Tea brewed from chrysanthemum flowers has been widely used in Chinese medicine. The possibly medicinal compounds in Chrysanthemum morifolium tea can be purified by preparative high performance liquid chromatography (HPLC), but this is usually done with acidic conditions, which leads to the hydrolysis of glycosides. In hopes of avoiding this hydrolysis, we explored the effect of weakly basic conditions on the separation and purification of flavonoids and glycosides from Chrysanthemum morifolium. We also explored the effects of weakly basic conditions on chlorogenic acid (3-CQA) and apigenin-7-O-glucoside (A7G). Our results show that the concentration of the weakly basic ammonium hydrogen carbonate and time had no significant effect on A7G, p < 0.01, but it had a significant effect on 3-CQA, p < 0.01. HPLC and ultraviolet (UV) analysis showed that the structure of 3-CQA is destroyed in weakly basic conditions. Caffeic acid, quinic acid, and 3,4-dihydroxymandelic acid, which is a hydrolysate of 3-CQA, were identified by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The results showed that weakly basic conditions could be used for the purification of flavonoids and glycosides but not for caffeoylquinic acids. Moreover, our work clarified the hydrolysis behaviour of caffeoylquinic acids, which can be helpful for research into their functional aspects.
菊花茶被广泛应用于中药。菊花茶中可能含有的药用化合物可以通过制备性高效
液相色谱(HPLC)进行纯化,但通常在酸性条件下进行,这会导致糖苷的
水解。为了避免这种
水解,我们探讨了弱碱性条件对从菊花茶中分离和纯化
黄酮类化合物和糖苷的影响。我们还探讨了弱碱性条件对
绿原酸(3-
CQA)和
芹菜素-7-O-
葡萄糖苷(A7G)的影响。我们的结果显示,弱碱性氢
碳酸铵的浓度和时间对A7G没有显著影响,p <0.01,但对3-CQA有显著影响,p <0.01。HPLC和紫外(UV)分析显示,在弱碱性条件下,3-CQA的结构被破坏。通过超高效液相色谱四极杆飞行时间质谱(UPLC-Q-TOF-MS)鉴定了咖啡酸、奎宁酸和3,4-二羟基苯乙酸,这是3-CQA的水解产物。结果表明,弱碱性条件可用于黄酮类化合物和糖苷的纯化,但不适用于烟酰奎宁酸。此外,我们的研究阐明了烟酰奎宁酸的
水解行为,这对研究其功能方面可能有所帮助。