高效液相色谱-蒸发光散射法测定油莎豆块茎发育过程中的水溶性糖

Dertermination of water-soluble sugars of Cyperus esculentus L.tubers in the growth period by HPLC-ELSD

基于高效液相色谱-蒸发光散射法(HPLC-ELSD)建立油莎豆块茎发育过程中水溶性糖(果糖、葡萄糖、蔗糖)含量的检测方法。以乙腈∶水(体积比75∶25)为流动相,流速为1.0 mL/min,并将蒸发光散射检测器条件优化为氮气压力206.8 kPa、漂移管温度65℃。结果表明:3种水溶性糖在0.10~20.0 mg/mL质量浓度范围内线性关系良好(r>0.999),检出限为0.04~0.10 g/100 g,回收率为96.0%~100.2%,相对标准偏差(RSD)为1.00%~7.32%(n=6)。在油莎豆块茎发育过程中,其果糖含量为0.376~0.692 g/100 g,葡萄糖含量为0.366~0.787 g/100 g,两者呈显著正相关(P<0.01);蔗糖含量为5.49~24.2 g/100 g,呈先降低后总体升高的趋势。所建方法灵敏度高、重现性好,适用于油莎豆块茎发育过程中水溶性糖的测定。

A detection method was established for determining water-soluble sugar(fructose,glucose,sucrose)content of Cyperus esculentus L.tubers in the growth period based on high performance liquid chromatography-evaporative light scattering detector(HPLC-ELSD).Acetonitrile:water(volume ratio 75:25)was used as the mobile phase,with a flow rate of 1.0 mL/min.The conditions of ELSD were optimized to nitrogen pressure of 206.8 kPa and drift tube temperature of 65℃.The results showed that the three water-soluble sugars had good linear relationships within the mass concentration range of 0.10-20.0 mg/mL(r>0.999),with detection limits of 0.04-0.10 g/100 g,recovery rates of 96.0%-100.2%,and relative standard deviation(RSD)of 1.00%~7.32%(n=6).For Cyperus esculentus L.tubers in the growth period,the fructose content was 0.376-0.692 g/100 g,the glucose content was 0.366-0.787 g/100 g,which showed a significant positive correlation(P<0.01).The sucrose content was 5.49-24.2 g/100 g,which showed a trend of decreasing first and then overall increasing.The established method had high sensitivity and good reproducibility,and was suitable for the determination of water-soluble sugars in Cyperus esculentus L.tubers in the growth period.