Identification and Quantification of Caffeic and Rosmarinic Acid in Complex Plant Extracts by the Use of Variable-Temperature Two-Dimensional Nuclear Magnetic Resonance Spectroscopy

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• 作者：Vassiliki Exarchou ; Anastasios Troganis ; Ioannis P. Gerothanassis ; Maria Tsimidou ; and Dimitrios Boskou
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2001
• 出版时间：January 2001
• 年：2001
• 卷：49
• 期：1
• 页码：2 - 8
• 全文大小：124K
• 年卷期：v.49,no.1(January 2001)
• ISSN：1520-5118

文摘

A combination of advanced nuclear magnetic resonance (NMR) methodologies for the analysis ofcomplex phenolic mixtures that occur in natural products is described, with particular emphasis oncaffeic acid and its ester derivative, rosmarinic acid. The combination of variable-temperature two-dimensional proton-proton double quantum filter correlation spectroscopy (¹H-¹H DQF COSY)and proton-carbon heteronuclear multiple quantum coherence (¹H-¹³C HMQC) gradient NMRspectroscopy allows the identification and tentative quantification of caffeic and rosmarinic acidsat 243 K in extracts from plants of the Lamiaceae family, without resorting to previouschromatographic separation of the components. The use of proton-carbon heteronuclear multiplebond correlation (¹H-¹³C HMBC) gradient NMR spectroscopy leads to the complete assignment ofthe correlations of the spins of H_2a and H_3a with the ester and carboxyl carbons of rosmarinic andcaffeic acid, even at room temperature, and confirms the results of the above methodology.Quantitative results are in reasonable agreement with reverse phase HPLC measurements.Keywords: Antioxidants; Lamiaceae plants; caffeic acid; rosmarinic acid; DQF-COSY; HMQC;HMBC; NMR spectroscopy; RP-HPLC