87099-76-1Relevant articles and documents
Effect of weakly basic conditions on the separation and purification of flavonoids and glycosides from chrysanthemum morifolium tea
Wang, Yuxiao,Xu, Zhenzhen,Wu, Yue,Li, Mo,Pang, Sicheng,Liang, Zhe,Ni, Yuanying
, (2019/01/31)
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.
Preferential alkali metal adduct formation by cis geometrical isomers of dicaffeoylquinic acids allows for efficient discrimination from their trans isomers during ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry
Makola, Mpho M.,Steenkamp, Paul. A,Dubery, Ian A.,Kabanda, Mwadham M.,Madala, Ntakadzeni E.
, p. 1011 - 1018 (2016/04/01)
Rationale Caffeoylquinic acid (CQA) derivatives are a group of structurally diverse phytochemicals that have attracted attention due to their many health benefits. The structural diversity of these molecules is due in part to the presence of regio- A nd geometrical isomerism. This structural diversity hampers the accurate annotation of these molecules in plant extracts. Mass spectrometry (MS) is successfully used to differentiate between the different regioisomers of the CQA derivatives; however, the accurate discrimination of the geometrical isomers of these molecules has proven to be an elusive task. Methods UV-irradiated methanolic solutions of diCQA were analyzed using an ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/QTOFMS) method in negative ionisation mode. An in-source collision-induced dissociation (ISCID) method was optimized by varying both the capillary and cone voltages to achieve differential fragmentation patterns between UV-generated geometrical isomers of the diCQAs during MS analyses. Results Changes in the capillary voltage did not cause a significant difference to the fragmentation patterns of the four geometrical isomers, while changes in the cone voltage resulted in significant differences in the fragmentation patterns. The results also show, for the first time, the preferential formation of alkali metal (Li+, Na+ and K+) adducts by the cis geometrical isomers of diCQAs, compared to their trans counterparts. Conclusions Optimized QTOFMS-based methods may be used to differentiate the geometrical isomers of diCQAs. Finally, additives such as metal salts to induce adduct formation can be applied as an alternative method to differentiate closely related isomers which could have been difficult to differentiate under normal MS settings.
Antioxidant constituents of almond [Prunus dulcis (Mill.) D.A. Webb] hulls
Takeoka, Gary R.,Dao, Lan T.
, p. 496 - 501 (2007/10/03)
Almond hulls (Nonpareil variety) were extracted with methanol and analyzed by reversed phase HPLC with diode array detection. The extract contained 5-O-caffeoylquinic acid (chlorogenic acid), 4-O-caffeoylquinic acid (cryptochlorogenic acid), and 3-O-caffe
