胶束毛细管电泳测定豆粕及发酵豆粕中大豆异黄酮含量

 目的 建立测定豆粕及发酵豆粕中大豆异黄酮含量的毛细管电泳方法。方法 采用胶束毛细管电泳法(MECC)，未涂层弹性石英毛细管(50 μm×60 cm，50 cm)；压力进样，压力：3.0×103 Pa；进样时间：5 s；分离电压：17 kV；柱温：20 ℃；检测波长：254 nm；运行缓冲液：15 mmol·L-1 十二烷基硫酸钠、5%甲醇的10 mmol·L-1硼砂溶液(pH 9.4)。结果 测得6种大豆异黄酮组分在24 min内能完全分离并具有良好的线性关系；平均加样回收率（n=5）在 99.6%~103.5%之间，RSD为1.8%~2.3%。结论 方法准确、可靠、经济、操作简便，适合于豆粕及发酵豆粕中大豆异黄酮含量的测定。

Determination of Soybean Isoflavones in Soybean Meal and Fermented Soybean Meal by Micella Electrokinetic Capillary Chromatography

OBJECTIVE To establish a micellar electrokinetic capillary chromatography (MECC) method for the determination of soybean isoflavones in soybean meal and fermented soybean meal. METHODS The separation was performed on a fused and uncoated silic capillary of 50 μm×60 cm (50 cm of effective length). 10 mmol·L-1 sodium borate (pH 9.4) containing 15 mmol·L-1 sodium dodecyl sulfate (SDS) and 5% methanol was used as running buffer. Samples were injected hydrodynamically (5 s, 3.0×103 Pa) into the capillary. The applied voltage was 17 kV and the wavelength of detection was set at 254 nm. The temperature was at 20 oC. RESULTS The six soybean isoflavones were completely isolated and showed good linear relationships. The average recoveries (n=5) were 99.6%-103.5% and RSDs were 1.8%-2.3% for daidzin, daidzein, genistin and genistein. CONCLUSION This method is accurate, reliable, economic, easy to operate and suitable for the determination of soybean isoflavones in soybean meal and fermented soybean meal.