Green Pigment Formed by the Reaction of Chlorogenic Acid (or Caffeic Acid Esters) with a Primary Amino Compound during Food Processing

American Foulbrood (AFB) is a deadly bacterial disease affecting pupal and larval honey bees. AFB is caused by the endospore-forming bacterium Paenibacillus larvae (PL). Propolis, which contains a variety of organic compounds, is a product of bee foraging and is a resinous substance derived from botanical substances found primarily in trees. Several compounds from the class of caffeic acid esters, which are commonly found in propolis, have been shown to have antibacterial activity against PL. In this study, six different caffeic acid esters were synthesized, purified, spectroscopically analyzed, and tested for their activity against PL to determine the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs). Caffeic acid isopropenyl ester (CAIE), caffeic acid benzyl ester (CABE), and caffeic acid phenethyl ester (CAPE) were the most effective in inhibiting PL growth and killing PL cell with MICs and MBCs of 125 µg/mL when used individually, and a MIC and MBC of 31.25 µg/mL for each compound alone when CAIE, CABE, and CAPE are used in combination against PL. These compounds inhibited bacterial growth through a bactericidal effect, which revealed cell killing but no lysis of PL cells after 18 h. Incubation with CAIE, CABE, and CAPE at their MICs significantly increased reactive oxygen species levels and significantly changed glutathione levels within PL cells. Caffeic acid esters are potent bactericidal compounds against PL and eliminate bacterial growth through an oxidative stress mechanism.

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Synthesis and bioactivity of novel caffeic acid esters from Zuccagnia punctata

Journal of Asian Natural Products Research ◽

10.1080/10286020500246683 ◽

2006 ◽

Vol 8 (8) ◽

pp. 683-688 ◽

Cited By ~ 11

Author(s):

M. S. Ramachandra ◽

G.V. Subbaraju

Keyword(s):

Caffeic Acid ◽

Caffeic Acid Esters ◽

Acid Esters

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Feature-Based Molecular Networking to Target the Isolation of New Caffeic Acid Esters from Yacon (Smallanthus sonchifolius, Asteraceae)

Metabolites ◽

10.3390/metabo10100407 ◽

2020 ◽

Vol 10 (10) ◽

pp. 407

Author(s):

Guillermo F. Padilla-González ◽

Nicholas J. Sadgrove ◽

Gari V. Ccana-Ccapatinta ◽

Olga Leuner ◽

Eloy Fernandez-Cusimamani

Keyword(s):

Mass Spectrometry ◽

Caffeic Acid ◽

High Resolution Mass Spectrometry ◽

Chemical Diversity ◽

Bioactive Metabolites ◽

Molecular Networking ◽

Smallanthus Sonchifolius ◽

Feature Based ◽

Caffeic Acid Esters ◽

Acid Esters

Smallanthus sonchifolius (yacon) is an edible tuberous Andean shrub that has been included in the diet of indigenous people since before recorded history. The nutraceutical and medicinal properties of yacon are widely recognized, especially for the improvement of hyperglycemic disorders. However, the chemical diversity of the main bioactive series of caffeic acid esters has not been explored in detail. In this metabolomics study, we applied the latest tools to facilitate the targeted isolation of new caffeic acid esters. Using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), we analyzed extracts from different organs (roots, vascular tissues of the stems, stem epidermis, leaves, bracts, and ray flowers) and followed a feature-based molecular networking approach to characterize the structural diversity of caffeic acid esters and recognize new compounds. The analysis identified three potentially new metabolites, one of them confirmed by isolation and full spectroscopic/spectrometric assignment using nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), and MS/MS. This metabolite (5-O-caffeoyl-2,7-anhydro-d-glycero-β-d-galacto-oct-2-ulopyranosonic acid), along with eight known caffeic acid esters, was isolated from the roots and stems. Furthermore, based on detailed tandem MS analyses, we suggest that the two isomeric monocaffeoyl-2,7-anhydro-2-octulopyranosonic acids found in yacon can be reliably distinguished based on their characteristic MS2 and MS3 spectra. The outcome of the current study confirms the utility of feature-based molecular networking as a tool for targeted isolation of previously undescribed metabolites and reveals the full diversity of potentially bioactive metabolites from S. sonchifolius.

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Plant-derived phenolic compounds prevent the DNA single-strand breakage and cytotoxicity induced by tert-butylhydroperoxide via an iron-chelating mechanism

Biochemical Journal ◽

10.1042/bj3640121 ◽

2002 ◽

Vol 364 (1) ◽

pp. 121-128 ◽

Cited By ~ 70

Author(s):

Piero SESTILI ◽

Giuseppe DIAMANTINI ◽

Annalida BEDINI ◽

Liana CERIONI ◽

Ilaria TOMMASINI ◽

...

Keyword(s):

Caffeic Acid ◽

Polyphenolic Compounds ◽

Iron Chelators ◽

Protective Effects ◽

Experimental Conditions ◽

Direct Function ◽

Tert Butylhydroperoxide ◽

Caffeic Acid Esters ◽

Acid Esters

The protective effects of selected members from a series of caffeic acid esters and flavonoids were tested in various toxicity paradigms using U937 cells, previously shown to be sensitive to either iron chelators or bona fide radical scavengers or to both classes of compounds. It was found that all the protective polyphenols were active at very low concentrations and that their effects were observed only under those conditions in which iron chelators also afforded protection. Consistently, active polyphenolic compounds, unlike the inactive ones, effectively chelated iron in an in vitro system. It follows that, at least under the experimental conditions utilized in the present study, the most prominent activity of these polyphenolic compounds resides in their ability to chelate iron. Further studies revealed that the protective effects afforded by the caffeic acid esters and flavonoids were largely mediated by the catechol moiety and that the relative biological potency of these compounds was a direct function of their lipophilicity.

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One-pot preparation of caffeic acid esters from 3, 4-dihydroxybenzaldehyde

Journal of Chemical Research ◽

10.3184/030823406778521310 ◽

2006 ◽

Vol 2006 (9) ◽

pp. 586-588 ◽

Cited By ~ 12

Author(s):

Wei-Xiao Hu ◽

Chun-Nian Xia ◽

Guo-Hong Wang ◽

Wei Zhou

Keyword(s):

Caffeic Acid ◽

One Pot ◽

Caffeic Acid Esters ◽

Acid Esters

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New Caffeic Acid Esters from Plazia daphnoides

Zeitschrift für Naturforschung C ◽

10.1515/znc-2003-1-206 ◽

2003 ◽

Vol 58 (1-2) ◽

pp. 39-41 ◽

Cited By ~ 2

Author(s):

Maritza Hoeneisen ◽

Julio Alarcón ◽

Pedro Aqueveque ◽

Magalis Bittner ◽

Jose Becerra ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Caffeic Acid ◽

Caffeic Acid Esters ◽

Acid Esters

Two new 3,4 dihydroxycinnamic acid esters have been isolated from Plazia daphnoides. The structures were elucidated by NMR spectroscopy

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Metabolomic and Gene Expression Studies Reveal the Diversity, Distribution and Spatial Regulation of the Specialized Metabolism of Yacón (Smallanthus sonchifolius, Asteraceae)

International Journal of Molecular Sciences ◽

10.3390/ijms21124555 ◽

2020 ◽

Vol 21 (12) ◽

pp. 4555 ◽

Cited By ~ 1

Author(s):

Guillermo F. Padilla-González ◽

Evelyn Amrehn ◽

Maximilian Frey ◽

Javier Gómez-Zeledón ◽

Alevtina Kaa ◽

...

Keyword(s):

Gene Expression ◽

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Caffeic Acid ◽

Specialized Metabolism ◽

Smallanthus Sonchifolius ◽

Spatial Regulation ◽

Caffeic Acid Esters ◽

Acid Esters ◽

Scanning Electron

Smallanthus sonchifolius, also known as yacón, is an Andean crop species commercialized for its nutraceutical and medicinal properties. The tuberous roots of yacón accumulate a diverse array of probiotic and bioactive metabolites including fructooligosaccharides and caffeic acid esters. However, the metabolic diversity of yacón remains unexplored, including the site of biosynthesis and accumulation of key metabolite classes. We report herein a multidisciplinary approach involving metabolomics, gene expression and scanning electron microscopy, to provide a comprehensive analysis of the diversity, distribution and spatial regulation of the specialized metabolism in yacón. Our results demonstrate that different metabolic fingerprints and gene expression patterns characterize specific tissues, organs and cultivars of yacón. Manual inspection of mass spectrometry data and molecular networking allowed the tentative identification of 71 metabolites, including undescribed structural analogues of known bioactive compounds. Imaging by scanning electron microscopy revealed the presence of a new type of glandular trichome in yacón bracts, with a distinctive metabolite profile. Furthermore, the high concentration of sesquiterpene lactones in capitate glandular trichomes and the restricted presence of certain flavonoids and caffeic acid esters in underground organs and internal tissues suggests that these metabolites could be involved in protective and ecological functions. This study demonstrates that individual organs and tissues make specific contributions to the highly diverse and specialized metabolome of yacón, which is proving to be a reservoir of previously undescribed molecules of potential significance in human health.

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