草乌类蒙药的红外光谱分析与鉴定

Analysis of Different Parts of Aconitum kusnezoffii Reichb. Using Fourier Transform Infrared Spectroscopy

目的:对蒙药草乌根、草乌叶、草乌花、草乌芽的原药材及其总生物碱提取物进行分析。方法:采用红外光谱的三级鉴定方法(红外光谱、二阶导数谱以及二维相关谱)进行样品的全成分分析。结果:草乌根的谱图与淀粉的标准谱图相似,出现淀粉特征峰1 155、1 070、1 019 cm^(-1),故草乌根含有大量淀粉;叶、花、芽含芳香类物质较多(1 600 cm^(-1)),糖苷类物质(1 050-1 070 cm^(-1))、酯类物质不明显;草乌花、草乌叶、草乌芽的红外谱图中能够观察到芳香环(1 595 cm^(-1)附近)和=C-O(1 262 cm^(-1)附近)有特征吸收,证明三者共有成分为二萜类生物碱。二阶导数谱图显示,根在1 712 cm^(-1)(C=O)附近的特征峰明显强于花、叶和芽,说明根中二萜类生物碱类成分含量高于花、叶和芽;二维谱图在800-1 300 cm^(-1)处根有6个自动峰1 745、1 650、1 560(最强)、1 465、1400、1300 cm^(-1);叶、芽、花相似其自动峰有1680、1560(最强)、1465 cm^(-1)。结论:红外光谱宏观指纹技术可提供大量整体信息,能够较准确的把握草乌类药材的整体质量。红外光谱法和二维相关光谱提供了大量草乌、草乌花、草乌叶、草乌芽的整体结构信息,验证了4种药材所含物质结构和含量的差异,为今后草乌的系统研究工作奠定基础。

The radix, leaf, flower and bud of raw medicinal materials and extraction of total alkaloids of Aconitum kusnezoffii Reichb. were all involved in this investigation. All the compositions from the samples were analyzed through fourier transform infrared spectroscopy（FTIR） combined with second derivative IR spectroscopy and two-dimensional IR correlation spectroscopy（2D-IR）. It was found that the spectra of raw medicinal materials showed that the radix of A. kusnezoffii Reichb. featuring a large quantity of starch was the same as starch with the characteristic peaks at 1,155, 1,070 and 1,019. The leaf, flower and bud contained the similar aromatic hydrocarbons（1,600）, glycosides（1,050-1,070）, while lipids were not clear. The characteristic peaks of the buds, flowers and leaves were all at 1,595 cm^-1（vibration of phenyl framework） and 1,262 cm^-1（=C-O）. Therefore, it was suggested that the common compound of the three parts be diterpenoid alkaloids. Second derivative IR spectroscopy showed that the characteristic peaks of radix was stronger than those of the flower, leaf and bud at 1,712 cm^-1（C=O）, which proved that the quantity of characteristic peaks in the radix was larger than those in the flower, leaf and bud. In addition, six autopeaks at 1,745, 1,650, 1,560（the most strong）, 1,465, 1,400, 1,300 were detected from the radix. The similar autopeaks at 1,745, 1,650, 1,560（the most strong）, 1,465, 1,400, 1,300 were found in the leaf, bud and flower. In conclusion, it was demonstrated that the macro-fingerprint infrared spectroscopic identification method provided a large quantity of the comprehensive information and entirely grasped the quality of A. kusnezoffii Reichb. Besides, FTIR and 2D-IR provided massive information of the integral structures of the radix, leaf, flower and bud of A. kusnezoffii Reichb. and verified the differences between the four parts of the herb in physical structure and the contents, laying a foundation for further systematic work.