Cereal Institute, National Agricultural Research Foundation, Thessaloniki, Greece.
J Sep Sci. 2011 Jun;34(12):1375-82. doi: 10.1002/jssc.201100077. Epub 2011 Apr 20.
The increasing interest in antioxidant properties of cereal and cereal-based products has prompted the development of a simple and reliable HPLC method for the simultaneous determination of important phytochemicals like tocopherols (T), tocotrienols (T3) and carotenoids. Separation was carried out on a Nucleosil 100 C(18) column, 5 μm (250 mm × 4.6 mm) thermostated at 25 °C, using a linear gradient elution system starting with methanol and ending with a mixture of methanol-isopropanol-acetonitrile. All separated compounds including the internal standard (α-tocopherol acetate) were eluted within 16 min and detected by dual detection: fluorescence for tocopherols and tocotrienols at 290 nm excitation and 320 nm emission and UV-vis photodiode array detection for lutein and β-carotene at 450 nm. Detection limits ranged from 0.2 μg/g (β-carotene) to 1.60 μg/g (α-tocopherol). The intra- and inter-assay coefficients of variation were calculated by using cereals with different levels of lipophilic antioxidants. The extraction method involved sample saponification and clean-up by solid-phase extraction (SPE). The extraction recoveries obtained using OASIS HLB SPE cartridges and dichloromethane as eluent were in the range of 90.2-110.1%, with RSD lower than 10%. The method was successfully applied to cereals: durum wheat, bread wheat, rice, barley, oat, rye, corn and triticale.
谷物及其制品的抗氧化特性日益受到关注，这促使人们开发出一种简单可靠的 HPLC 方法，用于同时测定生育酚（T）、三烯生育酚（T3）和类胡萝卜素等重要植物化学物质。分离在 Nucleosil 100 C(18)柱上进行，5 μm（250 mm×4.6 mm），在 25°C 下恒温，使用甲醇起始的线性梯度洗脱系统，最终为甲醇-异丙醇-乙腈混合物。所有分离的化合物，包括内标（醋酸生育酚），在 16 分钟内洗脱，并通过双检测进行检测：荧光检测生育酚和三烯生育酚在 290nm 激发和 320nm 发射，紫外可见光电二极管阵列检测叶黄素和β-胡萝卜素在 450nm。检测限范围为 0.2μg/g（β-胡萝卜素）至 1.60μg/g（α-生育酚）。使用不同脂溶性抗氧化剂水平的谷物计算了日内和日间变异系数。提取方法涉及样品皂化和固相萃取（SPE）净化。使用 OASIS HLB SPE 小柱和二氯甲烷作为洗脱剂，提取回收率在 90.2-110.1%之间，RSD 低于 10%。该方法成功应用于谷物：硬粒小麦、面包小麦、大米、大麦、燕麦、黑麦、玉米和小黑麦。
