4- <9-Coumaroylquinic acid

Several studies reflect the widespread use of the LC-MSn for the characterization of phenolic acids, predominantly chlorogenic acids (Clifford and others 2003, 2005, 2006a,b,c). For example, using LC-MS3 it is possible to discriminate between different isomers of coumaroylquinic acid, caffeoylquinic acid, and feruloylquinic acid. In addition, a hierarchical key was proposed to facilitate the process of identification when standards are not available (Clifford and others 2003). 

Fig. 2.49. Profile of Hypericum perforatum extract with the H LC-MS attributions of the components detected. 1 = chlorogenic acid isomer 2 = 3-0- -coumaroylquinic acid 3 = chlorogenic acid 4 = rutin 5 = hyperoside 6 = isoquercitrin 7 = 3,3, , , 7-pentahydroxyflavanone 7-0-rhamnopyranoside 8 = quercitrin 9 = quercetin 10 = 13,118 tapigenin 11 = pSeudohypericin 12 = hypericin 13 = hyperforin analogue 14 = hyperform dialogue 15 = hyperforin 16 = adhyperforin. Reprinted with permission from M. Brolis eta. [ ].

Campanula glomerata L. f. canescens (Maxim.) Kitag. C. glomerata L. var. dahurica Fisch. ex Ker-Gawl. C. punctata Lam. Feng Lin Cao (whole plant) Quercetin, isorhamnetin, kaempferol, hyperoside, isoquercetin, trifolin, chlorogenic acid, methyl caffeate, coumaroylquinic acid.48 For throat infection, headache... 

Coumaroylquinic acid Coumesterol Crataegol acid Crataegolic acid... 

For phenolics in fruit by-products such as apple seed, peel, cortex, and pomace, an HPLC method was also utilized. Apple waste is considered a potential source of specialty chemicals (58,62), and its quantitative polyphenol profile may be useful in apple cultivars for classification and identification. Chlorogenic acid and coumaroylquinic acids and phloridzin are known to be major phenolics in apple juice (53). However, in contrast to apple polyphenolics, HPLC with a 70% aqueous acetone extract of apple seeds showed that phloridzin alone accounts for ca. 75% of the total apple seed polyphenolics (62). Besides phloridzin, 13 other phenolics were identified by gradient HPLC/PDA on LiChrospher 100 RP-18 from apple seed (62). The HPLC technique was also able to provide polyphenol profiles in the peel and cortex of the apple to be used to characterize apple cultivars by multivariate statistical techniques (63). Phenolic compounds in the epidermis zone, parenchyma zone, core zone, and seeds of French cider apple varieties are also determined by HPLC (56). Three successive solvent extractions (hexane, methanol, aqueous acetone), binary HPLC gradient using (a) aqueous acetic acid, 2.5%, v/v, and (b) acetonitrile fol-... 

Fig. 17 HPLC separation of chlorogenic acids from roasted coffee. (From Ref. 143.) 1-15 = hydroxy-cinnamic acids 7, 8 = coumaroylquinic acids 16 = caffeoyltryptophan.

Carrots (Duacus carota) contain a range of chlorogenic acids including 3-0-and 5-O-caffeoylquinic acids, 3-0-p-coumaroylquinic acid, 5-O-feruloylquinic acid, and 3,5-O-dicaffeoylquinic acids (Fig. 1.30). These chlorogenic acids are found in almost all varieties of carrot with a 10-fold higher level of 5-O-caffeoylquinic acid in purple carrots [Alasalvar et al., 2001]. 

Phenolic and furfural compounds in apple juice were determined by HPLC using a combination of ELD and DA-UVD. LOD for ELD were 4 to 500 times greater than those for spectrophotometric detection. The content of phenolics varied from 30 to 115 mgL, including major phenolic components such as chlorogenic acid (95), p-coumaroylquinic acid (98) and phloridzin (96) and minor ones such as caffeic acid (25), p-coumaric acid (26), ferulic acid (69), gallic acid (8), protocatechuic acid (27) and catechin (3) . The same methods were also applied for the analysis of maple products. The phenolic content was dependent on the source of the product. Application of reverse osmosis to maple sap caused a relative decrease of aldehydes and alcohols and an increase of phenolic acids. 

Cyclohexanecarboxylic acid, 1,3,4-trihydroxy-5-[[3-(4-hydroxyphenyl)-1-oxo-2-propenyl]oxy]-, [1S-(1a,3a,4a,5p)]- p-coumaroylquinic acid ... 

Eleven chlorogenic acids (e.g., p-coumaroylquinic acids, caffeoylquinlc acids, feruloylquinic acids) were extracted fiom coffee and analyzed on a Cjg column... 

Sweet cherry 75-339 Cyanidin 5-0-rutinoside, 3-p-coumaroylquinic acid... 

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