田葱抗氧化活性组分筛选与低极性成分GC/MS分析

Screening of antioxidant active components and the GC-MS analysis of the low polar components from Philydrum lanuginosum Banks et Sol. ex Gaertner

目的筛选广西特色壮药田葱抗氧化活性组分,研究田葱低极性部位的化学成分。方法田葱乙醇粗提物浸膏分别用石油醚、乙酸乙酯和正丁醇对粗提物进行萃取得到相应有机相组分。运用酶标仪考察田葱粗浸膏和各个有机相浸膏对ABTS自由基、DPPH自由基、超氧阴离子自由基和羟自由基的清除能力,对石油醚部位成分进行气相色谱法-质谱法联用(GC-MS)分析,运用峰面积归-化法计算各成分的相对百分含量。结果田葱各萃取相均有一定的抗氧化活性,其中乙酸乙酯相抗氧化活性较好,清除ABTS、DPPH和超氧阴离子自由基的IC50值分别为697.7、742.2μg/mL和705.8μg/mL,与阳性对照维生素E的IC50值相当。GC-MS方法从田葱石油醚相中分析鉴定了41个化合物,有机酸类含量最多(53.59%)。结论田葱低极性部位主要成分为不饱和脂肪酸、萜类和甾体类,所有化合物均为首次从田葱中发现。体外抗氧化活性较好的组分主要集中于乙酸乙酯相,为田葱作为天然抗氧化剂的应用提供研究基础。

Objective To screen out the antioxidant components of Guangxi Zhuang medicine Philydrum lanuginosum Banks et Sol.ex Gaertner,and to analyze the chemical composition of the low polar components.Methods The ethanol crude extraction of Philydrum lanuginosum Banks et Sol.ex Gaertner was dispersed in water and extracted by petroleum ether,ethyl acetate and n-butanol to obtain the relative components,respectively.The antioxidant activities of the crude extraction and the organic phase extractions including ABTS,DPPH,superoxide and hydroxyl free radical scavenging ability were investigated by microplate reader.And the gas chromatography-mass spectrometry(GC-MS)was used to analyze the low polar components.The relative percentage of each component was calculated by peak area normalization.Results All the extracted phases of Philydrum lanuginosum Banks et Sol.ex Gaertner had certain antioxidant activity,among which the ethyl acetate phase had better antioxidant activity,and the IC50 values of ABTS,DPPH and superoxide radical were 697.7,742.2μg/mL and 705.8μg/mL respectively,which were similar to the IC50 values of positive control vitamin E.Forty-one compounds were identified by GC-MS from the petroleum ether phase of the field onion,with the highest organic acid content(53.59%).Conclusion The main components of the low-polarity parts of Philydrum lanuginosum Banks et Sol.ex Gaertner are unsaturated fatty acids,terpenes and steroids.All compounds are first discovered from scallions.The components with better antioxidant activity in vitro are mainly concentrated in the ethyl acetate phase,which provides a research basis for the application of Philydrum lanuginosum Banks et Sol.ex Gaertner as a natural antioxidant.