College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Central South University, Changsha 410083, PR China.
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China.
Food Chem. 2019 Aug 1;288:215-220. doi: 10.1016/j.foodchem.2019.03.013. Epub 2019 Mar 7.
Du-zhong brick tea (DBT), a new post-fermented functional tea, is marketed in China for its prevention of diseases from oxidative stress. However, antioxidant compounds in DBT are not clear. Here, a novel online extraction-HPLC-ferric reducing antioxidant power (OLE-HPLC-FRAP) has been developed to screen antioxidants in DBT. For OLE, guard column is packed with DBT (1.0 mg), then compounds are extracted directly by HPLC mobile phase for HPLC-FRAP analysis without sample pretreatment procedures. Eleven antioxidants have been screened and identified, three of which are detected in Du-zhong for the first time. Contributions of eleven antioxidant compounds to total antioxidant activity are evaluated using chlorogenic acid as antioxidant marker. Results indicate that the developed OLE-HPLC-FRAP system is a simple and powerful tool to analyze antioxidant compounds from solid complex mixtures, which also contribute to the enhancement of the value of DBT as a good functional tea.
都中砖茶（DBT）是一种新型的后发酵功能茶，在中国市场上因其预防氧化应激相关疾病而受到欢迎。然而，DBT 中的抗氧化化合物尚不清楚。本研究建立了一种新型的在线提取-高效液相色谱-铁还原抗氧化能力（OLE-HPLC-FRAP）方法，用于筛选 DBT 中的抗氧化剂。对于 OLE，保护柱中填充 1.0mg 的 DBT，然后直接用 HPLC 流动相提取化合物，无需样品预处理程序，即可进行 HPLC-FRAP 分析。共筛选并鉴定了 11 种抗氧化剂，其中 3 种是首次在都中检测到的。以绿原酸作为抗氧化剂标志物，评估了 11 种抗氧化化合物对总抗氧化活性的贡献。结果表明，所建立的 OLE-HPLC-FRAP 系统是一种从固体复杂混合物中分析抗氧化化合物的简单而强大的工具，这也有助于提高 DBT 作为一种良好的功能性茶的价值。
