Beijing Key Laboratory for Analytical Methods and Instrumentation, Department of Chemistry, Tsinghua University, Beijing 100084, People's Republic of China.
J Agric Food Chem. 2012 Aug 22;60(33):8213-24. doi: 10.1021/jf301116x. Epub 2012 Aug 9.
The purpose of this study is to evaluate the steaming-induced chemical transformation of red ginseng manufactured from fresh ginseng by means of simultaneous quantitative and qualitative analyses with a combinative high-performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-ESI-MS/MS(n)) technique. Thirty-six ginsenosides were identified in red ginseng and white ginseng by comparing the mass spectrum and/or matching the empirical molecular formula with that of known published compounds, and 11 of them were determined to be newly generated during the red ginseng preparatory process. The mechanisms involved were further deduced to be hydrolysis, dehydration, isomerization, and decarboxylation at C-20, and hydrolysis also occurs at C-3 or C-6 of the original ginsenosides through the mimic process of steaming and heating in laboratory. The multicomponent quantification fingerprint of ginseng was also established by HPLC-UV method, and the contents of 12 ginsenosides in red and white ginsengs from different sources were determined simultaneously. The ratio of the total content of determined malonyl ginsenosides to the corresponding neutral ginsenosides (T(m-PPD)/T(PPD)) in white ginseng ranged from 0.46 to 0.62 and from 0 to 0.19 in red ginseng. The validated method is expected to provide an effective approach to standardize the processing procedures of ginseng products and regulate the usage of ginseng in Traditional Chinese Medical prescription.
本研究旨在通过联用高效液相色谱-电喷雾串联质谱(HPLC-ESI-MS/MS(n))技术对新鲜人参制成的红参进行蒸制诱导的化学转化进行同时定量和定性分析。通过比较质谱和/或与已知发表化合物的经验式分子匹配,在红参和白参中鉴定出 36 种人参皂苷,其中 11 种被确定为在红参制备过程中生成的新化合物。通过模拟蒸制和实验室加热过程中的水解、脱水、异构化和脱羧反应,推断出涉及的机制发生在 C-20 上,原始人参皂苷的 C-3 或 C-6 也发生水解反应。还通过 HPLC-UV 方法建立了人参的多组分定量指纹图谱,并同时测定了不同来源的红参和白参中 12 种人参皂苷的含量。白参中丙二酰基人参皂苷与相应的中性人参皂苷(T(m-PPD)/T(PPD))总含量的比值范围为 0.46-0.62,而红参中的比值范围为 0-0.19。该验证方法有望为规范人参产品的加工工艺和规范人参在中药方剂中的使用提供有效的方法。