Dicaffeoylquinic acid

The principal CGA isomers identified in green coffee include three caffeoylquinic acid isomers, 3-CQA [327-97-9], 4-CQA [905-99-7], and 5-CQA [906-33-2], three dicaffeoylquinic acid isomers, 3,4-diCQA [14534-61-3], 3,5-diCQA [2450-53-5], and 4,5-diCQA [57378-72-0], and three feruloylquinic acid isomers, 3-FQA [1899-29-2], 4-FQA, and 5-FQA [40242-06-6]. The total CGA level is somewhat higher in robustas compared to arabicas. The 5-CQA is the predominant isomer both in arabicas, ie, 4—5% dry basis (db), and in robustas, 5—6% db, and is known to form in vitro and possibly in vivo complexes with caffeine [58-08-2]. Greater compositional differences between robustas and arabicas are found in the minor CGA isomers, eg, 3,4-diCQA, 5-FQA,... 

Robusta coffee has a somewhat higher phenolic content than Arabica (see Table 7). The feruloylquinic and dicaffeoylquinic acid content in Robusta is higher than in Arabica coffee beans.71 72... 

An extract from Lactuca indica showed significant free radical scavenging activity, and protected phixl74 supercoiled DNA against strand cleavage and reduced oxidative stress in human promyelocytic leukemia HL-60 cells. On account of protocatechulic acid, methyl p-hydroxybenzoate, caffeic acid, 3,5-dicaffeoylquinic acid, luteolin 7-O-fT glucopyranoside, and quercetin 3-0-(3-g 1 ucopyranoside are the major antioxidative constituents (111). 

Clifford MN, Knight S, Kuhnert N. 2005. Discriminating between the six isomers of dicaffeoylquinic acid by LC-MS(n). J Agric Food Chem 53(10) 3821-3832. 

AMOUNTS OF MONOCAFFEOYLQUINIC ACIDS (MNOCQA), DICAFFEOYLQUINIC ACIDS (DICQA), AND FLAVONIDES (FLAV) IN DRIED ARTICHOKE EXTRACTS. RESULTS ARE EXPRESSED AS PER CENT (%) SD ALL SAMPLES WERE INJECTED IN TRIPLICATE... 

Gu R, Don G Wang J, Dong J, Meng Z. (2007) Simultaneous determination of 1,5-dicaffeoylquinic acid and its active metabolites in human plasma by liquid chromatography-tandem mass spectrometry for pharmacokinetic studies. J Chromatogr B 852 85-91. 

Yang B, Meng Z, Dong J, Yan L, Zou L, Tang Z, Dou G. (2005) Metabolic profile of 1,5- dicaffeoylquinic acid in rats, an in vivo and in vitro study. Drug Metab Dispos 33 930-936. 

Hellmann, J., Muller, E., and Merfort, I., Flavonoid glucosides and dicaffeoylquinic acids from flower heads of Buphthalmum salicifolium. Phytochemistry, 51, 713, 1999. 

Several studies published since March 1996 have expanded the list of in vitro integrase inhibitors effective at IC50 values below 100 pM. These include two dicaffeoylquinic acids obtained from medicinal plants and a synthetic analog, L-chicoric acid [68], the HIV protease inhibitors NSC 117027 and NSC 158393 [69], certain anthraquinone derivatives [70], coumermycin, and pyridoxal phosphate [71]. In addition to exhibiting in vitro inhibition, the dicaffeoylquinic acids effectively inhibited HIV-1 replication in T-lymphoblastoid cell lines [68]. 

There is no doubt that caffeic acid is the cinnamate that occurs most extensively, and the various caffeoylquinic acids (CQA) and dicaffeoylquinic acids (diCQA) are the most ubiquitous conjugates. Usually the 5-isomers dominates, but in some fruit and brassicas the 3-isomer is prevalent. Because of the quantity commonly consumed, coffee... 

Kojima, M., and Kondo, T., 1985, An enzyme in sweet potato root which catalyzes the conversion of chlorogenic acid, 3-caffeoylquinic acid, to isochlorogenic acid, 3,5-dicaffeoylquinic acid, Agric. Biol. Chem. 49 2467-2469. 

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]. 

The red-leaved lettuce Lollo Rosso contains the hydroxycinammates caf-feoyltartaric acid, dicaffeoyltartaric acid, 5-O-caffeoylquinic acid, and 3,5-0-dicaffeoylquinic acid (Fig. 1.31) [Ferreres et al., 1997]. 5-O-Caffeoylquinic acid has also been detected in tomatoes [Paganga et al., 1999]. 

Green coffee beans (Coffea arabica) are one of the richest dietary sources of chlorogenic acids. 5-O-Caffeoylquinic acid is the dominant chlorogenic acid accounting for 50% of the total. This is followed by 3-0- and 4-O-caffeoyl-quinic acid, the three analogous feruloylquinic acids and 3,4-0-, 3,5-0- and 4,5-O-dicaffeoylquinic acids (Fig. 1.32) [Clifford, 1999]. Levels decline ca. 80% during the roasting of coffee beans, but sizable amounts with substantial antioxidant activity are still found in the typical cup of coffee. 

O-Dicaffeoylquinic acid Figure 1.32 Main chlorogenic acids in green coffee beans. 

Chlorogenic acid has been used as a name for 5-O-caffeoylquinic acid by the authors of the reports cited except [Monteiro et al., 2007], 3-, 4-, or 5-CQA, 3-, 4-or 5-O-caffeoylquinic acid BA, benzoic acid CA, caffeic acid CLA, chlorogenic acid or 5-O-caffeoylquinic acid dHCA, dihydrocaffeic acid diCQA, dicaffeoylquinic acid FA, ferulic acid FQA, feruloylquinic acid GA, gallic acid HA, hippuric isoFA, isoferulic acid m-CA, ra-coumaric acid ra-HPPA, m-hydroxyphenylpropionic acid p-CA, p-coumaric acid p-HBA, p-hydroxybenzoic acid PPA, phenylpropionic acid. 

Robinson, W., Cordeiro, M., Abdel-Malek, S., Jia, Q., Chow, S., Reinecke, M., and Mitchell, W. 1996b. Dicaffeoylquinic acid inhibitors of human immunodeficiency virus integrase inhibition of the core catalytic domain of human immunodeficiency virus integrase. Mol. Pharmacol. 50, 846-855. 

Parejo et al. (2004) identified caffeoyl-quinic acids, dicaffeoylquinic acids, flavonoids and rosmarinic acid among ten main antioxidant phenolic compounds from bitter fennel, F. vulgare, using a simple high-performance liquid chromatography (HPLC). Distilled fennel was found to contain a higher proportion of antioxidant phenolic compounds than non-distilled plant material. 

The above-mentioned hypothesis (see Section 4.2.1.4) that 4-coumaroylshikimate is hydroxylated to caffeoylshikimate and then the caffeoyl moiety is re-transferred to coenzyme A by the same acyltransferase is an example for caffeoylshikimate as a caffeoyl donor. As already indicated before, this is also true for the formation of caffeoylglucarate and -galactarate in tomato (Strack et al, 1987b Strack and Gross, 1990). Also dicaffeoylquinic acids can be formed by caffeoyl transfer from chlorogenic acid to another chlorogenic acid molecule in sweet potato (Kojima and Kondo, 1985 Villegas et al, 1987). 

Lactacystin, salinosporamide A, epoxomicin, dihydroeponemycin, EGCG,3,5-dicaffeoylquinic acid, apigenin, quercetin, celastrol, withaferin A... 

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