Comparative Studies On The Chemical Constituents Of Radix Polygala

Radix polygala, the dried root of Polygala tenuifolia Willd. or P. sibirica L., is a well known traditional Chinese medicine. Early research indicated that the toxicity of the crude could be decreased while keeping the efficiency after the crude was stir-baked with honey. Our studies aimed to compare the similarities and differences of the chemical constituents of Radix polygala before and after stir-baking with honey in order to reveal the mechanism of the processing.The comparative studies were carried out systematically: The contents of 70% Ethanol extract were determined and compared. The contents of the total onjisaponins were determined by means of vanillin-perchloric acid colormetry method and compared. The chemical constituents of the crude and the prepared were studied and compared by TLC method. The method of HPLC fingerprints of Radix polygala and the mutual mode of the prepared had been established. The similarities and differences of the chemical constituents of HPLC fingerprints of the crude and the prepared had been studied comparatively.The average content of the extract of the crude was 36.53% while the prepared was 50.64%, The average content of the total onjisaponins of the crude was 2.090% while the prepared was 2.208%. These results proved that the contents of the extract and the total onjisaponins both increased.The TLC identification results indicated that there were no differences on the chemical constituents of the Petroteum Ether part, the total saponins, the hydrolysis liquid, and water decoction between the crude and the prepared. While the ethyl ether part showed a little difference: the crude had one more composition with no UV absorption but the prepared had no.The degree of similarity between the crude and the prepared was more than 0.9 and this proved that there was no significant change on the kinds of the chemical constituents between the crude and the prepared. The comparison result among the 24 main peaks, which peak area ratio was more than 1%, showed that the content of some peaks increased while other's decreased. The results proved that there was no significant change on the kinds of the chemical constituents between the crude and the prepared, but only some changes on the proportion of the chemical constituents.The constituents of the water decoction, total saponins and n-butyl alcohol part had been comparatively studied with the methods of the HPLC fingerprints, similarity evaluation and the histogram comparison. These results proved that stir-baking with honey had no effect on the kinds of the constituents but on the proportion of the onjisaponins.The active and toxic constituents both were the onjisaponins. The mechanics of the fact that stir-baking with honey could decrease the toxicity but keep the efficacy may because stir-baking with honey could increase the content of the total onjisaponins and at the same time change the proportion of all kinds of the onjisaponins and at last balance at the best proportion with least toxicity and efficient effects.