College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
J Agric Food Chem. 2009 Nov 11;57(21):10252-60. doi: 10.1021/jf902153a.
Even though the degradation of ginsenosides has been thoroughly studied in animals and in vitro using acids, enzymes, and intestinal bacteria, a new degradation method is established for obtaining the ginsenosides Rg(3), Rh(2) and their aglycon 20(S)-protopanaxadiol. This method is based on the microwave irradiation degradation of the major ginsenosides from the Panax quinquefolium L. coupled with foam floatation. The results indicated that ginsenosides Rg(3), Rh(2) and aglycon are not naturally present in Panax quinquefolium L., but are the products obtained simultaneously in the microwave irradiation degradation process. The yield of Rg(3) is 7.69 mg/g and 250 times as high as that obtained from red ginseng, and the transformation rate of total ginsenosides to aglycon is 78.11%. It is important to stress that a new degradation medium, N,N-dimethylformamide, was discovered and, when the medium was used, the transformation rate of total ginsenosides to aglycon was 20.20%. The proposed method is simple, efficient, time saving and a noteworthy improvement on the traditional degradation methods such as acidic hydrolysis, alkaline degradation, enzymatic conversion or microbial degradation.
虽然已经在动物和体外使用酸、酶和肠道细菌对人参皂苷的降解进行了深入研究，但仍建立了一种新的降解方法来获得人参皂苷 Rg(3)、Rh(2)及其苷元 20(S)-原人参二醇。该方法基于微波辐射降解与泡沫浮选相结合从西洋参中提取主要人参皂苷。结果表明，人参皂苷 Rg(3)、Rh(2)和苷元并非天然存在于西洋参中，而是在微波辐射降解过程中同时获得的产物。Rg(3)的收率为 7.69mg/g，是红参的 250 倍，总人参皂苷转化为苷元的转化率为 78.11%。需要强调的是，发现了一种新的降解介质 N,N-二甲基甲酰胺，当使用该介质时，总人参皂苷转化为苷元的转化率为 20.20%。与传统的降解方法如酸水解、碱降解、酶转化或微生物降解相比，该方法简单、高效、省时，是一种显著的改进。
