內之酵素或菌叢水解成極性較低之?元，方可被人體吸收，因此在品管上若儘量能掌握各具活性?元之總配醣體含量，則更貼近實際可為人體吸收之量，以再提升中藥之品質管制。但目前各國藥典對於中藥之品質管制只限於單一配醣體或?元之定量，然而，這些尚不足以反應出中藥之實際效價，因此本研究以酸水解方式，定量大黃、生首烏、製首烏及決明子四種中藥酸水解前後之?元總量，以進一步了解中藥可為人體吸收成分之含量。將四種藥材水煎劑，加酸置加熱水浴中處理後，以高效液相層析儀定量大黃之aloe-emodin、rhein、emodin、chrysophanol 及physcion，生首烏、製首烏之emodin 及physcion，以及決明子之chrysophanol 及physcion 之酸水解前後含量變化，並藉此回推其總配醣體含量。結果顯示，大黃水煎劑之aloe-emodin、emodin、chrysophanol 及physcion 之含量在水解後分別增加154%、145%、127% 及95%，生首烏水煎劑之emodin 及physcion 分別增加1174 % 及800%，主要以配醣體形式存在水煎劑中；而決明子水煎劑之chrysophanol 及physcion 則幾乎以配醣體存在；至於製首烏之emodin 及physcion 含量在水解前後無明顯差異。本研究此建立之方法，可應用於大黃、生首烏及決明子之總配醣體含量測定，而製首烏建議直接測定其?元含量。

Polyphenols are predominantly present as glycosides in Chinese herbs, and many of them are hydrolyzed to less polar aglycones by enzymes or bacteria in the intestines and then became absorbable. Therefore, it is more appropriate to use the amount of total glycosides as the standard for the quality control of Chinese herbs since most glycosides are assimilated with the aglycone form after oral administration. Currently there are limited requirements for the quality control of crude drugs in pharmacopoeias in many countries, and assays for only one glycoside or aglycone are required. However, these requirements cannot ensure the efficacy of Chinese herbs. This study attempted to determine aglycones in Rhei rhizome (RR), crude Polygoni multiflori radix (cPM), processed Polygoni multiflori radix (pPM), and Cassiae torae semen (CS) after acid hydrolysis in order to investigate the total amount of absorbable components. The decoctions of these four Chinese herbs were hydrolyzed by hydrochloric acid in water bath. Before and after hydrolysis, the contents of aloe-emodin, rhein, emodin, chrysophanol and physcion from RR, emodin and physcion from cPM and pPM, and chrysophanol and physcion from CS were determined by HPLC. The total glycoside contents were calculated by subtracting the amounts of aglycones in decoction from those in hydrolysate. The results showed that the contents of aloe-emodin, emodin, chrysophanol and physcion in RR after acid hydrolysis increased by 154%, 145%, 127% and 95%, respectively. Emodin and physcion in cPM increased by 1174% and 800%, respectively. Chrysophanol and physcion in CS existed solely as glycoside forms. However, emodin and physcion in pPM displayed no significant difference between decoction and hydrolysate. The methods developed in this study are suitable for the determination of total glycosides in RR, cPM, and CS, whereas pPM was suggested to determine the contents of aglycones directly.