楸树叶中抗氧化活性成分的分离和鉴定

Isolation and Identification of Bioactive Compounds with Antioxidant from Catalpa bungei

前期研究发现,楸树叶粗提物的乙酸乙酯萃取相具有较强的抗氧化活性。为了进一步明确其抗氧化活性成分,以硅胶柱色谱结合清除DPPH自由基法,寻找抗氧化能力较强的组分,并利用半制备液相色谱对该组分进行分离、纯化,以清除DPPH自由基、还原力和清除ABTS自由基能力作为考察指标,根据理化性质及光谱数据鉴定化合物。结果从楸树叶粗提物的乙酸乙酯萃取相中分离得到了2个化合物,分别为木犀草素(1)和芹菜素(2)。化合物1的抗氧化活性强于BHT和化合物2;化合物1清除DPPH自由基、还原力及清除ABTS自由基的IC50值分别为23.89,29.77和43.47μg!mL-1;化合物1的抗氧化活性强于化合物2,主要因其在黄酮类化合物母核的B环上具有邻二酚羟基结构。木犀草素和芹菜素2个化合物首次从楸树叶中分离得到。

Our previous study found that ethyl acetate extract phase of Catalpa bungei leaves had strong antioxidant activity. In order to further clarify its antioxidant activity,we have searched the components had strong antioxidant ability though silica gel column chromatography combined with DPPH free radical scavenging methods. The antioxidant components were isolated and purified by semi preparative liquid chromatography. With DPPH radical scavenging activity, reducing capacity and ABTS radical scavenging activity ability as investigation index to find the antioxidant components and the physicochemical properties and spectral data were to identify compounds. The results showed that the ethyl acetate extract phase of C. bungei leaves had two compounds： luteolin （ 1 ） and apigenin （ 2 ） . The antioxidant activity of compound 1 was stronger than BHT and compound 2. DPPH radical scavenging activity,reducing power and ABTS radical scavenging activity IC50 values of compound 1 were 23. 89,29. 77 and 43. 47 μg＆#183;mL -1 respectively. The antioxidant activity of compound 1 was stronger than compound 2 mainly because of its adjacent structure of two phenolic hydroxyl groups in the flavone compound nucleus of B ring. Luteolin and apigenin isolated from C. bungei leaves for the first time.