反相高效液相法测定甜叶菊中莱鲍迪苷A和甜菊糖苷的含量

目的建立反相高效液相色谱法（RP．HPLC）测定甜叶菊中莱鲍迪苷A（RA）和甜菊糖苷（ST）的含量。方法采用welchMaterials XB—C18柱（250mm×4．6mm，5μm），以乙腈．10mmol·L^-1磷酸酸钠缓冲液（pH=2．67，35：65，v～）为流动相，流速0．7mL·min^-1，检测波长210nm，柱温30℃，进样量5此。结果以外标法定量，RA和sT均在O．25～2．50mg·mL^-1与峰面积线性关系良好，r〉0．9995。RA回收率为100．3％，RSD为2．3％（n=6），ST回收率为101．0％，RSD为2．5％（n=6）。结论本方法快捷、准确、可靠，易操作，可用于甜叶菊及相关产品中RA和ST含量测定。

Determination of rebaudioside A and stevioside in leaves of Stevia rebaudiana by RP-HPLC

Objective To establish a method for the determination of rebaudioside A （RA） and stevioside （ST） in leaves of Stevia rebaudiana by RP-HPLC. Methods The chromatographic separation was used with a Welch Materials C18 column （4.6 mm× 250 mm, 5 μm）. The mobile phase was composed of acetonitrile and 10 mmol. L^ - 1 phosphate sodium acetate buffer （35 ： 65, v/v, the pH adjusted to 2.67 with phosphoric acid）, the flow rate was 0.7 mL . min^- 1and the detection wavelength was set at 210 nm. The sample injection volume was 5μL and the temperature of column was 30 ℃ . Results Both RA and ST showed a good linear relationship （r 〉 0.999 5） at 0.25 -- 2.50 mg . mL^ -1 and the recovery of RA and ST was 100.3% and 100.7%, respectively. Conclusion RP-HPLC method is simple, sensitive and reliable for the determination of RA and ST in stevia rebaudiana and related products.