两种芦笋不同部位酚类物质及抗氧化活性研究

Study of Phenolic Compounds and Antioxidant Activities in Different Part of Two Asparagus

采用超声辅助法提取白芦笋茎、白芦笋尖、绿芦笋茎和绿芦笋尖中的酚类物质,通过比色法及高效液相色谱(high performance liquid chromatography,HPLC)法测定各提取物中总酚、总黄酮、总单宁、缩合单宁和芦丁含量及其抗氧化能力(DPPH自由基、ABTS自由基清除活性和还原力),并探究芦笋酚类物质与抗氧化能力之间的相关性。结果表明,两种芦笋中均不含单宁类物质;绿芦笋尖中总酚、总黄酮、芦丁含量最高,3种抗氧化活性均最强,其后依次为绿芦笋茎、白芦笋尖和白芦笋茎。HPLC指纹图谱显示,绿芦笋尖中酚类物质的种类及含量均最高,白芦笋茎中则最少。以上结果说明绿芦笋比白芦笋中酚类物质更多,抗氧化性更强,且芦笋尖中酚类含量及抗氧化性优于芦笋茎。相关性分析发现,芦笋中总酚、总黄酮、芦丁、DPPH自由基和ABTS自由基清除能力两两之间均显著正相关,表明芦笋中酚类物质与自由基清除能力关系密切。

Phenolic compounds in white asparagus stem,white asparagus stem tip,green asparagus stem and green asparagus stem tip were extracted by ultrasonic wave.Colorimetric method and high performance liquid chromatography(HPLC)were used to determine total phenols,total flavonoids,total tannins,condensed tannins,rutin contents and their antioxidant activities(DPPH free radicals,ABTS free radicals scavenging capacities and reducing power)in the extracts of asparagus,and the correlation between these active compounds and antioxidant activities was also analyzed.The results showed that there were no tannins in both of asparagus.The total phenols,total flavonoids,rutin contents and three antioxidant activities in green asparagus stem tip were all the highest,followed by green asparagus stem,white asparagus stem tip,green asparagus stem.HPLC fingerprint showed that green asparagus stem tip displayed the highest numbers and levels of phenolic compounds,while white asparagus stem exhibited the lowest.The results above indicated that green asparagus contained more phenolic and antioxidant compounds than white asparagus,and asparagus stem tips contained more than asparagus stem.Moreover,correlation analysis showed that there was significant positive correlation between total phenol,total flavonoids,rutin,DPPH free radicals and ABTS free radicals,suggesting that the phenolic compounds in asparagus were closely related to free radical scavenging capacities.