Bioorganic Laboratory, Department of Chemistry, University of Delhi, Delhi-110007, India.
Nat Prod Res. 2012;26(18):1682-6. doi: 10.1080/14786419.2011.592836. Epub 2011 Oct 10.
An activity-guided isolation and purification process was used to identify the DPPH (l,l-diphenyl-2-picrylhydrazyl) radical-scavenging components of Swertia chirayita. A dry, whole plant of S. chirayita was extracted with different solvents and tested for its DPPH radical-scavenging activity. The acetone : water (8 : 2) extract showed the highest total phenolic content (TPC) and DPPH radical-scavenging activity, which was column chromatographed to obtain decussatin, swertianin, bellidifolin, isobellidifolin, amarogentin, swertianolin and mangiferin as active components. Good correlation was observed between TPC and DPPH scavenging activity among the extracts. The unique structure of xanthones, including the catecholic moiety and the completely conjugated system, enables them to be promising antioxidants.
采用活性导向分离纯化方法，从獐牙菜中鉴定出具有清除 DPPH（l,l-二苯基-2-苦基肼基）自由基活性的成分。干燥的獐牙菜全草用不同溶剂提取，并测试其清除 DPPH 自由基的活性。丙酮：水（8：2）提取物表现出最高的总酚含量（TPC）和清除 DPPH 自由基的活性，然后对其进行柱层析，得到裂环獐牙菜苦苷、当药苦苷、獐牙菜苦苷、异当药苦苷、当药苷、当药宁和芒果苷作为活性成分。提取物的 TPC 与清除 DPPH 自由基活性之间存在良好的相关性。该研究表明，包括儿茶素部分和完全共轭体系在内的独特结构使得该类化合物成为有前途的抗氧化剂。
