基于氢核磁共振与偏最小二乘法对蛹虫草及其掺假品的鉴别

Identification of Cordyceps militaris and its adulterants based on 1H nuclear magnetic resonance and partial least square method

中文关键词:  蛹虫草  核磁共振  化学计量学  掺假检测

英文关键词:Cordyceps militaris  nuclear magnetic resonance  chemometrics  adulteration detection

中文摘要:

      目的 采用氢核磁共振(1H nuclear magnetic resonance, 1H NMR)结合正交偏最小二乘法(orthogonal partial least squares, OPLS)建立对蛹虫草中金针菇、杏鲍菇和香菇掺假的鉴别方法。方法 主成分分析得分图显示, 不同类型的掺假样品并不能完全分离。采用两步法进一步提高模型的鉴别能力, 首先对纯蛹虫草和掺假蛹虫草进行正交偏最小二乘判别分析(orthogonal partial least squares discriminant analysis, OPLS-DA), 模型显示真假蛹虫草分类良好, 两类样品存在明显区别。然后对所有20%掺假蛹虫草进行双向正交偏最小二乘判别分析(two-way orthogonal partial least squares discriminant analysis, O2PLS-DA), 通过分别由28个和12个样本组成的训练和测试集来检查鉴别能力的准确性。结果 掺假物金针菇、杏鲍菇和香菇能够被准确辨别。结论 1H NMR代谢指纹图谱结合化学计量学, 对于真伪蛹虫草及掺假类型能够有效鉴别, 具有商业筛选的应用前景。

英文摘要:

      Objective To establish an identification method for adulterated Flammulina velutipes, Pleurotus eryngii, and Lentinus edodes in Cordyceps militaris using 1H nuclear magnetic resonance (1H NMR) combined with orthogonal partial least squares (OPLS) method. Methods The score chart of principal component analysis showed that different types of adulterated samples could not be completely separated. The two-step method was used to further improve the identification ability of the model. Firstly, orthogonal partial least squares discriminant analysis (OPLS-DA) was performed on pure and adulterated Cordyceps militaris. The model showed that the classification of true and adulterated Cordyceps militaris was good, and there were significant differences between the two types of samples. Then, two-way orthogonal partial least squares discriminant analysis (O2PLS-DA) model analysis was performed on all 20% adulterated Cordyceps militaris, and the accuracy of the discrimination ability was checked through training and testing sets consisting of 28 and 12 samples, respectively. Results The adulterated Flammulina velutipes, Pleurotus eryngii, and Lentinus edodes could be accurately identified. Conclusion The combination of 1H NMR metabolic fingerprint and chemometrics can effectively identify the authenticity and adulteration types of Cordyceps militaris, so this method has the application prospect of commercial screening.