Huang Liying, Chen Tianwen, Ye Zhao, Chen Guonan
Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety (Fuzhou University), and Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002, China.
J Mass Spectrom. 2007 Jul;42(7):910-7. doi: 10.1002/jms.1228.
Oleanolic acid (OA) and ursolic acid (UA) are the two important bioactive compounds in Anoectochilus roxburghii (wall) Lindl (A. roxburghii), which has been used as a traditional Chinese medicine. So far, there has been no report to indicate that A. roxburghii contains these two bioactive compounds. It is necessary to develop an effective method to extract and analyze OA and UA in A. roxburghii. In this paper, a quantitative method, consisting of supercritical fluid extraction (SFE) followed by liquid chromatography-atmospheric pressure chemical ionization-ion trap mass spectrometry (LC-APCI-IT-MS) analysis, was developed for identification of OA and UA in A. roxburghii. The extraction was carried out by using CO(2) as the supercritical fluid and ethanol as the modifier before LC separation. The mobile phase used for LC separation consisted of acetic acid (1%, v/v), water (15%, v/v) and methanol (84%, v/v), and the elution was performed at a flow rate of 0.8 ml/min. The mass spectrometer was operated in APCI(+) mode with selected ion monitoring (SIM) to quantify OA and UA at m/z 439.4. Under optimum conditions, the linear responses of OA and UA were obtained in the concentration range of 0.5-80 (r = 0.9992) and 0.5-50 microg/ml (r = 0.9989) with the detection limits of 0.125 and 0.085 microg/ml, respectively. The proposed method has been used for the identification and quantitation of OA and UA in a real A. roxburghii sample.
齐墩果酸（OA）和熊果酸（UA）是金线莲（Anoectochilus roxburghii (wall) Lindl）中的两种重要生物活性化合物，金线莲一直被用作传统中药。到目前为止，尚无报告表明金线莲含有这两种生物活性化合物。因此，有必要开发一种有效的方法来提取和分析金线莲中的OA和UA。本文建立了一种定量方法，该方法包括超临界流体萃取（SFE），然后进行液相色谱 - 大气压化学电离 - 离子阱质谱（LC - APCI - IT - MS）分析，用于鉴定金线莲中的OA和UA。萃取过程中以CO₂作为超临界流体，乙醇作为改性剂，然后进行液相色谱分离。用于液相色谱分离的流动相由乙酸（1%，v/v）、水（15%，v/v）和甲醇（84%，v/v）组成，洗脱流速为0.8 ml/min。质谱仪在APCI(+)模式下运行，采用选择离子监测（SIM）在m/z 439.4处对OA和UA进行定量。在最佳条件下，OA和UA在0.5 - 80 μg/ml（r = 0.9992）和0.5 - 50 μg/ml（r = 0.9989）浓度范围内呈现线性响应，检测限分别为0.125和0.085 μg/ml。所提出的方法已用于实际金线莲样品中OA和UA的鉴定和定量。
