Purple yam (Dioscorea alata L) has been extensively investigated in the fields of biomedicine, pharmacology, and toxicology. As functional components, phenolic compounds exhibit high levels of biological activities. In this study, seven phenolic compounds extracted from Chinese purple yam were successfully identified using high-performance liquid chromatography combined with high-resolution electrospray ionization mass spectrometry. Comparison of the retention time and mass spectra of the extracted compounds with those of authentic standards confirmed the existence of ferulic acid (4) and sinapic acid (5). And five kinds of the previously unidentified phenolic compounds were revealed, including one kind of dihydroxybenzoic acid (vanillic acid, 2), two sets of hydroxycinnamic acids (caffeic acid, 1 and p-coumaric acid, 3), and two kinds of anthocyanins (quercetin dehydrate, 6 and kaempferol, 7). In addition, the total antioxidant activity and DPPH free radical scavenging activity of the isolated fractions were evaluated, and the concentrated F₁ fraction displayed a high total antioxidant activity (2.38 mM) and DPPH free radical scavenging activity (89.56%). This study provided an in-depth insight into the diversified components and antioxidant activity of purple yam. Such information is beneficial to the post processing and storage of purple yam products.

紫薯（Dioscorea alata L）已经在生物医学，药理学和毒理学领域进行了广泛的研究。作为功​​能成分，酚类化合物表现出高水平的生物活性。在这项研究中，使用高效液相色谱结合高分辨率电喷雾电离质谱法成功地鉴定了从紫心山药中提取的7种酚类化合物。提取的化合物与真实标准品的保留时间和质谱的比较证实了阿魏酸（4）和芥子酸（5）的存在。并发现了五种先前无法确定的酚类化合物，包括一种二羟基苯甲酸（香草酸，2），两组羟基肉桂酸（咖啡酸1和对香豆酸3）和两种花色苷（脱水槲皮素6和山奈酚7）。另外，评估了分离的级分的总抗氧化剂活性和DPPH清除自由基活性，并且浓缩的F ₁级分显示出高的总抗氧化剂活性（2.38mM）和DPPH清除自由基活性（89.56％）。这项研究对紫山药的多种成分和抗氧化活性提供了深入的了解。这样的信息对于紫色山药产品的后期处理和存储是有益的。