枣花蜜酚类化合物组成及其抗氧化活性分析

以陕西佳县、府谷、大荔、渭南4 个地区枣花蜜为研究对象，测定其理化指标、酚类化合物含量、体外抗氧化活性、对·OH诱导的pBR322质粒DNA氧化损伤的保护作用及过氧化氢（H2O2）诱导的小鼠淋巴细胞DNA氧化损伤的保护作用。结果表明，枣花蜜总酚含量为196.55～454.95 mg/kg，总黄酮含量为22.03～39.40 mg/kg；高效液相色谱-电喷雾-四极杆-飞行时间串联质谱分析发现枣花蜜中含有15 种酚类化合物，包括4 种酚酸和11 种黄酮类化合物；体外抗氧化实验表明，枣花蜜具有较强的1,1-二苯基-2-三硝基苯肼自由基清除能力（半抑制浓度为38.03～122.81 mg/mL）、Fe2＋络合能力（110.93～158.46 mg/kg）和Fe3＋还原力（166.68～365.06 mg/kg）；此外，枣花蜜对·OH诱导的pBR322质粒DNA氧化损伤有保护作用且能显著降低H2O2诱导的小鼠淋巴细胞DNA氧化损伤。本实验的研究结果可为枣花蜜资源的开发利用提供理论参考。

Phenolic Compounds and Antioxidant Activity of Jujube Honey

In this study,the physicochemical properties,phenolic content,and antioxidant activity in vitro of jujube honeys collected from four regions of Shaanxi province:Jiaxian,Fugu,Dali and Weinan were investigated as well as their effect in protecting plasmid pBR322 against hydroxyl radical-induced oxidative DNA damage and protecting mouse lymphocytes against oxidative DNA damage induced by hydrogen peroxide(H2O2).The results showed that the jujube honeys contained 196.55–454.95 mg/kg of total phenolics,and 22.03–39.40 mg/kg of total flavonoids.By high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry(HPLC/ESI-QTOF-MS),a total of 15 phenolic compounds were detected in the samples,including four phenolic acids and 11 flavonoids.In vitro antioxidant test indicated that the jujube honeys had strong 1,1-diphenyl-2-trinitrophenylhydrazine(DPPH)radical scavenging capacity with a half maximal inhibitory concentration(IC50)of 38.03–122.81 mg/mL,ferrous ion chelating activity(110.93–158.45 mg/kg),and ferric reducing power(166.68–365.06 mg/kg).Furthermore,the jujube honeys had a protective effect against oxidative DNA damage in plasmid pBR322 induced by hydroxyl radical and could significantly reduce oxidative DNA damage induced by H2O2 in mouse lymphocytes.The present study provides a theoretical basis for the development and utilization of jujube honey resources.