金钗石斛及其提取物的红外光谱整体解析

Integral analysis of Dendrobium nobile and its extracts by infrared spectroscopy

[目的]采用红外光谱技术对金钗石斛原药材及两种提取物所含化学成分的红外谱图进行整体分析。[方法]采用傅里叶红外光谱法对金钗石斛原药材、水提醇沉提取物、无水乙醇提取物进行结构分析及鉴别。[结果]金钗石斛原药材一维红外光谱图反映出2 923 cm^(-1)、2 855 cm^(-1)、1 738 cm^(-1)、1 155 cm^(-1)、1 081 cm^(-1)、1 019 cm^(-1)等特征峰,推测金钗石斛中含有脂类、芳香类和淀粉类成分。原药材二阶导数谱分析进一步验证了以上结果,同时出现了1 318 cm^(-1)附近以及783 cm^(-1)附近的草酸钙吸收峰。金钗石斛水提醇沉提取物和无水乙醇提取物的红外谱图中均出现了脂类、芳香类和糖类的特征峰,且与原药材相比峰数、峰强都有改变。金钗石斛水提醇沉物一维和二阶导数谱中均出现了较强的淀粉特征峰,说明水提物中主要是水溶性多糖,且多糖主要以淀粉形式存在。而无水乙醇提取物谱图更清楚的出现了脂类和芳香类的相关特征峰,且峰数与峰形和油类标准品比对,重叠性高。[结论]金钗石斛中主要含有多糖类以及脂肪类物质,多糖主要是以淀粉存在,且金钗石斛中的脂肪类含量较高。不同的提取溶剂所出现的谱图存在很大的差异性,完美诠释了"相似相溶"原则。红外光谱适合于金钗石斛的快速鉴别及质量评价与控制。

[Objective] Infrared spectroscopy was used to analyze the infrared spectra of the original medicinal materials of Dendrobium nobile and the chemical constituents contained in the two extracts. [Methods] Fourier transform infrared spectroscopy（FTIR） was used to analyze the structure of the Dendrobium nobile and the extracts of Dendrobium nobile. [Results] In the one-dimensional spectrum of Dendrobium nobile, the characteristic peaks of 2 923 cm^-1, 2 855 cm^-1, 1 738 cm^-1, 1 155 cm^-1, 1 081 cm^-1, 1 019 cm^-1 and so on can be seen. It is presumed that Dendrobium nobile contains lipids, aromatic and starches. The results of the second derivative of the original medicinal materials further confirmed the above results, while the strong peaks near 1 318 cm^-1 and the characteristic peaks near 783 cm^-1 appeared, and compared with the standard, it was determined to contain calcium oxalate. The peak of lipids, Aromatic and starches all appeared in the infrared spectra of extracts, but the number and the strength of peak were different. The strong characteristic peaks of starch were found in the one-dimensional and second-order derivative spectra of Dendrobium nobile, indicating that the compositions of water extract were mainly water-soluble polysaccharides, and the polysaccharides mainly existed in starch form. While the spectrum of ethanol extract was more clearly showing the correlation peaks of lipids and aromatics, and the number of peak and the shape of peak compared with oil standard, which has high overlap. [Conclusion] Dendrobium nobile contains polysaccharides and fatty substances.Polysaccharides mainly contain starch, and the content of fat in Dendrobium nobile is higher. Different extraction solvents appear in the spectrum there is a big difference, the perfect interpretation of the ＂similar compatibility＂ principle. Infrared spectroscopy provides a good method for the overall structure analysis and identification of Dendrobium nobile and quality control.