高效阴离子交换色谱-脉冲安培法测定蔬菜及食品中的1-蔗果三糖和蔗果四糖

目的应用高效阴离子交换色谱-脉冲安培检测器联用(HPAEC-PAD)技术,建立蔬菜、食品中低聚果糖(蔗果三糖和蔗果四糖)检测方法。方法以NaOH和乙酸钠为淋洗液梯度淋洗,在CarboPac PA1色谱柱上阴离子交换分离了蔗果三糖和蔗果四糖,用脉冲安培检测器(金电极)进行了检测。结果二者的线性范围分别为1.22~15.20μg/g和1.64~18.30μg/g,检出限分别为0.085μg/g和0.089μg/g。对浓度为6.08和7.32μg/g的蔗果三糖和蔗果四糖混合标准连续进样,其相对标准偏差(RSD)分别为2.80%和1.28%(n=6)。应用本方法分析了菊苣、朝鲜蓟和通力爽口服液等蔬菜和食品中蔗果三糖和蔗果四糖的含量。蔗果三糖和蔗果四糖含量最高的蔬菜组织为菊苣根,分别为6.61g/100g干重和6.51g/100g干重。低聚果糖粉中蔗果三糖和蔗果四糖含量最高,分别为34.13g/100g和32.12g/100g。样品加标回收率蔗果三糖和蔗果四糖分别为93.97%和97.14%。结论该方法简单、方便、灵敏度高,适于蔬菜及食品中蔗果三糖和蔗果四糖的测定。

Determination of 1-kestose and nystose in vegetables and food products by high performance anion exchange chromatography coupled with pulsed amperometric detection

Objective A methods for the simultaneous determination for 1-kestose(GF_2) and nystose(GF_3) in foods and vegetables by high performance anion exchange chromatography with integrated pulsed amperometric detection(HPAEC-PAD) was developed in this study.Methods With a gradient program,and NaOH and sodium acetate as mobile phase,the two fructo-oligosaccharides(FOS) were separated on a CarboPac PA1 column and then detected by a gold electrode.Results The linear range were 1.22-15.20μg/g and 1.64-18.30μg/g for GF_2 and GF_3,and the calculated method detection limit(MDL) were 0.085μg/g and 0.089μg/g,respectively.The relative standard deviation of GF_2(6.08μg/g) and GF_3(7.32 μg/g) were 2.80% and 1.68%(n=6).The contents of the two fructo-oligosaccharides in chicory root, artichoke and oral liquid were also determined.The results shows chicory root possess the highest GF_2 and GF_3 contents in all vegetable tissues,6.61g/100g dw and 6.51g/100g dw,whereas the highest composition of kestose and nystose in food was found in Quantum FOS powder(raw material for additives),34.13g/100g and 32.12g/100g respectively.The method recoveries of GF_2 and GF_3 were 93.97% and 97.14 %.Conclusion This method was sensitive,selective,and simple for FOS quantification in vegetables and food products.