中文摘要：

建立高效液相色谱分别测定结冷胶中乙酰基和甘油酰基含量的方法。通过水解方法将酰基从结冷胶分子中游离出来,酸化为乙酸和甘油酸（或酸根离子）,醇沉将结冷胶除去,高效液相色谱检测有机酸的含量,再根据有机酸与相应酰基的分子质量关系,用内标法,并以丙酸作为内标物,计算得到2种酰基的含量。使用HPX-87H色谱柱,以5mmol/L硫酸溶液作为流动相,在柱温35℃,流速0.6mL/min条件下,利用紫外检测器进行检测,检测波长210nm。结果表明,此方法可同时定量2种目的物,20min内可完成测定,且灵敏度高,重复性和稳定性良好。实验测得本实验室生产的结冷胶中甘油酰基和乙酰基的质量分数分别为9.94%、3.29%,甘油酰基加标回收率为97.76%,相对标准偏差为0.59%,乙酰基加标回收率为93.49%,相对标准偏差为1.29%。

英文摘要：

A method to measure the contents of glyceoyl and acetyl in gellan with high performance liquid chromatography （HPLC） was established. Acyl groups were dissociated from gellan by hydrolization and acidized to obtain acetic acid and glyceric acid. Then alcohol precipitation was used to remove the gel and the contents of the two kinds of organic acids were assayed by HPLC. The contents of the two acyl groups were calculated according to the corresponding relationship in molecular weight between the acyl groups and organic acids, using propionic acid as the internal standard substance. The chromatographic column used was HPX-87H with 5 mmol/L sufuric acid as the mobile phase at a flow rate of 0.6 mL/min. The column temperature was maintained at 35 ℃, and the analytes were detected at a UV wavelength of 210 nm. The method could quantify these two organic acids simultaneously within 20 min. It is an efficient method with excellent repeatability and stability. The contents of glyceroyl and acetyl of gellan produced in our laboratory were 9.94% and 3.29%with spiked recoveries of 97.76% and 93.49%, respectively.