中文摘要：

应用红外光谱技术建立了一种对果胶多糖酯化度（DE）进行快速定量分析的方法。以当归果胶多糖为测试样品，采用傅里叶变换红外光谱仪（FTIR）建立了DE与A1730／（A1730＋A1630）之间的线性回归方程，相关系数为0．9852，表明果胶多糖的DE与其在1730和1630cm。处的吸收峰面积之间有良好的线性关系。经测定，从当归中提取的果胶多糖粗品和纯品的酯化度介于42．36％～54．06％之间。将FTIR法与传统的化学滴定法进行比较，两种方法间相对误差为7％，并具有良好的重现性，且与传统方法相比具有样品用量少、操作简单、快捷、灵敏度高等特点。KFIR测定果胶多糖酯化度具有可行性，可成为替代化学滴定法的一种的快速易行而准确的方法。

英文摘要：

An infrared spectroscopy method for rapid quantitative determination of the degree of esterification （DE） of pectic polysaccharides was developed. Taking pectic polysaccharides from angelica sinensis as samples, the calibration curve was established between DE and the ratio of A1 730（A1 730＋A1630 ）. The square of the linear correlation coefficient was 0. 822, indicating a good linear relationship between the DE and the absorbent area at 1 730 and 1 630 cm^-1. Using this method, the DE of pectic polysaccharides from angelica sinensis was determined to be between 42.36% and 54. 06% for crude and purified samples respectively. The relationship between infrared spectroscopy data and titrimetrically determined DE values was investigated, indicating an excellent reproducibility. This method is characterized by less sample, simple manipulation, higher sensibility, and speedy analysis compared to chemical method and other instrumentations. FTIR shows a good feasibility and can be a rapid, alternative method to titrimetrie analysis for DE determination.