State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.
J Pharm Biomed Anal. 2013 Nov;85:231-8. doi: 10.1016/j.jpba.2013.07.034. Epub 2013 Aug 7.
Traditional Chinese medicines (TCM) can be identified by experts according to their odors. However, the identification of these medicines is subjective and requires long-term experience. In this paper, electronic nose, headspace gas chromatography-mass spectrometry (GC-MS) and chemometrics methods were applied to differentiate two species of Asari Radix et Rhizoma by their odors. The samples used were the dried roots and rhizomes of Asarum heterotropoides var. mandshuricum (AH) and Asarum sieboldii (AS). The electronic nose was used to determine the odors of the samples and enabled rapid differentiation of AH and AS when coupled with principal component analysis. Headspace GC-MS was utilized to reveal the differences between the volatile constituents of AH and AS. In all, 54 volatile constituents were identified, and 9 major constituents (eucalyptol, eucarvone, 3,5-dimethoxytoluene, 3,4,5-trimethoxytoluene, methyleugenol, 2,3,5-trimethoxytoluene, croweacin, pentadecane and asaricin) could be used as chemical markers to distinguish these two species. AH contained higher relative contents of eucarvone (1.79-16.76%), 3,5-dimethoxytoluene (6.64-26.52%), 3,4,5-trimethoxytoluene/methyleugenol (6.43-31.67%) and 2,3,5-trimethoxytoluene (1.64-6.66%), whereas AS had higher relative contents of eucalyptol (14.06-24.95%), croweacin (5.64-13.55%), pentadecane (8.44-20.82%) and asaricin (7.03-13.45%). Moreover, AH and AS could be distinguished according to the contents of either all 54 identified volatile constituents or only the 9 major constituents by employing cluster analysis. The proposed method is rapid, simple, eco-friendly and can successfully differentiate these two species of Asari Radix et Rhizoma by their odors.
传统中药（TCM）可以通过专家根据其气味来识别。然而，这些药物的识别是主观的，需要长期的经验。本文采用电子鼻、顶空气相色谱-质谱联用（GC-MS）和化学计量学方法，通过气味区分两种细辛根和根茎。所用样品为北细辛（AH）和辽细辛（AS）的干根和根茎。电子鼻用于确定样品的气味，与主成分分析相结合时，能够快速区分 AH 和 AS。顶空 GC-MS 用于揭示 AH 和 AS 挥发性成分之间的差异。总共鉴定出 54 种挥发性成分，其中 9 种主要成分（桉油精、爱草脑、3,5-二甲氧基甲苯、3,4,5-三甲氧基甲苯、甲基丁香酚、2,3,5-三甲氧基甲苯、克罗威酸、十五烷和细辛脂素）可作为化学标志物来区分这两个种。AH 中爱草脑（1.79-16.76%）、3,5-二甲氧基甲苯（6.64-26.52%）、3,4,5-三甲氧基甲苯/甲基丁香酚（6.43-31.67%）和 2,3,5-三甲氧基甲苯（1.64-6.66%）的相对含量较高，而 AS 中桉油精（14.06-24.95%）、克罗威酸（5.64-13.55%）、十五烷（8.44-20.82%）和细辛脂素（7.03-13.45%）的相对含量较高。此外，通过聚类分析，采用 54 种鉴定出的挥发性成分或仅采用 9 种主要成分的含量，均可区分 AH 和 AS。该方法快速、简单、环保，可成功区分这两种细辛根和根茎。
