荞麦籽粒乙醇提取物抗氧化成分的高效液相色谱电喷雾质谱研究

Studies on the Antioxidants of Ethanolic Extracts in Buckwheat by HPLC/ ESI-MS

【目的】研究甜荞麦和苦荞麦籽粒乙醇提取物中的主要抗氧化成分。【方法】将荞麦籽粒乙醇提取物与二苯基苦基苯肼(DPPH)自由基反应,然后用高效液相色谱仪识别乙醇提取物中的抗氧化成分,并用电喷雾质谱检测器对抗氧化成分的结构信息进行表征,以确定荞麦籽粒乙醇提取物中的抗氧成分。【结果】苦荞麦和甜荞麦籽粒乙醇提取物对DPPH自由基均有清除作用;高效液相色谱分析表明,甜荞麦和苦荞麦乙醇提取物中均含有两种主要抗氧化峰,且对应的色谱保留时间和光谱信息相同;电喷雾质谱分析表明,荞麦籽粒乙醇提取物中抗氧化成分的分子量和质谱碎裂行为分别与对照品芦丁和槲皮素的相同。【结论】采用HPLC-MS/MS法可以快速筛选荞麦籽粒提取物中的抗氧化成分,荞麦籽粒提取物中的抗氧化成分主要为芦丁和槲皮素,其中槲皮素的抗氧化活性高于芦丁。

[ Objective ] Analysis was performed to study the main antioxidants of ethanolic extracts in common buckwheat and tartary buckwheat. [Method] Buckwheat ethanol extraction subtracts with the DPPH free radicals reaction was utilized to identify the antioxidants in the extracts with HPLC, to study the structure character of antioxidation compositions by electro spray ionization-mass spectrometry （ESI-MS）, and to determine the antioxidant compositions of buckwheat ethanolic extracts. [ Result] Both the common buckwheat and the tartary buckwheat ethanolic extracts can scavenge free radical. Based on HPLC figure, two main peaks indicated two kinds of antioxidants in the extracts. Meanwhile, the corresponding chromatograph retention time was the same as from the spectrum information. The ESI-MS indicated that the molecular weights and MS fragmentation pattern of the antioxidants in the extracts were similar to the reference material of rutin and quercetin. [ Conclusion ] The method of HPLC-MS/MS can be used to screen the antioxidants in the extraction quickly.Main antioxidants of the buckwheat extracts are rutin and quercetin, while the activity of antioxidant activity of quercetin is higher than those in rutin.