芹菜素席夫碱金属配合物的合成及抗氧化活性研究

Synthesis of Schiff Base Metal Derivatives of Apigenin and Their Antioxidant Activity

摘要:

芹菜素(AP)是一种天然的抗氧化剂，具有多种生物活性，但是存在药效低、开发利用低等问题。为了提高芹菜素的开发应用和药效，本研究对芹菜素进行结构修饰，制备了芹菜素席夫碱金属衍生物，并采用紫外（UV），红外（UV），差热－热重分析（DSC-DTG）等波谱分析方法表征化合物。采用水杨酸法和邻苯三酚-NBT法评价芹菜素和其衍生物的体外清除羟基自由基（?OH）和超氧自由基（O2-?）活性。通过表征，合成了两种新的芹菜素席夫碱金属配合物，即[Co(C22H16O4N)2(H2O)2]?8H2O和[Zn(C22H16O4N)2(H2O)2]?4H2O配合物，AP、[CoL2]和[ZnL2]清除?OH自由基的IC50为880.65±46.52 μg/mL，517.12±16.36 μg/mL，633.62±18.95 μg/mL；清除O2-?自由基的IC50为116.30±3.94 μg/mL，61.13±0.05 μg/mL，48.56±0.32 μg/mL，合成的配合物相对芹菜素抗氧化活性增强，有望开发出一种新型抗氧化性食品添加剂，为芹菜素的开发及抗氧化剂的研究提供理论研究基础。

Abstract:

Apigenin (AP) is a natural antioxidant possessing multiple biological activities, but has some limitations such as low efficacy and low utilization. To better develop and utilize AP, its structure was modified. The Schiff-base derivatives of AP ([Co(C22H16O4N)2(H2O)2]?8H2O and [Zn(C22H16O4N)2(H2O)2]?4H2O) were synthesized, and characterized by ultraviolet (UV), infrared (IR), differential scanning calorimetry (DSC)-derivative thermograms (DTG), and other spectroscopic methods. Through the salicylic acid method and the pyrogallic acid-nitroblue tetrazolium (NBT) method, the in vitro superoxide radical and hydroxyl radical scavenging activities of AP and its Schiff-base derivatives were evaluated. Structural characterization showed that two Schiff-base derivatives of AP, [Co(C22H16O4N)2(H2O)2]?8H2O and [Zn(C22H16O4N)2(H2O)2]?4H2O, were successfully prepared. The half-maximal inhibitory concentration (IC50) values of AP, [CoL2], and [ZnL2] on scavenging hydroxyl radical were 880.65 ± 46.52 μg/mL, 517.12 ± 16.36 μg/mL, and 633.62 ± 18.95 μg/mL, respectively. The IC50 values of AP, [CoL2], and [ZnL2] on scavenging superoxide radical were 116.30 ± 3.94 μg/mL, 61.13 ± 0.05 μg/mL, and 48.56 ± 0.32 μg/mL, respectively. Two novel Schiff-base complexes of AP, [Co(C22H16O4N)2(H2O)2]?8H2O and [Zn(C22H16O4N)2(H2O)2]?4H2O, possessed stronger antioxidant activity than AP, which might be a new antioxidant food additive. This research provided a theoretical basis for AP development during future studies on antioxidants.