采用红外光谱、二阶导数红外光谱以及二维相关红外光谱,对七种不同产地的仙鹤草原药材及其总鞣酸提取物进行了鉴别分析。仙鹤草原药材的红外光谱中出现了1 151,1 101,1 032 cm-1的淀粉特征峰,同时还出现了1 618,1 318,780 cm-1的草酸钙特征峰,说明在原药材粉末中同时有淀粉和草酸钙存在。原药材丙酮提取物中所含淀粉等基本成分大为减少,而总鞣酸等有效成分的相对含量增加,因此不同产地仙鹤草丙酮提取物的红外光谱中均出现1 711与1 447 cm-1的鞣酸特征峰。应用红外光谱、二阶导数红外光谱以及二维相关红外光谱技术,不仅可以提供仙鹤草主要化学成分的相关信息,还可以对不同产地的仙鹤草药材进行很好的区分。因此红外光谱法是考察中药资源的一种快速、准确、有效的方法。
The objective of the present study is to discriminate seven species of Agrimonia pilosa Ledeb herbs and their total tannin extracts by Fourier transform infrared spectroscopy(FTIR),second derivative infrared spectroscopy,and two-dimensional correlation infrared spectroscopy(2D-IR) under thermal perturbation.The structural information of the samples indicated that Agrimonia pilosa Ledeb and their extract residues contain a large amount of starch and calcium oxalate,since some characteristic absorption peaks of the starch,such as 1 151,1 101,1 032 and 988 cm-1 can be observed;and some characteristic absorption peaks of the calcium oxalate,such as 1 618,1 318 and 780 cm-1,can be observed.Further more,the characteristic absorption peaks of the sulfate which arouse at 1 711 and 1 447 cm-1 in the IR spectra of Agrimonia pilosa Ledeb acetone extracts can be found.The macroscopical fingerprint characters of FTIR and 2D-IR spectra can not only provide the information of main chemical constituents in medicinal materials and their different extracts,but also compare the components differences among the similar samples.In conclusion,the multi-steps IR macro-fingerprint method is rapid,effective,visual and accurate for pharmaceutical research.